Weegy: What Causes Muscle Growth?
In order for muscles to grow, three things are required:
1. Stimulus - exercise is needed to make the muscles work, use energy and cause microscopic damage to the fibers.
2. [ Nutrition - after intense exercise the muscles need to replenish their stores of fuel.
3. Rest - it is during the rest or recovery phase that the muscles repair the microscopic damage and grow. ]
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