When your musckes aren't often used, your body quits supporting your muscles with energy, which causes them to atrophy (shrink). So the harder you work your muscles, the more your body appreciates them.
When muscles are exercised regularly they increase in size strength and endurance. When they are exercised vigorously they increase in size and strength rapidly due to enlargement of individual muscle cells. When muscles are not used they become weak and can waste away.
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When your musckes aren't often used, your body quits supporting your muscles with energy, which causes them to atrophy (shrink). So the harder you work your muscles, the more your body appreciates them.
When muscles are exercised regularly they increase in size strength and endurance. When they are exercised vigorously they increase in size and strength rapidly due to enlargement of individual muscle cells. When muscles are not used they become weak and can waste away.