Science shows that physical activity can reduce your risk of dying early from leading causes of death, like heart disease and some cancers. This is remarkable because only a few lifestyle choices have as large an impact on your health as physical activity. People who are physically active for about 150 minutes a week have a 33% lower risk of all-cause mortality than those who are physically inactive.
Physical activity has numerous beneficial physiologic effects. Most widely appreciated are its effects on the cardiovascular and musculoskeletal systems, but benefits on the functioning of metabolic, endocrine, and immune systems are also considerable.
Many of the beneficial effects of exercise training—from both endurance and resistance activities—diminish within 2 weeks if physical activity is substantially reduced, and effects disappear within 2 to 8 months if physical activity is not resumed.