System of exercises in the gym for weight loss

 Toning up and losing weight are not quite the same. Weight reduction is clear-cut as it only includes lowering your body weight, which can be done by dieting alone. Toning yet is a different matter. For a toned physique, you need tight, defined muscles, which means

hitting the gym

for some resistance training. Cardio may be the way many choose to lose weight, but making weight training a mainstay in your gym routine can complement your cardio routine and will lead to faster results both in terms of weight loss and toning. So, let’s talk about gym exercises for weight loss and toning up.

How often you should do gym exercises for weight loss

Determine how many days you’ll be able to get to the gym each week. Ideally you want at least three days and a maximum of six. Dedicate three weekly sessions to weight training. Make these total-body gym exercises for toning and weight loss, in which you work every major muscle group within a session. This burns off more calories and fat than training only one or two muscle groups each work out, composes trainer Nate Green in “Built for Show.” Leave at least one day between each weights work out. If you’re able to get to the gym six times weekly, perform weights and cardio on different days; if not, then do both in each work out.

Try multi-joint gym exercises

Easy gym exercises for weight loss

The best way of weight training would be to select multi-joint gym exercises for weight loss that reach tons of distinct muscle groups, notes trainer Jacqueline Silvestri Banks on the Fox News website. Moves such as squats, lunges, deadlifts, pushups and rows should constitute the bulk of your plan. Perform two lower-body and three or four upper-body exercises each session, each for three to four sets of six to 10 repetitions. This goes against the conventional recommendation of using light weights for higher repetitions for toning, but lifting heavier supplies a greater anabolic response, which really results in quicker fat burning, notes Banks.

Interval training is the best

For weight reduction and toning cardio, you can’t beat interval training. Increasing your cardio intensity by doing intervals not only saves you time, but also means you keep burning fat long after you finish your session, says strength coach Jeremy DuVall on the “Mens Fitness” website. Interval training involves switching between all out bursts of maximum effort and somewhat more, somewhat simpler bouts of cardio. After a warmup, work at maximum strength for 10 seconds, then ease back into a constant rate for one minute and 20 seconds. Duplicate this protocol for 20 minutes. The best thing about interval gym exercises for losing weight is you could use any gymnasium cardio machine, or try something a bit different such as sprinting exterior.

The remaining factors

Diet is crucial too – you will not lose weight and tone up unless you also reduce your food consumption. Get rid of the junk food from your diet, focus on unprocessed foods that keep you feeling full, such as vegetables and fruits, lean meats, dairy and whole grains. Plan to lose 1 to 2 pounds per week; you will should cut 3,500 calories to lose 1 pound of fat. Reducing your daily calorie intake by 500 will give a 1-pound decrease each week; adding exercise should take you nearer to the 2-pounds each week mark. If you reach a weight reduction plateau, add 10 to 40 minutes of moderate-intensity cardio after each interval workout.

weightlosster.com

Physical activity is a natural part of being human, and exercise is an essential part of a healthy lifestyle.

And as everyone involved in fitness knows, training is also an invaluable tool for shaping and sculpting the body. Progressive resistance training is especially effective when it comes to body recomposition, as it increases lean mass and helps you build a muscular frame and good-looking physique.

But what about those folks who want to shed fat? Is it effective to exercise to lose weight? Conventional wisdom says yes, and on a superficial level it makes sense that expending more energy can help you get into the pants you’ve been keeping around since your lean days.

Does Exercise for Weight Loss Hold up in the Real World?

The idea that exercise “burns off the fat” is so ingrained in most people’s belief system that we just accept it as true, and selling gym memberships and personal training on the idea that the best way is to exercise to lose weight has become a simple task.

Also, since it’s easy to find an isolated study that seems to show significant exercise-induced weight loss, the average gym goer rarely questions the link between exercise and weight loss. If the actual workout results don’t stack up to the preconceived notions — as they often don’t in terms of exercise for weight loss — the conclusion is that it’s something wrong with the training program or the general effort in the gym, not with the underlying premise of the training.

However, physical activity hasn’t always been synonymous with weight loss. It wasn’t until the 1960s that researchers, such as the French-American nutritionist Jean Mayer, really began extolling the virtues of exercise in the treatment of overweight and obesity.

Despite the many limitations and weaknesses of the early studies on exercise and fat loss, the idea that expending more energy helps you shed the pounds was so easy to believe that the mantra “eat less, move more” started to gain foothold as weight loss advice 101.

Physical Activity Levels Throughout History

In evolutionary terms clearly the average human energy expenditure has declined dramatically. It’s no doubt that the majority of people living in the world today would benefit from being more active, but we can’t extrapolate the mismatch between energy expenditure in the lean Paleolithic man and energy expenditure in the overweight modern human to mean that exercise is the way to go for leanness.

Also, the fact that several non-westernized cultures, such as the Kitavans on the Island of Kitava and the Hadza of Northern Tanzania, are lean and healthy even though they aren’t especially active suggests that we don’t necessarily have to exercise to be lean (1).

Furthermore, while it’s often believed that we are less active today than in any other part of human evolution, statistics show that physical activity expenditure has not declined over the same period that obesity rates have increased dramatically (2). Although this doesn’t tell us that much about the connection between exercise and weight loss, it does make it clear that inactivity, at least in itself, is not the primary cause of the obesity epidemic.

Does Pouring More Energy Out of the System Transfer Into Fat Loss?

Weight training promotes muscle growth and strength development as an adaptive response to exercise, and it’s sometimes assumed that fat loss is an adaptive response to aerobic exercise since a leaner body could lead to better performance in aerobic activities. When talking about exercise-induced energy expenditure, I’m not just talking about energy output during training, but also the elevated energy expenditure that occurs in the hours (and days) after a workout.

Everyone with a basic understanding of thermodynamics agrees that creating an imbalanced energy equation is necessary to either gain or lose weight, which means that you either have to increase energy expenditure, decrease energy intake, or both if you want to get rid of the excess belly fat. Since we know that the human body isn’t a passive vehicle that simply comes along for the ride, this doesn’t necessarily mean that telling people to move more is good weight loss advice.

Of course, if you restrict your caloric intake to a specific amount of calories each day (as dieting bodybuilders and folks on low-calorie diets do), increasing your energy expenditure through exercise will naturally help you lose more fat. However, that isn’t what we’re talking about here. Someone who’s already very lean and want to shed more fat (e.g., down to single digits of body fat for male), generally has to consciously restrict calories to lose weight.

Conscious calorie restriction can also play a role for those who are overweight and obese, but studies show that simply going on a calorie restricted diet is rarely effective in the long-term.  This is because you’re fighting your body’s hard-wired mechanisms for regulating fat storage.

Yes, energy expenditure has to increase and/or energy intake has to decrease if you want to lose weight, but this should happen naturally as a result of the diet you’re eating and your lifestyle, not by chronically starving yourself.

So I’m not discussing the 200-pound fitness competitor who goes on a calorie restricted diet to get ready for the stage. Naturally, this guy will shed more fat if he expends more energy through exercising, while at the same time keeps his energy intake the same.

I’m talking about those folks who are interested in long-term weight loss and aren’t going to starve themselves forever. Because this is where the important question lies: Can we simply pour more energy out of the system (our body) to lose weight, or will the system kick-start mechanisms that make us compensate for the increased energy output to maintain what it considers to be an equilibrium?

Controlling for Confounding Variables

What happens when people start working out? They generally get more interested in health and nutrition and often change their diet, sleeping patterns, etc. This isn’t a universal behaviour, but it’s a very common one. Most of us have probably heard about that guy who lost a lot of weight when he started exercising, but was it really the exercise in itself that triggered the weight loss? Perhaps he made other lifestyle changes that affected fat regulation, or perhaps this person simply was one of those people who respond great to exercise.

