What Happens in Your Body When You Exercise?

  • One of the key health benefits of exercise is that it helps normalize your glucose, insulin, and leptin levels by optimizing insulin/leptin receptor sensitivity

Exercise-improved insulin/leptin receptor sensitivity is perhaps the most important factor for optimizing your overall health and preventing chronic disease

Exercise also encourages your brain to work at optimum capacity by causing your nerve cells to multiply, strengthening their interconnections, and protecting them from damage.

Unexpected side effects of exercise include improved sexual function, changes in gene expression, clearer skin, and improved mood and sleep

Research shows that the “secret” to increased productivity and happiness on any given day is a long-term investment in regular exercise, and a little each day appears to go further than a lot once or twice a week

PURPOSE OF REVIEW:

This systematic review reports the most recent literature regarding the effects of physical exercise on muscle strength, body composition, physical functioning and inflammation in older adults. All articles were assessed for methodological quality and where possible effect size was calculated.


RECENT FINDINGS:

Thirty-four articles were included – four involving frail, 24 healthy and five older adults with a specific disease. One reported on both frail and nonfrail patients. Several types of exercise were used: resistance training, aerobic training, combined resistance training and aerobic training and others. In frail older persons, moderate-to-large beneficial exercise effects were noted on inflammation, muscle strength and physical functioning. In healthy older persons, effects of resistance training (most frequently investigated) on inflammation or muscle strength can be influenced by the exercise modalities (intensity and rest interval between sets). Muscle strength seemed the most frequently used outcome measure, with moderate-to-large effects obtained regardless the exercise intervention studied. Similar effects were found in patients with specific diseases.

includes changes in your:

• Muscles, which use glucose and ATP for contraction and movement. To create more ATP, your body needs extra oxygen, so breathing increases and your heart starts pumping more blood to your muscles.

Without sufficient oxygen, lactic acid will form instead. Tiny tears in your muscles make them grow bigger and stronger as they heal.

• Lungs. As your muscles call for more oxygen (as much as 15 times more oxygen than when you’re at rest), your breathing rate increases. Once the muscles surrounding your lungs cannot move any faster, you’ve reached what’s called your VO2 max—your maximum capacity of oxygen use. The higher your VO2 max, the fitter you are.

• Heart. As mentioned, your heart rate increases with physical activity to supply more oxygenated blood to your muscles. The fitter you are, the more efficiently your heart can do this, allowing you to work out longer and harder. As a side effect, this increased efficiency will also reduce your resting heart rate. Your blood pressure will also decrease as a result of new blood vessels forming.

• Brain. The increased blood flow also benefits your brain, allowing it to almost immediately function better. As a result, you tend to feel more focused after a workout. Furthermore, exercising regularly will promote the growth of new brain cells. In your hippocampus, these new brain cells help boost memory and learning. As stated in the featured article:

“When you work out regularly, your brain gets used to this frequent surge of blood and adapts by turning certain genes on or off. Many of these changes boost brain cell function and protect from diseases such as Alzheimer’s, Parkinson’s or even stroke, and ward off age-related decline.”

A number of neurotransmitters are also triggered, such as endorphins, serotonin, dopamine, glutamate, and GABA. Some of these are well-known for their role in mood control. Exercise, in fact, is one of the most effective prevention and treatment strategies for depression.

• Joints and bones, as exercise can place as much as five or six times more than your body weight on them. Peak bone mass is achieved in adulthood and then begins a slow decline, but exercise can help you to maintain healthy bone mass as you get older.

Weight-bearing exercise is actually one of the most effective remedies against osteoporosis, as your bones are very porous and soft, and as you get older your bones can easily become less dense and hence, more brittle — especially if you are inactive.

SUMMARY:

Exercise has moderate-to-large effects on muscle strength, body composition, physical functioning and inflammation in older adults. Future studies should focus on the influence of specific exercise modalities and target the frail population more.