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Make Connections Even though damaging your muscle tissues can be a good thing, you don’t want to injure your muscles in ways that could keep you from being able to continue your exercise program. A pulled muscle is something totally different from the kind

of tissue damage that makes you stronger. A muscle that’s been torn or strained can be extremely painful. Mild to moderate muscle pain is nor- mal and healthy—but extreme, severe pain isn’t. So start slow. Don’t push your muscles too hard at f irst. Build up gradually. Give yourself days off in between strenuous exercise or work on different muscle groups on alter- nate days. Always make sure to stretch and warm up before any strenuous exercise.

HOW EXERCISE CHANGES YOUR MUSCLES Depending on what kind of exercise you’re doing, your muscles could change in a couple of different ways. The muscles in your arms and legs have two kinds of muscle: fast-twitch muscles and slow-twitch muscles. Fast-twitch muscles are what help you perform short burst of activity, while slow-twitch are good for endurance exercise over a longer period of time. When you start an exercise program, you probably have about the same amount of both kinds of muscles. But if you start a plan that involves exercises like swimming, bicycling, or jogging, you’ll soon build up more slow-twitch muscles. This means that your muscles will be able to keep working for a longer period of time without getting tired. They won’t put the same oxygen demands on your heart and lungs. The opposite would happen if you focused your exercise program on something like weight lifting, where you needed your muscles to put out short bursts of power: you’d soon start to build up more fast-twitch muscles. Your muscles change, depending on the demands put upon them.

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Exercise for Physical & Mental Health