However, some folks also respond in the opposite way in the sense that they reward themselves for the efforts in the gym by eating more crap (most people tend to overestimate the amount of calories burned during exercise) and being less active during the rest of the day. The fact is that we can’t really draw any universal conclusions from these types of anecdotal reports.

These types of confounding variables are one of the primary reasons why it’s so hard to carry out well-controlled studies on exercise for weight loss. Unless it’s a metabolic ward study, participants are typically given a training program to follow for a certain number of weeks and then sent home.

Even though participants are supervised along the way, it’s very difficult to control for various lifestyle factors that can affect the results. That’s why it’s generally easier to do a study where subjects are instructed to exercise while at the same time eat a calorie restricted diet.

However, the problem with these studies is that they don’t really tell us much about the effectiveness of exercise on its own. Naturally, a higher energy expenditure will help boost fat loss if you eat a calorie restricted diet, because we’re eliminating compensatory mechanisms as increased food intake.

What Does the Science Really Say About Exercise for Weight Loss?

There are hundreds of studies investigating the effects of exercise for weight loss, so let’s narrow the scope by looking at comprehensive reviews, meta-analyses, and high-quality randomized-controlled trials.

Meta-analyses are often considered the strongest possible evidence since they combine results from several different studies, and there’s no doubt that high quality meta-analyses and systematic reviews provide invaluable information.

However, it’s important to note that these types of statistical analyses also have their limitations. it’s important that you figure out how to quickly analyze fitness research. They can only be as good as the studies they are based on, and one problem with “lumping” several trials together is that the strength and weaknesses of each study sometimes get lost. However, meta-analyses and systematic reviews provide a good overview of the current data (Skip this list if you’re not interested in the hard facts).

Let’s begin by looking at some of the data from the 1980s and 1990s. In 1997, a meta-analysis of the past 25 years of weight loss research found that a 15-week diet or diet plus exercise program resulted in the same weight loss after 15 weeks (11 kg) (3).

While total weight loss was the same, diet plus exercise intervention resulted in a slightly higher fat loss. Weight loss due to exercise alone was 2.9 kg. This meta-analysis focused on the obese population. Two other meta-analysis (4,5) found that weight loss through exercise alone is lower (1-2 kg) in non-obese subjects.

A recent systematic review and meta-analysis looked at the randomized controlled trials done on isolated aerobic exercise (no dietary intervention) and weight loss. The review composed of 14 trials involving 1847 overweight or obese patients shows that isolated aerobic exercise only results in an average weight loss of 1.6 kg after six months, and an additional 6 months of training didn’t result in any additional weight reduction (6).

“Evidence indicates that even when the exercise is supervised and closely monitored, there’s variability in weight change, both in the direction and magnitude” (7). While some people find that exercise on its own is somewhat effective for weight loss, others actually gain weight because they end up compensating by eating more food.

One of the most recent reviews (2014) on the role of exercise and physical activity in weight loss and maintenance concludes the following: “Based on the present literature, unless the overall volume of aerobic ET is very high, clinically significant weight loss is unlikely to occur. Also, ET also has an important role in weight regain after initial weight loss.

Overall, aerobic ET programs consistent with public health recommendations may promote up to modest weight loss (~2 kg), however the weight loss on an individual level is highly heterogeneous. Clinicians should educate their patients on reasonable expectations of weight loss based on their physical activity program and emphasize that numerous health benefits occur from PA programs in the absence of weight loss (8) .”

Another recent review (2013) had the following to say about high-intensity exercise versus moderate-intensity exercise for weight loss: “… in the literature on overweight or obese people, there is little conclusive evidence for more favorable effects with high-intensity training than with continuous moderate-intensity exercise on body weight or fat mass loss (9).”

Since the purpose of resistance exercise usually isn’t to lose weight, it’s no surprise that aerobic exercise seems to be more effective for visceral fat loss (10). While isolated resistance training like weight lifting isn’t associated with any significant reduction in fat mass, an increase in muscle mass may lead to better metabolic control and increased basal metabolic rate, and resistance exercise is therefore often recommended in the prevention and management of obesity, type 2 diabetes, and other metabolic disorders.

Clearly if we look at the evidence as a whole, neither aerobic nor anaerobic exercise is very effective for fat loss (for the vast majority of people). This goes for both HIIT and regular cardio training. However, both aerobic and anaerobic exercise have a positive effect on insulin resistance, appetite control, blood pressure, etc. Some studies also show that some people respond to exercise by losing a “significant” amount of weight (11, 12).

Although these mixed results to a degree stem from a true individual variability, I personally believe that confounding variables, such as sleep and diet, can help explain some of the difference between participants in these studies. Regardless of how well researchers try to control for these variables, it’s very difficult to stay on top of these things when participants aren’t confined to a controlled environment.

These results seem to go against what most people believe in when it comes to exercise and weight loss. While research does support the idea that some people lose quite a bit of fat from exercising more, the average fat loss is modest at best. So, what is going on here? Why doesn’t the elevated energy expenditure both during and after exercise transfer into fat loss?

The Body’s Compensatory Responses to Exercise for Weight Loss

It’s long been known that the amount of body fat we carry is homeostatically regulated (13-16). If food intake goes down and/or exercise-induced energy expenditure goes up, the hypothalamus triggers processes (e.g., interest in food, decreased body heat production) to restore energy reserves. Obesity researchers often refer to this “defended” level of body fat as the fat mass set point (more like a range).

So while few people will argue against the fact that we have to decrease energy intake and/or decrease energy expenditure to lose weight, we also have to take into account that the body has its own mechanisms for regulating fat storage.

Like so many dieters have experienced, if we exercise more and restrict calories in an attempt to lose weight, energy expenditure per unit lean mass declines and we will be hungry and tired.

Compensatory mechanisms to exercise, such as increased food intake and/or less activity during the rest of the day, are the primary reason why the energy you burn off during exercise doesn’t necessarily transfer into permanent weight loss.

Exercise, Metabolic Health, and Food Reward

To really be able to lose weight, we have to understand how to work with our body and design a fat loss plan that helps us take control of the homeostatic system that controls fat storage on a long-term basis. This means that we have to address the causes of overeating, poor leptin sensitivity, and elevated fat mass set point.

Environmental inputs and lifestyle have a significant effect on these processes, and diet is by far the most important factor. But what about exercise? The general belief that exercise could make you lose weight because it increases energy expenditure doesn’t necessarily hold up very well since body fat levels are regulated by the brain.

However, exercise has also been shown to decrease inflammation and improve metabolic health — most notably leptin and insulin sensitivity — and these benefits probably explain why some people find that exercise is effective for weight loss.

Furthermore, exercise has a significant effect on food reward regions in the brain, but the effects seem to be highly individual, with some people experiencing an increased interest in food following exercise, while others display a reduced responsiveness to food cues (17).

As the brain is the control center for regulating energy expenditure and energy intake, these varying effects on the food-reward network could largely explain why some people respond to exercise by eating more, while others eat less. If it was just about the calories, one would expect everyone to lose the same amount of fat from exercise, given the same level of exercise-induced energy expenditure.

Wrap Up

I find that the science on exercise for weight loss is fairly consistent with my own experiences as a personal trainer. Since the idea that exercise leads to weight loss is so ingrained in most people’s belief system, many gym goers who hire a personal trainer simply think they’ll lose weight if they start exercising more. Getting clients to understand that increasing their activity levels generally doesn’t lead to much in terms of fat loss can therefore be a difficult task.

