Benefits of physical activity

The benefits of physical exercise, especially aerobic exercise or pilates, have positive effects on brain function on multiple fronts, ranging from the molecular to the behavioral level. According to a study conducted by the Department of Exercise Science at the University of Georgia, even briefly exercising for 20 minutes facilitates information processing and memory functions.[4]

Exercise affects the brain on multiple fronts. It increases the heart rate, which pumps more oxygen to the brain. It also aids the bodily release of a plethora of hormones, all of which participate in aiding and providing a nourishing environment for the growth of brain cells.[5]

Physical activity of any intensity is beneficial. It can enhance sleep, cognitive health, and quality of life, regardless of age or fitness level. It can lower the risk of cognitive decline, including dementia. Adults who are inactive have nearly twice as many cases of cognitive deterioration as adults who are active. It's recommended that the majority of adults engage in 150 minutes per week of physical activity of a moderate level. This can be divided into 5 days a week of daily, 30-minute sessions. [6]

Exercise stimulates brain plasticity by stimulating the growth of new connections between cells in a wide array of important cortical areas of the brain. Research from UCLA demonstrated that exercise increased growth factors in the brain, making it easier for the brain to grow new neuronal connections.[7]

Exercise can improve cognitive skills, decrease chances of dementia, and reduce damage and deterioration of brain tissue. Scientists believe that by maintaining physical fitness, it keeps the blood flowing normally to brain tissue.[8] When the blood flows normally to the brain tissue, it reduces the risk of damage and deterioration. Blood flow is very important when it comes to keeping the brain young and healthy. There have also been studies that show that aerobic exercise stimulates the release of growth hormones, which continues to improve brain function. When getting to a certain age, it is important that one exercises regularly to keep the brain strong and well functioning, rather than deteriorating.

The CDC website states, "Every little bit counts. Even some chores such as light yard work (raking and bagging leaves or using a lawn mower) and gardening can help you get active"[9]

Some of the benefits of physical activity on brain health happen right after a session of moderate-to-vigorous physical activity. Benefits include improved thinking or cognition for children ages 6-13 and reduced short-term feelings of anxiety for adults. Regular physical activity can keep thinking, learning, and judgment skills sharp with age. It can also reduce the risk of depression and anxiety and improve sleep.[10]

Both diet and physical activity play a critical role in maintaining healthy body weight, losing excess body weight, or maintaining successful weight loss.[11] Physical activity helps control weight by using excess calories that would otherwise be stored as fat. Most foods consumed contain calories, and most activities burn calories, including sleeping, breathing, and digesting food. Balancing the calories consumed with the calories used through physical activity can help someone reach and maintain a healthy weight.[12]

Muscle is crucial to the human body. Muscle is heavier than fat, so by losing fat and gaining an equal amount of muscle, one could gain weight. However, the body could appear slimmer and leaner.Physical activity is not only used for losing weight, but also for gaining weight. By having a high protein intake, one can put stress on muscle fibers, by doing an exercise regimen that will cause them to tear. This is why one may feel sore, as the muscle fibers are starting the process of tearing and healing. Once the muscle fibers heal, growth and gain in weight will appear. Because muscle mass is denser than fat mass, adding lean muscle can cause weight gain.

Regular physical exercise is associated with numerous health benefits to reduce the progression and development of obesity, T2D, and CVD. Several randomized clinical trials have demonstrated that lifestyle interventions, including moderate exercise and a healthy diet, improve cardiovascular health in at-risk populations. Individuals with metabolic syndrome who participated in a 4-month program of either a diet (caloric restriction) or exercise intervention had reduced adiposity, decreased systolic, diastolic and mean arterial blood pressure, and lower total and low-density lipoprotein (LDL) cholesterol lipid profiles compared to the control group. Both the diet and exercise intervention improve these cardiovascular outcomes to a similar extent.[17]

Several previous studies have investigated the effects of diet and exercise, independently or in combination, on metabolic and cardiovascular health and have determined that diet, exercise, or a combination of diet and exercise induces weight loss, decreases visceral adiposity, lowers plasma triglycerides, plasma glucose, HDL levels, and blood pressure, and improves VO2max. Importantly, several of these beneficial effects of exercise are evident independent of weight loss. Studies have shown that exercise can improve metabolic and cardiovascular health independent of changes in body weight, including improved glucose homeostasis, endothelial function, blood pressure, and HDL levels. These data indicate exercise, independent of changes in body mass, results in significant improvements in cardiovascular and metabolic health. Although a detailed analysis of the vast impact of diet on cardiometabolic health is outside the scope of this review, the importance of diet and exercise in tandem should not be ignored, as many studies have shown that cardiometabolic health is improved to a higher extent in response to a combined diet and exercise programs compared to either intervention alone.[17]

Exercise has a similar effect on cardiovascular improvements in lean and overweight normoglycemic subjects. In a 1-year study of non-obese individuals, a 16–20% increase in energy expenditure (of any form of exercise) with no diet intervention resulted in a 22.3% decrease in body fat mass and reduced LDL cholesterol, total cholesterol/HDL ratio, and C-reactive protein concentrations, all risk factors associated with CVD. In overweight individuals, 7–9 months of low-intensity exercise (walking ~19 km per week at 40–55% VO2peak) significantly increased cardiorespiratory fitness compared to sedentary individuals. Together these data indicate that exercise interventions decrease the risk or severity of CVD in subjects who are lean, obese, or have type 2 diabetes.[17]

