environmentalist. 1  a person who accepts the theory that environment is of overriding importance in determining individual characteristics. 2  a person working to solve environmental problems, as air and water pollution, the exhaustion of natural resources, and uncontrolled population growth.
1 Muscle helps you with aerobic exercise. The stronger you are, the better you will be at any aerobic activity.  Weight training improves your body's muscle-to-fat ratio (you end up with less body fat and more muscle), which improves both your health and your fitness level.
Endurance exercise isn't, however, the best type of exercise to do if you want to make your muscles bigger. Bodybuilding. You can increase muscle size by doing resistance exercises. Resistance exercise involves using your muscles to move an extremely heavy load. This type of exercise forces your muscles to contract as hard as they can, which leads to an increase in the number of contractile filaments within your muscle cells.