Believe me, I wish exercise was very effective for weight loss, as it would’ve made my job as a trainer/coach a lot easier. However, I acknowledge that although exercise comes with a wide spectrum of benefits, the evidence as a whole doesn’t show that it helps you lose a lot of weight.

Does this mean that exercise is a waste of time for people who are overweight and obese? No. Regular physical is an essential part of a healthy lifestyle, and there’s no doubt that the modern sedentary lifestyle is one of the primary causes of the so-called diseases of civilization. Also, while exercise isn’t the number one priority when it comes to losing weight, regular physical activity seems to be important in the prevention of obesity, insulin resistance, and the metabolic syndrome. It’s also important to remember that regular exercise allows you to eat more food without gaining fat, and for those foodies out there, this could be a win in itself.

In conclusion, the scientific literature as a whole shows that isolated (no dietary intervention) exercise for weight loss usually isn’t very effective. This suggests that most people compensate for the exercise-induced energy expenditure by eating more and/or being less active during the rest of the day.

However, a minority find that exercise on its own is very effective for weight loss, and this probably has to do with the effects on metabolic health and food-reward systems in the brain. Don’t exercise to lose weight but instead to build a strong, fit, and healthy body.

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Further Reading

Help! My Clients Won’t Follow Nutrition Advice – Jonathan Goodman

47 Random Personal Trainer Tips – Jonathan Goodman

How Much Should You Charge for Personal Training? – Brett Jarman

References

  1. http://www.staffanlindeberg.com/TheKitavaStudy.html.
  2. Westerterp KR, Speakman JR. Physical activity energy expenditure has not declined since the 1980s and matches energy expenditures of wild mammals. International journal of obesity (2005). 2008;32(8):1256-63.
  3. Miller WC, Koceja DM, Hamilton EJ. A meta-analysis of the past 25 years of weight loss research using diet, exercise or diet plus exercise intervention. International journal of obesity and related metabolic disorders : journal of the International Association for the Study of Obesity. 1997;21(10):941-7.
  4. Epstein LH, Wing RR. Aerobic exercise and weight. Addictive behaviors. 1980;5(4):371-88.
  5. Ballor DL, Keesey RE. A meta-analysis of the factors affecting exercise-induced changes in body mass, fat mass and fat-free mass in males and females. International journal of obesity. 1991;15(11):717-26.
  6. Thorogood A, Mottillo S, Shimony A, Filion KB, Joseph L, Genest J, et al. Isolated aerobic exercise and weight loss: a systematic review and meta-analysis of randomized controlled trials. The American journal of medicine. 2011;124(8):747-55.
  7. King NA, Horner K, Hills AP, Byrne NM, Wood RE, Bryant E, et al. Exercise, appetite and weight management: understanding the compensatory responses in eating behaviour and how they contribute to variability in exercise-induced weight loss. British journal of sports medicine. 2012;46(5):315-22.
  8. Swift DL, Johannsen NM, Lavie CJ, Earnest CP, Church TS. The role of exercise and physical activity in weight loss and maintenance. Progress in cardiovascular diseases. 2014;56(4):441-7.
  9. De Feo P. Is high-intensity exercise better than moderate-intensity exercise for weight loss? Nutrition, metabolism, and cardiovascular diseases : NMCD. 2013;23(11):1037-42.
  10. Slentz CA, Bateman LA, Willis LH, Shields AT, Tanner CJ, Piner LW, et al. Effects of aerobic vs. resistance training on visceral and liver fat stores, liver enzymes, and insulin resistance by HOMA in overweight adults from STRRIDE AT/RT. American journal of physiology Endocrinology and metabolism. 2011;301(5):E1033-9.
  11. King NA, Caudwell PP, Hopkins M, Stubbs JR, Naslund E, Blundell JE. Dual-process action of exercise on appetite control: increase in orexigenic drive but improvement in meal-induced satiety. The American journal of clinical nutrition. 2009;90(4):921-7.
  12. Donnelly JE, Honas JJ, Smith BK, Mayo MS, Gibson CA, Sullivan DK, et al. Aerobic exercise alone results in clinically significant weight loss for men and women: midwest exercise trial 2. Obesity (Silver Spring, Md). 2013;21(3):E219-28.
  13. Guyenet SJ, Schwartz MW. Clinical review: Regulation of food intake, energy balance, and body fat mass: implications for the pathogenesis and treatment of obesity. The Journal of clinical endocrinology and metabolism. 2012;97(3):745-55.
  14. Myers MG, Cowley MA, Munzberg H. Mechanisms of leptin action and leptin resistance. Annual review of physiology. 2008;70:537-56.
  15. Lutter M, Nestler EJ. Homeostatic and hedonic signals interact in the regulation of food intake. The Journal of nutrition. 2009;139(3):629-32.
  16. Friedman JM. A tale of two hormones. Nature medicine. 2010;16(10):1100-6.
  17. http://well.blogs.nytimes.com/2012/04/16/does-exercise-make-you-overeat/.

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Exercise!

Would you take a magic pill that could allow you to eat more, ease stress, and boost your brainpower? There is something that can do all that, and more: exercise.

Following are some fitness facts that will help you get started.

1. Exercise Boosts Brainpower

Numerous studies have shown exercise can boost memory and concentration. It increases serotonin, a neurotransmitter, in the brain that can lead to improved focus and clarity. Other studies have shown that physical activity may reduce cognitive decline in older adults.

2. Movement Melts Away Stress

Exercise reduces stress, and can help ward off depression and anxiety. Regular exercise can reduce stress hormones such as cortisol and adrenaline.

3. Exercise Gives You Energy

Studies have shown people who exercise as little as 20 minutes per day, three days a week, have less fatigue and more energy overall. Exercise increases blood flow, which allows oxygen and nutrients to reach the cells, giving you energy for daily tasks.

4. It’s Not That Hard to Find Time for Fitness

It’s not necessary to spend an hour or more at the gym to get in your daily exercise. Short bursts of activity can be incorporated throughout the day. Take a walk on your lunch break, ride bikes with your kids, do jumping jacks for 10 minutes, or run up and down the stairs for five. Getting exercise in short chunks is just as effective as doing it all at once. A cumulative half-hour per day is all that is needed for health benefits, and a total of 60 minutes per day can help you lose weight and keep it off.

5. Fitness Can Help Build Relationships

Exercising can also help strengthen relationships. Spend time with your partner or friends walking or meeting for a tennis match, instead of going out to eat. Having support also helps you keep your fitness goals.

6. Exercise Helps Ward Off Disease

Exercise can also help prevent or slow the process of a number of diseases and health conditions, including:

  • heart disease
  • stroke
  • high blood pressure
  • high cholesterol
  • type 2 diabetes
  • arthritis
  • osteoporosis (bone loss)
  • loss of muscle mass

7. Fitness Pumps Up Your Heart

Exercise makes the heart and cardiovascular system stronger. Your heart will become more efficient, pumping more blood per beat so at rest your heart rate will be lower. Even a few days after beginning exercise the body starts to adapt, and breathing is easier, your body feels less fatigue, and pain and soreness will diminish.

8. Exercise Lets You Eat More

We’ve all heard muscle burns more calories than fat, so by having more muscle your resting metabolic rate will be higher. That means you can take in more calories and still maintain your weight. It’s not a carte blanche to eat whatever you want, but you can enjoy your favorite sweets and chips in moderation when you exercise regularly.

9. Exercise Boosts Performance

Exercise will improve your performance in your athletic endeavors. Once you’ve been exercising regularly for several weeks your body will be more efficient and you will have more endurance. Your muscles will be stronger and more flexible, and your overall performance will be enhanced.

