Regular physical activity provides many health benefits and is an important part of maintaining a healthy lifestyle. Some of the well-known benefits of regular exercise include improved cardiovascular health, increased muscle and bone strength, weight management, reduced risk of chronic diseases, better sleep, and improved mental health. However, not all claimed benefits of exercise stand up to scientific scrutiny. This article will examine some commonly cited results of regular physical activity and determine which is not supported by evidence.
Improved Cardiovascular Health
Regular physical activity has been extensively studied and proven to provide cardiovascular benefits. Exercise helps strengthen the heart muscle, lower blood pressure, improve blood lipid profiles, and reduce inflammation.
During exercise, the heart rate increases to pump more oxygenated blood through the body. This puts a temporary stress on the cardiovascular system. With regular exercise, the heart becomes more efficient and effective at pumping blood. The resting heart rate lowers, stroke volume increases, and blood pumps more effectively through the arteries and vessels.
Evidence shows that 150 minutes of moderate intensity aerobic exercise per week can lower blood pressure in those with hypertension. Even small reductions in blood pressure can reduce the risk of stroke and heart disease. Regular activity also increases HDL (good) cholesterol, reduces triglycerides, and promotes healthy blood flow.
The benefits to heart health are clear. Regular physical activity improves cardiovascular fitness and significantly lowers the risk of heart disease.
Increased Muscle and Bone Strength
Regular physical activity that incorporates resistance training is highly effective for building stronger muscles and bones. When muscles are worked against resistance, they adapt by getting bigger and stronger.
As we age, muscle mass naturally declines. Loss of muscle mass can lead to feeling weak, greater risk of falls and fractures, and loss of mobility. However, regular strength training helps counteract this age-related muscle loss. It also helps strengthen bone by promoting bone formation.
Bone is living tissue that responds to stress by reforming to become stronger. Weight bearing aerobic exercise and resistance training puts controlled stress on bones that stimulates rebuilding. Regular physical activity, particularly in youth and adolescence, is crucial for reaching peak bone mass. Stronger bones developed earlier in life reduce the risk of osteoporosis later on.
Multiple studies confirm that adults who perform resistance training 2-3 times per week can significantly increase muscle mass and strength. Similar training also improves bone mineral density. The resulting increases in muscle and bone strength reduce the risk of falls and fractures.
Weight Management
Regular physical activity is a key element of successful weight loss and weight maintenance. To lose weight, more energy must be expended than consumed. Physical activity, along with a healthy diet, creates a calorie deficit and allows the body to burn stored fat.
Exercise also helps in weight management by building muscle. Muscle tissue is more metabolically active than fat, burning more calories at rest. The more muscle built through resistance training, the higher daily calorie burn. This makes it easier to maintain a lower body weight.
While exercise alone is not sufficient for major weight loss, it is extremely difficult to lose substantial weight through calorie reduction alone. Physical activity provides crucial burn, builds calorie burning muscle, and is one of the best predictors of maintained weight loss.
Overwhelming evidence confirms that regular physical activity enables effective weight management.
Reduced Risk of Chronic Diseases
Lack of physical activity has been identified as the fourth leading risk factor for global mortality. Physical inactivity increases the likelihood of many chronic diseases such as heart disease, diabetes, obesity, hypertension, cancer, and osteoporosis.
Regular exercise helps prevent chronic disease by reducing inflammation. While acute inflammation is needed for healing, chronic inflammation contributes to the development of disease. Moderate exercise has been shown to decrease inflammatory markers.
Staying active also helps regulate blood sugar and insulin sensitivity, reducing the risk of developing type 2 diabetes. Exercise even appears to positively effect gene expression, lowering the susceptibility for chronic disease.
In addition to disease prevention, exercise is often prescribed as a non-drug treatment for many chronic diseases. Physical activity reduces disease progression through similar mechanisms that lower risk. The constant bodily movement stimulates adaptation and resilience.
Overall, scientific consensus concludes regular physical activity plays an integral role in reducing the risk of various chronic diseases.
Better Sleep Quality
Research has found that exercising regularly can help improve the quality and duration of sleep. However, the type and timing of physical activity plays an important role.
Moderate aerobic exercise during the day appears to be best for promoting good sleep. In contrast, vigorous late-day workouts may interfere with sleep due to increased heart rate, adrenaline, and body temperature. Strength training routines performed too close to bedtime may also negatively impact sleep.
How does proper daytime exercise improve sleep? Physical activity helps regulate neurotransmitter and hormone levels, synchronize circadian rhythms, and raise body temperature. These factors all influence sleep/wake cycles and sleep quality. Exercising adds to the homeostatic drive for sleep. As an energy expenditure, it primes the body for recuperative rest.
While excessive high-intensity exercise may disrupt sleep, ample research concludes moderate daytime exercise improves sleep quality and duration for many people.
Improved Mental Health
Exercise has also been shown to benefit various aspects of mental health. Studies demonstrate regular physical activity can reduce anxiety symptoms, relieve depression, and improve cognitive function.
The mental health benefits appear significant enough that exercise is considered a frontline treatment for mild-to-moderate depression and anxiety. Moderate physical activity stimulates neurotransmitter release and new neuron growth in the hippocampus. This may explain the anti-anxiety and antidepressant effects from regular exercise.
Additionally, exercise enhances learning and memory retention. People who exercise demonstrate improved focus, decision-making, information processing, and executive functioning. Exercise seems to stimulate the production of growth factors that promote the health of brain cells involved in cognitive tasks.
The research overwhelmingly concludes physical activity benefits mental health through several interrelated mechanisms. While prescription medications are sometimes necessary, exercise should be considered a fundamental first-line treatment for maintaining mental health.
Stronger Immune System
A stronger immune system is often cited as another health benefit of regular physical activity. While moderate exercise does help avoid chronic inflammation and disease, the relationship with immune system strength is more nuanced.
Mild to moderate exercise enhances activity of certain immune cells like macrophages and neutrophils. However, this only occurs during each individual training session. Following exercise, various immune parameters return to normal baseline levels relatively quickly.
Vigorous high-intensity exercise for prolonged periods can actually suppress immune function for several hours. This transient immune suppression opens a window of increased infection risk. Professional endurance athletes are susceptible following races or intensive training blocks.
Rigorous physical training routines needed for elite athletic competition have immunosuppressive effects, particularly when accompanied by inadequate recovery. More moderate recreational exercise does not appear to produce meaningful long-term immune system strengthening. While regular activity provides many health benefits, scientific evidence does not support the claim of directly strengthening the immune system.
Conclusion
In summary, the well-established health benefits of regular physical activity include:
– Improved cardiovascular health
– Increased muscle and bone strength
– Weight management
– Reduced risk of chronic diseases
– Better sleep quality
– Improved mental health
While exercise plays a role in avoiding inflammation and illness, evidence does not support the direct strengthening of the immune system. Strenuous endurance training routines can even be temporarily immunosuppressive following sessions.
All the other commonly promoted health benefits of regular exercise are strongly supported by extensive research. A combination of moderate aerobic activity and resistance training provides the best results, especially when maintained consistently over the long term. Exercise supports practically every aspect of physical and mental health due to the body’s intrinsic drive for positive adaptation and self-preservation.
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