Exercise is also an important therapeutic treatment for patients who have cardiovascular diseases. A systematic review of 63 studies found that exercise-based cardiac rehabilitation improved cardiovascular function. These studies consisted of various forms of aerobic exercise at a range of intensities (from 50 to 95% VO2), over a multitude of time periods (1–47 months). Overall, exercise significantly reduced CVD-related mortality, decreased risk of MI, and improved quality of life. Another study looked specifically in patients with atherosclerosis post-revascularization surgery. Patients who underwent 60 min of exercise per day on a cycle ergometer for 4 weeks had an increase blood flow reserve (29%) and improved endothelium-dependent vasodilatation. A recent study provided personalized aerobic exercise rehabilitation programs for patients who had an acute myocardial infarction for 1 year after a coronary intervention surgery. The patients who underwent the exercise rehabilitation program had increased ejection fraction (60.81 vs. 53% control group), increased exercise tolerance, and reduced cardiovascular risk factors 6 months after starting the exercise rehabilitation program. This improvement in cardiovascular health in patients with atherosclerosis or post-MI is likely the result of increased myocardial perfusion in response to exercise, however, more research is required to fully understand these mechanisms.[18]

One defining characteristic of heart failure is exercise intolerance, which resulted in a prescription of bed rest for these patients until the 1950s. However, it has now been shown that a monitored rehabilitation program using moderate intensity exercise is safe for heart failure patients, and this has now become an important therapeutic for patients with heart failure. Meta-analyses and systemic reviews have shown that exercise training in heart failure patients is associated with improved quality of life, reduced risk of hospitalization and decreased rates of long-term mortality. One study of heart failure patients found that aerobic exercise (walking or cycling) at 60–70% of heart rate reserve 3–5 times per week for over 3 years led to improved health and overall quality of life (determined by a self-reported Kansas City Cardiomyopathy Questionnaire, a 23-question disease-specific questionnaire). Other studies have shown that exercise-based rehabilitation at a moderate intensity in heart failure patients improves cardiorespiratory fitness and increases both exercise endurance capacity and VO2max (12–31% increase).[18]

More recent studies have examined the effects of high-intensity exercise on patients with heart failure. A recent study found that 12 weeks of high-intensity interval training (HIIT) in heart failure patients (with reduced ejection fraction) was well-tolerated and had similar benefits compared to patients who underwent moderate continuous exercise (MCE) training, including improved left ventricular remodeling and aerobic capacity. A separate study found that 4 weeks of HIIT in heart failure patients with preserved ejection fraction improved VO2peak and reduced diastolic dysfunction compared to both pre-training values and compared to the MCE group. These studies indicate that both moderate and high intensity exercise training improve cardiovascular function in heart failure patients, likely related to increased endothelium-dependent vasodilation and improved aerobic capacity.[18]

Routine physical activity is important for building strong bones and muscles in children, but it is equally important with older adults. Bones and muscles work together to support daily movements. Physical activity strengthens muscles. Bones adapt by building more cells, and as a result, both become stronger. Strong bones and muscles protect against injury and improves balance and coordination. In addition, active adults experience less joint stiffness and improved flexibility. This becomes especially important with age, as it helps to prevent falls and the broken bones that may result. For those with arthritis, exercise that keeps the muscles around the joint strong can act like a brace that will react to movement without the use of an actual brace.[19]

The ability to perform daily activities and maintain independence requires strong muscles, balance and endurance. Regular physical activity or exercise helps to improve and prevent the decline of muscle strength, balance and endurance, all risk factors for falling. Balance plays an important role in everyday activities such as walking, getting up out of a chair or leaning over to pick something up. Balance problems can reduce independence by interfering with activities of daily living. Regular physical activity can improve balance and reduce the risk of falling.[20]

Exercise increases the chances of surviving cancer. If one exercise during the early stages of cancer treatment it may allow time to reduce the detrimental side effects of the chemotherapy. It also improves physical functions along with reducing distress and fatigue.[21] Studies have shown that exercise has the possibility to improve the chemotherapy drug uptake, thanks to the increase in the peripheral circulation.[21] This also makes changes to tumors vasculature from the increase of cardio and blood pressure.

Exercise triggers an increase in body temperature, and the post-exercise drop in temperature may promote falling asleep. Exercise may also reduce insomnia by decreasing arousal, anxiety and depressive symptoms. Insomnia is commonly linked with elevated arousal, anxiety, and depression, and exercise has effects on reducing these symptoms in the general population.[22] These issues count among the most common among most of population. Anxiety disorders are the most common mental illness in the U.S., affecting 40 million adults in the United States age 18 and older, or 18.1% of the population every year.[23] A 2010 review suggested that exercise generally improved sleep for most people, and may help with insomnia, but there is insufficient evidence to draw detailed conclusions about the relationship between exercise and sleep.[24][25] A 2020 systematic review and meta-analysis suggested that physical activity has little association with sleep in healthy children.[26] However, there have been several research findings indicating that certain forms of physical activity can improve the quality and duration of sleep.[27] In fact, a 2019 study at The Federal University of São Paulo concluded that moderate physical activity resulted in an increase in sleep efficiency and duration in adults diagnosed with insomnia.[28] The duration refers to the hours of sleep a person gets on a nightly basis, while the quality indicates how well or sufficient it was.[29] Having poor sleep quality can lead to negative short term consequences like emotional distress and performance deficits. The psychosocial issues associated with these consequences can vary between adults, adolescents, and children. Some of the long term effects of poor sleep quality can lead to conditions like hypertension, metabolic syndrome, and even weight-related issues.[30]