10. Weight Loss Is Not the Most Important Goal

Don’t make weight loss your only goal when you start exercising. Certainly, exercise is a helpful component of a weight loss program but the health benefits of exercise – whether you lose weight or not – are important too. Whether the number on the scale goes down or not, remember your body is still reaping the benefits of exercise. You will be sharper mentally, less stressed, and more fit overall.

Top 10 Fitness Facts

Exercise can help improve your health, your mind, your body, and your relationships. Hopefully these 10 fitness facts will inspire you to incorporate exercise into your daily routine!

Sources:

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REFERENCES:

  • Anxieity and Depression Association of America (ADAA): “Physical Activity Reduces Stress.”
  • Centers for Disease Control and Prevention (CDC): “How Much Physical Activity Do You Need?”
  • UpToDate: “The Benefits and Risks of Exercise.”

© 2005-2017 WebMD, LLC. All rights reserved.

www.onhealth.com

Physical exercise is any bodily activity that enhances or maintains physical fitness and overall health and wellness. It is performed for various reasons, including increasing growth and development, preventing aging, strengthening muscles and the cardiovascular system, honing athletic skills, weight loss or maintenance, and also enjoyment. Frequent and regular physical exercise boosts the immune system and helps prevent certain “diseases of affluence” such as coronary heart disease,type 2 diabetes, and obesity. It may also help prevent stress and depression, increase quality of sleep and act as a non-pharmaceutical sleep aid to treat diseases such as insomnia, help promote or maintain positive self-esteem, improve mental health, maintain steady digestion and treat constipation and gas, regulate fertility health, and augment an individual’s sex appeal or body image.Childhood obesity is a growing global concern, and physical exercise may help decrease some of the effects of childhood and adult obesity. Some care-providers call exercise the “miracle” or “wonder” drug—alluding to the wide variety of benefits that it can provide for many individuals. Aside from the health advantages, these benefits may include different social rewards for staying active while enjoying the environment of one’s culture. Many individuals choose to exercise publicly outdoors where they can congregate in groups, socialize, and appreciate life.

In the United Kingdom two to four hours of light activity are recommended during working hours. This includes walking and standing. In the United States, a 1995 CDC/ACSM consensus statement and a Surgeon General’s 1996 report state that every adult should participate in moderate exercise, such as walking, swimming, and household tasks, for a minimum of 30 minutes daily.

Classification

An astronaut,

Daniel Tani

, working out with a short bar to increase his upper body strength while in a

microgravity

environment

Physical exercises are generally grouped into three types, depending on the overall effect they have on the human body:

  • Aerobic exercise is any physical activity that uses large muscle groups and causes the body to use more oxygen than it would while resting. The goal of aerobic exercise is to increase cardiovascular endurance. Examples of aerobic exercise include running, cycling, swimming, brisk walking, skipping rope, rowing, hiking, playing tennis, continuous training, and long slow distance training.
  • Anaerobic exercise, which includes strength and resistance training, can firm, strengthen, and tone muscles, as well as improve bone strength, balance, and coordination. Examples of strength moves are push-ups, pull-ups, lunges, and bicep curls using dumbbells. Anaerobic exercise also include weight training, functional training, eccentric training, Interval training, sprinting, and high-intensity interval training increase short-term muscle strength.
  • Flexibility exercises stretch and lengthen muscles. Activities such as stretching help to improve joint flexibility and keep muscles limber. The goal is to improve the range of motion which can reduce the chance of injury.

Physical exercise can also include training that focuses on accuracy, agility, power, and speed.

Sometimes the terms ‘dynamic’ and ‘static’ are used. ‘Dynamic’ exercises such as steady running, tend to produce a lowering of the diastolic blood pressure during exercise, due to the improved blood flow. Conversely, static exercise (such as weight-lifting) can cause the systolic pressure to rise significantly (during the exercise).

Health effects

Physical exercise is important for maintaining physical fitness and can contribute to maintaining a healthy weight, regulating digestive health, building and maintaining healthy bone density, muscle strength, and joint mobility, promoting physiological well-being, reducing surgical risks, and strengthening the immune system. Some studies indicate that exercise may increase life expectancy and the overall quality of life. People who participate in moderate to high levels of physical exercise have a lower mortality rate compared to individuals who by comparison are not physically active. Moderate levels of exercise have been correlated with preventing aging by reducing inflammatory potential. The majority of the benefits from exercise are achieved with around 3500 metabolic equivalent (MET) minutes per week. For example, climbing stairs 10 minutes, vacuuming 15 minutes, gardening 20 minutes, running 20 minutes, and walking or bicycling for transportation 25 minutes on a daily basis would together achieve about 3000 MET minutes a week. A lack of physical activity causes approximately 6% of the burden of disease from coronary heart disease, 7% of type 2 diabetes, 10% of breast cancer and 10% of colon cancer worldwide. Overall, physical inactivity causes 9% of premature mortality worldwide.

Fitness

Individuals can increase fitness following increases in physical activity levels. Increases in muscle size from resistance training is primarily determined by diet and testosterone. This genetic variation in improvement from training is one of the key physiological differences between elite athletes and the larger population. Studies have shown that exercising in middle age leads to better physical ability later in life.

Cardiovascular system

The beneficial effect of exercise on the cardiovascular system is well documented. There is a direct correlation between physical inactivity and cardiovascular mortality, and physical inactivity is an independent risk factor for the development of coronary artery disease. Low levels of physical exercise increase the risk of cardiovascular diseases mortality.

Children who participate in physical exercise experience greater loss of body fat and increased cardiovascular fitness. Studies have shown that academic stress in youth increases the risk of cardiovascular disease in later years; however, these risks can be greatly decreased with regular physical exercise. There is a dose-response relation between the amount of exercise performed from approximately 700–2000 kcal of energy expenditure per week and all-cause mortality and cardiovascular disease mortality in middle-aged and elderly populations. The greatest potential for reduced mortality is in the sedentary who become moderately active. Studies have shown that since heart disease is the leading cause of death in women, regular exercise in aging women leads to healthier cardiovascular profiles. Most beneficial effects of physical activity on cardiovascular disease mortality can be attained through moderate-intensity activity (40–60% of maximal oxygen uptake, depending on age). Persons who modify their behavior after myocardial infarction to include regular exercise have improved rates of survival. Persons who remain sedentary have the highest risk for all-cause and cardiovascular disease mortality. According to the American Heart Association, exercise reduces blood pressure, LDL and total cholesterol, and body weight. It increases HDL cholesterol, insulin sensitivity, and exercise tolerance.

Immune system

Although there have been hundreds of studies on exercise and the immune system, there is little direct evidence on its connection to illness. Epidemiological evidence suggests that moderate exercise has a beneficial effect on the human immune system; an effect which is modeled in a J curve. Moderate exercise has been associated with a 29% decreased incidence of upper respiratory tract infections (URTI), but studies of marathon runners found that their prolonged high-intensity exercise was associated with an increased risk of infection occurrence. However, another study did not find the effect. Immune cell functions are impaired following acute sessions of prolonged, high-intensity exercise, and some studies have found that athletes are at a higher risk for infections. Studies have shown that strenuous stress for long durations, such as training for a marathon, can suppress the immune system by decreasing the concentration of lymphocytes. The immune systems of athletes and nonathletes are generally similar. Athletes may have slightly elevated natural killer cell count and cytolytic action, but these are unlikely to be clinically significant.

Vitamin C supplementation has been associated with lower incidence of URTIs in marathon runners.

