How Exercise Re-Programs Your Body's Chemistry:
The powers of
a good sweat are well-documented: Regular physical activity can help lower your blood pressure and cholesterol levels, help you achieve and maintain a healthy weight, and reduce your risk of depression, heart disease, stroke, and cancer. While weight loss and blood sugar control are two reasons for these benefits, there's another one that most people don't know about: When you move, your muscles release hormones. Here are three you’re producing every time you work up a sweat.
The hormone: Irisin
What it is: Exercise causes it to break off into your bloodstream and circulate throughout your body. Hence its nickname: the “exercise hormone.”
How it works: One recent study found that irisin reprograms fat cells to burn energy instead of storing it, which explains how working out boosts your metabolic rate and helps you shed flab. Another recent U.K. study discovered that people with higher levels of irisin in their blood are more likely to have longer telomeres—caps at the end of chromosomes that shorten as you age. Many health issues—including cancer, heart disease, and Alzheimer’s—are associated with shorter telomere length.
Maximize the benefits: “Focus on the large muscle groups since they contain more individual muscle cells,” says study author James Brown, Ph.D.
this is just a sample....
I can write a lot better