Biomarkers of inflammation such as C-reactive protein, which are associated with chronic diseases, are reduced in active individuals relative to sedentary individuals, and the positive effects of exercise may be due to its anti-inflammatory effects. In individuals with heart disease, exercise interventions lower blood levels of fibrinogen and C-reactive protein, an important cardiovascular risk marker. The depression in the immune system following acute bouts of exercise may be one of the mechanisms for this anti-inflammatory effect.

Cancer

A systematic review evaluated 45 studies that examined the relationship between physical activity and cancer survivorship. According to the study results “There was consistent evidence from 27 observational studies that physical activity is associated with reduced all-cause, breast cancer–specific, and colon cancer–specific mortality”.

Epigenetic effects

Physical exercise was correlated with a lower methylation frequency of two tumor suppressor genes, CACNA2D3 and L3MBTL. Hypermethylation of CACNA2D3 is associated with gastric cancer, while hypermethylation of L3MBTL is associated with breast cancer, brain tumors and hematological malignancies. A recent study indicates that exercise results in reduced DNA methylation at CpG sites on genes associated with breast cancer.

Cancer cachexia

Physical exercise is becoming a widely accepted non-pharmacological intervention for the prevention and attenuation of cancer cachexia. “Cachexia is a multiorganic syndrome associated with cancer, characterized by inflammation, body weight loss (at least 5%) and muscle and adipose tissue wasting”. Exercise triggers the activation of the transcriptional coactivator peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), which suppresses FoxO- and NF-κB-dependent gene transcription during muscle atrophy that is induced by fasting or denervation; thus, PGC-1α may be a key intermediate responsible for the beneficial antiatrophic effects of physical exercise on cancer cachexia. The exercise-induced isoform PGC-1α4, which can repress myostatin and induce IGF1 and hypertrophy, is a potential drug target for treatment of cancer cachexia. Other factors, such as JUNB and SIRT1, that maintain skeletal muscle mass and promote hypertrophy are also induced with regular physical exercise.

Neurobiological

The neurobiological effects of physical exercise are numerous and involve a wide range of interrelated effects on brain structure, brain function, and cognition. A large body of research in humans has demonstrated that consistent aerobic exercise (e.g., 30 minutes every day) induces persistent improvements in certain cognitive functions, healthy alterations in gene expression in the brain, and beneficial forms of neuroplasticity and behavioral plasticity; some of these long-term effects include: increased neuron growth, increased neurological activity (e.g., c-Fos and BDNF signaling), improved stress coping, enhanced cognitive control of behavior, improved declarative, spatial, and working memory, and structural and functional improvements in brain structures and pathways associated with cognitive control and memory. The effects of exercise on cognition have important implications for improving academic performance in children and college students, improving adult productivity, preserving cognitive function in old age, preventing or treating certain neurological disorders, and improving overall quality of life.

In healthy adults, aerobic exercise has been shown to induce transient effects on cognition after a single exercise session and persistent effects on cognition following regular exercise over the course of several months. People who regularly perform aerobic exercise (e.g., running, jogging, brisk walking, swimming, and cycling) have greater scores on neuropsychological function and performance tests that measure certain cognitive functions, such as attentional control, inhibitory control, cognitive flexibility, working memory updating and capacity, declarative memory, spatial memory, and information processing speed. The transient effects of exercise on cognition include improvements in most executive functions (e.g., attention, working memory, cognitive flexibility, inhibitory control, problem solving, and decision making) and information processing speed for a period of up to 2 hours after exercising.

Aerobic exercise induces short- and long-term effects on mood and emotional states by promoting positive affect, inhibiting negative affect, and decreasing the biological response to acute psychological stress. Over the short-term, aerobic exercise functions as both an antidepressant and euphoriant, whereas consistent exercise produces general improvements in mood and self-esteem.

Regular aerobic exercise improves symptoms associated with a variety of central nervous system disorders and may be used as an adjunct therapy for these disorders. There is clear evidence of exercise treatment efficacy for major depressive disorder and attention deficit hyperactivity disorder. The American Academy of Neurology’s clinical practice guideline for mild cognitive impairment indicates that clinicians should recommend regular exercise (two times per week) to individuals who have been diagnosed with this condition. Reviews of clinical evidence also support the use of exercise as an adjunct therapy for certain neurodegenerative disorders, particularly Alzheimer’s disease and Parkinson’s disease. Regular exercise is also associated with a lower risk of developing neurodegenerative disorders. A large body of preclinical evidence and emerging clinical evidence supports the use of exercise therapy for treating and preventing the development of drug addictions. Regular exercise has also been proposed as an adjunct therapy for brain cancers.

Depression

Physical exercise has established efficacy as an antidepressant in individuals with depression and current medical evidence supports the use of exercise as both a preventive measure against and an adjunct therapy with antidepressant medication for depressive disorders. A July 2016 meta-analysis concluded that physical exercise improves overall quality of life in individuals with depression relative to controls. One systematic review noted that yoga may be effective in alleviating symptoms of prenatal depression. The biomolecular basis for exercise-induced antidepressant effects is believed to be a result of increased neurotrophic factor signaling, particularly brain-derived neurotrophic factor.

Continuous aerobic exercise can induce a transient state of euphoria, colloquially known as a “runner’s high” in distance running or a “rower’s high” in crew, through the increased biosynthesis of at least three euphoriant neurochemicals: anandamide (an endocannabinoid),β-endorphin (an endogenous opioid), and phenethylamine (a trace amine and amphetamine analog).

A systematic review noted that, although limited, some evidence suggests that the duration of engagement in a sedentary lifestyle is positively correlated with a risk of developing an anxiety disorder or experiencing anxiety symptoms. It noted that additional research is needed in order to confirm these findings.

Sleep

A 2010 review of published scientific research suggested that exercise generally improves sleep for most people, and helps sleep disorders such as insomnia. The optimum time to exercise may be 4 to 8 hours before bedtime, though exercise at any time of day is beneficial, with the possible exception of heavy exercise taken shortly before bedtime, which may disturb sleep. There is, in any case, insufficient evidence to draw detailed conclusions about the relationship between exercise and sleep.

According to a 2005 study, exercise is the most recommended alternative to sleeping pills for resolving insomnia. Sleeping pills are more costly than to make time for a daily routine of staying fit, and may have dangerous side effects in the long run. Exercise can be a healthy, safe and inexpensive way to achieve more and better sleep.

Excessive exercise

Too much exercise can be harmful. Without proper rest, the chance of stroke or other circulation problems increases, and muscle tissue may develop slowly. Extremely intense, long-term cardiovascular exercise, as can be seen in athletes who train for multiple marathons, has been associated with scarring of the heart and heart rhythm abnormalities. Specifically, high cardiac output has been shown to cause enlargement of the left and right ventricle volumes, increased ventricle wall thickness, and greater cardiac mass. These changes further result in myocardial cell damage in the lining of the heart, leading to scar tissue and thickened walls. During these processes, the protein troponin increases in the bloodstream, indicating cardiac muscle cell death and increased stress on the heart itself.

Inappropriate exercise can do more harm than good, with the definition of “inappropriate” varying according to the individual. For many activities, especially running and cycling, there are significant injuries that occur with poorly regimented exercise schedules. Injuries from accidents also remain a major concern, whereas the effects of increased exposure to air pollution seem only a minor concern.

In extreme instances, over-exercising induces serious performance loss. Unaccustomed overexertion of muscles leads to rhabdomyolysis (damage to muscle) most often seen in new army recruits. Another danger is overtraining, in which the intensity or volume of training exceeds the body’s capacity to recover between bouts. One sign of Overtraining Syndrome (OTS) is suppressed immune function, with an increased incidence of upper respiratory tract infection (URTI). An increased incidence of URTIs is also associated with high volume/intensity training, as well as with excessive exercise (EE), such as in a marathon. Marathon training requires the runner to build their intensity week to week which makes them more susceptible to injury the more they increase their mileage. A study shows that in the last 10–15 years up to 90% of marathon runners have suffered a physical injury from their training.

Stopping excessive exercise suddenly may create a change in mood. Exercise should be controlled by each body’s inherent limitations. While one set of joints and muscles may have the tolerance to withstand multiple marathons, another body may be damaged by 20 minutes of light jogging. This must be determined for each individual.

Too much exercise may cause a woman to miss her periods, a symptom known as amenorrhea. This is a very serious condition which indicates a woman is pushing her body beyond its natural boundaries.

Not only can excessive exercise cause physical damage, it can also cause psychological damage. Every athlete strives for perfection in their sport. This is what may begin their excessive exercising regime. If an athlete fails in this quest for perfection, this could result in anxiety, depression and low-self esteem. A study of 179 athletes, all of whom were Olympians or potential Olympians, was carried out in 2002 to find a relationship between perfectionism and sport-related competitive anxiety. It was found that athletes with lower self—esteem had higher personal standards and in comparison, those with high self-esteem had little concern in making mistakes or doubting themselves.

Mechanism of effects

Skeletal muscle

Resistance training and subsequent consumption of a protein-rich meal promotes muscle hypertrophy and gains in muscle strength by stimulating myofibrillar muscle protein synthesis (MPS) and inhibiting muscle protein breakdown (MPB). The stimulation of muscle protein synthesis by resistance training occurs via phosphorylation of the mechanistic target of rapamycin (mTOR) and subsequent activation of mTORC1, which leads to protein biosynthesis in the ribosome via phosphorylation of mTORC1’s immediate targets (the p70S6 kinase and the translation repressor protein 4EBP1). The suppression of muscle protein breakdown following food consumption occurs primarily via increases in plasma insulin; however, a suppression of MPB of comparable magnitude has also been shown to occur in humans from a sufficient elevation of plasma β-hydroxy β-methylbutyric acid.

Aerobic exercise induces mitochondrial biogenesis and an increased capacity for oxidative phosphorylation in the mitochondria of skeletal muscle, which is one mechanism by which aerobic exercise enhances submaximal endurance performance. These effects occur via an exercise-induced increase in the intracellular AMP:ATP ratio, thereby triggering the activation of AMP-activated protein kinase (AMPK) which subsequently phosphorylates peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), the master regulator of mitochondrial biogenesis.

Resistance training stimulates muscle protein synthesis (MPS) for a period of up to 48 hours following exercise (shown by dotted line).

Ingestion of a protein-rich meal at any point during this period will augment the exercise-induced increase in muscle protein synthesis (shown by solid lines).

Other peripheral organs

Developing research has demonstrated that many of the benefits of exercise are mediated through the role of skeletal muscle as an endocrine organ. That is, contracting muscles release multiple substances known as myokines which promote the growth of new tissue, tissue repair, and multiple anti-inflammatory functions, which in turn reduce the risk of developing various inflammatory diseases. Exercise reduces levels of cortisol, which causes many health problems, both physical and mental. Endurance exercise before meals lowers blood glucose more than the same exercise after meals. There is evidence that vigorous exercise (90–95% of VO2 max) induces a greater degree of physiological cardiac hypertrophy than moderate exercise (40 to 70% of VO2 max), but it is unknown whether this has any effects on overall morbidity and/or mortality. Both aerobic and anaerobic exercise work to increase the mechanical efficiency of the heart by increasing cardiac volume (aerobic exercise), or myocardial thickness (strength training). Ventricular hypertrophy, the thickening of the ventricular walls, is generally beneficial and healthy if it occurs in response to exercise.

Central nervous system

The persistent long-term neurobiological effects of regular physical exercise are believed to be mediated by transient exercise-induced increases in the concentration of neurotrophic factors (e.g., BDNF, IGF-1, VEGF, and GDNF) and other biomolecules in peripheral blood plasma, which subsequently cross the blood–brain barrier and blood–cerebrospinal fluid barrier and bind to their associated receptors in the brain. Upon binding to their receptors in cerebral vasculature and brain cells (i.e., neurons and glial cells), these biomolecules trigger intracellular signaling cascades that lead to neuroplastic biological responses – such as neurogenesis, synaptogenesis, oligodendrogenesis, and angiogenesis, among others – which ultimately mediate the exercise-induced improvements in cognitive function.  

Public health measures

Multiple component community-wide campaigns are frequently used in an attempt to increase a population’s level of physical activity. A 2015 Cochrane review, however, did not find evidence supporting a benefit. The quality of the underlying evidence was also poor. However, there is some evidence that school-based interventions can increase activity levels and fitness in children. Another Cochrane review found some evidence that certain types of exercise programmes, such as those involving gait, balance, co-ordination and functional tasks, can improve balance in older adults. Following progressive resistance training, older adults also respond with improved physical function. Survey of brief interventions promoting physical activity found that they are cost-effective, although there are variations between studies.

Environmental approaches appear promising: signs that encourage the use of stairs, as well as community campaigns, may increase exercise levels. The city of Bogotá, Colombia, for example, blocks off 113 kilometers (70 mi) of roads on Sundays and holidays to make it easier for its citizens to get exercise. These pedestrian zones are part of an effort to combat chronic diseases.

To identify which public health strategies are effective, a Cochrane overview of reviews is in preparation.

Physical exercise was said to decrease healthcare costs, increase the rate of job attendance, as well as increase the amount of effort women put into their jobs.

Children will mimic the behavior of their parents in relation to physical exercise. Parents can thus promote physical activity and limit the amount of time children spend in front of screens.

Overweight children who participate in physical exercise experience greater loss of body fat and increased cardiovascular fitness. According to the Centers for Disease Control and Prevention in the United States, both children and adults should do 60 minutes or more of physical activity each day. Implementing physical exercise in the school system and ensuring an environment in which children can reduce barriers to maintain a healthy lifestyle is essential.

Exercise trends

Running has become a popular form of exercise.

Worldwide there has been a large shift towards less physically demanding work. This has been accompanied by increasing use of mechanized transportation, a greater prevalence of labor saving technology in the home, and fewer active recreational pursuits.Personal lifestyle changes however can correct the lack of physical exercise.

Research in 2015 indicates integrating mindfulness to physical exercise interventions increases exercise adherence, self-efficacy and also has positive effects both psychologically and physiologically.

Social and cultural variation

Exercising looks different in every country, as do the motivations behind exercising. In some countries, people exercise primarily indoors, and in others, people exercise primarily outdoors. People may exercise for personal enjoyment, health and well-being, social interactions, competition or training, etc. These differences could potentially be attributed to geographic location, social tendencies, or otherwise.

In Colombia, citizens value and celebrate the outdoor environments of their country. In many instances, they utilize outdoor activities as social gatherings to enjoy nature and their communities. In Bogotá, Colombia, a 70-mile stretch of road known as the Ciclovía is shut down each Sunday for bicyclists, runners, rollerbladers, skateboarders and other exercisers to work out and enjoy their surroundings.

Similarly to Colombia, citizens of Cambodia tend to exercise socially outside. In this country, public gyms have become quite popular. People will congregate at these outdoor gyms not only to utilize the public facilities, but also to organize aerobics and dance sessions, which are open to the public.

Sweden has also begun developing outdoor gyms, called utegym. These gyms are free to the public and are often placed in beautiful, picturesque environments. People will swim in rivers, use boats, and run through forests to stay healthy and enjoy the natural world around them. This is especially possible in Sweden due to its geographical location.

Chinese exercise, particularly in the retired community, seems to be socially grounded. In the mornings, dances are held in public parks; these gatherings may include Latin dancing, ballroom dancing, tango, or even the jitterbug. Dancing in public allows people to interact with those with whom they would not normally interact, allowing for both health benefits and social benefits.

These sociocultural variations in physical exercise show how people in different geographic locations and social climates have varying motivations and methods of exercising. Physical exercise can improve health and well-being, as well as enhance community ties and appreciation of natural beauty.

Nutrition and recovery

Proper nutrition is as important to health as exercise. When exercising, it becomes even more important to have a good diet to ensure that the body has the correct ratio of macronutrients while providing ample micronutrients, in order to aid the body with the recovery process following strenuous exercise.

Active recovery is recommended after participating in physical exercise because it removes lactate from the blood more quickly than inactive recovery. Removing lactate from circulation allows for an easy decline in body temperature, which can also benefit the immune system, as an individual may be vulnerable to minor illnesses if the body temperature drops too abruptly after physical exercise.

History

The benefits of exercise have been known since antiquity. Dating back to 65 BCE, it was Marcus Cicero, Roman politician and lawyer, who stated: “It is exercise alone that supports the spirits, and keeps the mind in vigor.” Exercise was also seen to be valued later in history during the Dark Ages as a means of survival by the barbaric tribes of Northern Europe.

More recently, exercise was regarded as a beneficial force in the 19th century. After 1860, Archibald MacLaren opened a gymnasium at the University of Oxford and instituted a training regimen for 12 military officials at the university. This regimen was later assimilated into the training of the British Army. Several mass exercise movements were started in the early twentieth century as well. The first and most significant of these in the UK was the Women’s League of Health and Beauty, founded in 1930 by Mary Bagot Stack, that had 166,000 members in 1937.

However, the link between physical health and exercise (or lack of it) was only discovered in 1949 and reported in 1953 by a team led by Jerry Morris. Dr. Morris noted that men of similar social class and occupation (bus conductors versus bus drivers) had markedly different rates of heart attacks, depending on the level of exercise they got: bus drivers had a sedentary occupation and a higher incidence of heart disease, while bus conductors were forced to move continually and had a lower incidence of heart disease. This link had not previously been noted and was later confirmed by other researchers.

Other animals

Physical exercise has been shown to benefit a wide range of other mammals, as well as salmon, juvenile crocodiles, and at least one species of bird.

However, several studies have shown that lizards display no benefit from exercise, leading them to be termed “metabolically inflexible”. Indeed, damage from overtraining may occur following weeks of forced treadmill exercise in lizards.

A number of studies of both rodents and humans have demonstrated that individual differences in both ability and propensity for exercise (i.e., voluntary exercise) have some genetic basis.

Several studies of rodents have demonstrated that maternal or juvenile access to wheels that allow voluntary exercise can increase the propensity to run as adults. These studies further suggest that physical activity may be more “programmable” (for discussion, see Thrifty phenotype) than food intake.

See also

Notes

References

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  48. ^ Ferrara N, et al. (2008). “Exercise training promotes SIRT1 activity in aged rats”. Rejuven. Res. : 139–150. doi:10.1089/rej.2007.0576. 
  49. ^ a b c d e f g h Erickson KI, Hillman CH, Kramer AF (August 2015). “Physical activity, brain, and cognition”. Current Opinion in Behavioral Sciences. : 27–32. doi:10.1016/j.cobeha.2015.01.005. 
  50. ^ a b c d e Paillard T, Rolland Y, de Souto Barreto P (July 2015). “Protective Effects of Physical Exercise in Alzheimer’s Disease and Parkinson’s Disease: A Narrative Review”. J Clin Neurol. (3): 212–219. doi:10.3988/jcn.2015.11.3.212. PMC 4507374 . PMID 26174783. Aerobic physical exercise (PE) activates the release of neurotrophic factors and promotes angiogenesis, thereby facilitating neurogenesis and synaptogenesis, which in turn improve memory and cognitive functions. … Exercise limits the alteration in dopaminergic neurons in the substantia nigra and contributes to optimal functioning of the basal ganglia involved in motor commands and control by adaptive mechanisms involving dopamine and glutamate neurotransmission. 
  51. ^ a b McKee AC, Daneshvar DH, Alvarez VE, Stein TD (January 2014). “The neuropathology of sport”. Acta Neuropathol. (1): 29–51. doi:10.1007/s00401-013-1230-6. PMC 4255282 . PMID 24366527. The benefits of regular exercise, physical fitness and sports participation on cardiovascular and brain health are undeniable … Exercise also enhances psychological health, reduces age-related loss of brain volume, improves cognition, reduces the risk of developing dementia, and impedes neurodegeneration. 
  52. ^ a b Denham J, Marques FZ, O’Brien BJ, Charchar FJ (February 2014). “Exercise: putting action into our epigenome”. Sports Med. (2): 189–209. doi:10.1007/s40279-013-0114-1. PMID 24163284. Aerobic physical exercise produces numerous health benefits in the brain. Regular engagement in physical exercise enhances cognitive functioning, increases brain neurotrophic proteins, such as brain-derived neurotrophic factor (BDNF), and prevents cognitive diseases . Recent findings highlight a role for aerobic exercise in modulating chromatin remodelers . … These results were the first to demonstrate that acute and relatively short aerobic exercise modulates epigenetic modifications. The transient epigenetic modifications observed due to chronic running training have also been associated with improved learning and stress-coping strategies, epigenetic changes and increased c-Fos-positive neurons … Nonetheless, these studies demonstrate the existence of epigenetic changes after acute and chronic exercise and show they are associated with improved cognitive function and elevated markers of neurotrophic factors and neuronal activity (BDNF and c-Fos). … The aerobic exercise training-induced changes to miRNA profile in the brain seem to be intensity-dependent . These few studies provide a basis for further exploration into potential miRNAs involved in brain and neuronal development and recovery via aerobic exercise. 
  53. ^ a b c d e Gomez-Pinilla F, Hillman C (January 2013). “The influence of exercise on cognitive abilities”. Compr. Physiol. (1): 403–428. doi:10.1002/cphy.c110063. PMC 3951958 . PMID 23720292. 
  54. ^ a b Erickson KI, Leckie RL, Weinstein AM (September 2014). “Physical activity, fitness, and gray matter volume”. Neurobiol. Aging. 35 Suppl 2: S20–528. doi:10.1016/j.neurobiolaging.2014.03.034. PMC 4094356 . PMID 24952993. Retrieved 9 December 2014. 
  55. ^ a b c Guiney H, Machado L (February 2013). “Benefits of regular aerobic exercise for executive functioning in healthy populations”. Psychon Bull Rev. (1): 73–86. doi:10.3758/s13423-012-0345-4. PMID 23229442. 
  56. ^ a b Erickson KI, Miller DL, Roecklein KA (2012). “The aging hippocampus: interactions between exercise, depression, and BDNF”. Neuroscientist. (1): 82–97. doi:10.1177/1073858410397054. PMC 3575139 . PMID 21531985. 
  57. ^ a b Buckley J, Cohen JD, Kramer AF, McAuley E, Mullen SP (2014). “Cognitive control in the self-regulation of physical activity and sedentary behavior”. Front Hum Neurosci. : 747. doi:10.3389/fnhum.2014.00747. PMC 4179677 . PMID 25324754. 
  58. ^ a b c Cox EP, O’Dwyer N, Cook R, Vetter M, Cheng HL, Rooney K, O’Connor H (August 2016). “Relationship between physical activity and cognitive function in apparently healthy young to middle-aged adults: A systematic review”. J. Sci. Med. Sport. (8): 616–628. doi:10.1016/j.jsams.2015.09.003. PMID 26552574. A range of validated platforms assessed CF across three domains: executive function (12 studies), memory (four studies) and processing speed (seven studies). … In studies of executive function, five found a significant ES in favour of higher PA, ranging from small to large. Although three of four studies in the memory domain reported a significant benefit of higher PA, there was only one significant ES, which favoured low PA. Only one study examining processing speed had a significant ES, favouring higher PA.
    CONCLUSIONS: A limited body of evidence supports a positive effect of PA on CF in young to middle-aged adults. Further research into this relationship at this age stage is warranted. …
    Significant positive effects of PA on cognitive function were found in 12 of the 14 included manuscripts, the relationship being most consistent for executive function, intermediate for memory and weak for processing speed.
     
  59. ^ a b c d Schuch FB, Vancampfort D, Rosenbaum S, Richards J, Ward PB, Stubbs B (July 2016). “Exercise improves physical and psychological quality of life in people with depression: A meta-analysis including the evaluation of control group response”. Psychiatry Res. : 47–54. doi:10.1016/j.psychres.2016.04.054. PMID 27155287. Exercise has established efficacy as an antidepressant in people with depression. … Exercise significantly improved physical and psychological domains and overall QoL. … The lack of improvement among control groups reinforces the role of exercise as a treatment for depression with benefits to QoL. 
  60. ^ Pratali L, Mastorci F, Vitiello N, Sironi A, Gastaldelli A, Gemignani A (November 2014). “Motor Activity in Aging: An Integrated Approach for Better Quality of Life”. Int. Sch. Res. Notices. : 257248. doi:10.1155/2014/257248. PMC 4897547 . PMID 27351018. Research investigating the effects of exercise on older adults has primarily focused on brain structural and functional changes with relation to cognitive improvement. In particular, several cross-sectional and intervention studies have shown a positive association between physical activity and cognition in older persons and an inverse correlation with cognitive decline and dementia . Older adults enrolled in a 6-month aerobic fitness intervention increased brain volume in both gray matter (anterior cingulate cortex, supplementary motor area, posterior middle frontal gyrus, and left superior temporal lobe) and white matter (anterior third of corpus callosum) . In addition, Colcombe and colleagues showed that older adults with higher cardiovascular fitness levels are better at activating attentional resources, including decreased activation of the anterior cingulated cortex. One of the possible mechanisms by which physical activity may benefit cognition is that physical activity maintains brain plasticity, increases brain volume, stimulates neurogenesis and synaptogenesis, and increases neurotrophic factors in different areas of the brain, possibly providing reserve against later cognitive decline and dementia . 
  61. ^ a b c d Basso JC, Suzuki WA (March 2017). “The Effects of Acute Exercise on Mood, Cognition, Neurophysiology, and Neurochemical Pathways: A Review”. Brain Plasticity. (2): 127–152. doi:10.3233/BPL-160040 . Lay summary – Can A Single Exercise Session Benefit Your Brain? (12 June 2017). A large collection of research in humans has shown that a single bout of exercise alters behavior at the level of affective state and cognitive functioning in several key ways. In terms of affective state, acute exercise decreases negative affect, increases positive affect, and decreases the psychological and physiological response to acute stress . These effects have been reported to persist for up to 24 hours after exercise cessation . In terms of cognitive functioning, acute exercise primarily enhances executive functions dependent on the prefrontal cortex including attention, working memory, problem solving, cognitive flexibility, verbal fluency, decision making, and inhibitory control . These positive changes have been demonstrated to occur with very low to very high exercise intensities , with effects lasting for up to two hours after the end of the exercise bout (Fig. 1A) . Moreover, many of these neuropsychological assessments measure several aspects of behavior including both accuracy of performance and speed of processing. McMorris and Hale performed a meta-analysis examining the effects of acute exercise on both accuracy and speed of processing, revealing that speed significantly improved post-exercise, with minimal or no effect on accuracy . These authors concluded that increasing task difficulty or complexity may help to augment the effect of acute exercise on accuracy. … However, in a comprehensive meta-analysis, Chang and colleagues found that exercise intensities ranging from very light (93% MHR) have all been reported to improve cognitive functioning . 
  62. ^ Cunha GS, Ribeiro JL, Oliveira AR (June 2008). “”. Arq Bras Endocrinol Metabol (in Portuguese). (4): 589–598. PMID 18604371. Interestingly, some symptoms of OT are related to beta-endorphin (beta-end(1-31)) effects. Some of its effects, such as analgesia, increasing lactate tolerance, and exercise-induced euphoria, are important for training. 
  63. ^ Boecker H, Sprenger T, Spilker ME, Henriksen G, Koppenhoefer M, Wagner KJ, Valet M, Berthele A, Tolle TR (2008). “The runner’s high: opioidergic mechanisms in the human brain”. Cereb. Cortex. (11): 2523–2531. doi:10.1093/cercor/bhn013. PMID 18296435. The runner’s high describes a euphoric state resulting from long-distance running. 
  64. ^ a b c Josefsson T, Lindwall M, Archer T (2014). “Physical exercise intervention in depressive disorders: meta-analysis and systematic review”. Scand J Med Sci Sports. (2): 259–272. doi:10.1111/sms.12050. PMID 23362828. 
  65. ^ a b Rosenbaum S, Tiedemann A, Sherrington C, Curtis J, Ward PB (2014). “Physical activity interventions for people with mental illness: a systematic review and meta-analysis”. J Clin Psychiatry. (9): 964–974. doi:10.4088/JCP.13r08765. PMID 24813261. This systematic review and meta-analysis found that physical activity reduced depressive symptoms among people with a psychiatric illness. The current meta-analysis differs from previous studies, as it included participants with depressive symptoms with a variety of psychiatric diagnoses (except dysthymia and eating disorders). … This review provides strong evidence for the antidepressant effect of physical activity; however, the optimal exercise modality, volume, and intensity remain to be determined. …
    Conclusion
    Few interventions exist whereby patients can hope to achieve improvements in both psychiatric symptoms and physical health simultaneously without significant risks of adverse effects. Physical activity offers substantial promise for improving outcomes for people living with mental illness, and the inclusion of physical activity and exercise programs within treatment facilities is warranted given the results of this review.
     
  66. ^ a b Szuhany KL, Bugatti M, Otto MW (October 2014). “A meta-analytic review of the effects of exercise on brain-derived neurotrophic factor”. J Psychiatr Res. 60C: 56–64. doi:10.1016/j.jpsychires.2014.10.003. PMC 4314337 . PMID 25455510. Consistent evidence indicates that exercise improves cognition and mood, with preliminary evidence suggesting that brain-derived neurotrophic factor (BDNF) may mediate these effects. The aim of the current meta-analysis was to provide an estimate of the strength of the association between exercise and increased BDNF levels in humans across multiple exercise paradigms. We conducted a meta-analysis of 29 studies (N = 1111 participants) examining the effect of exercise on BDNF levels in three exercise paradigms: (1) a single session of exercise, (2) a session of exercise following a program of regular exercise, and (3) resting BDNF levels following a program of regular exercise. Moderators of this effect were also examined. Results demonstrated a moderate effect size for increases in BDNF following a single session of exercise (Hedges’ g = 0.46, p 
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