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17 September 2014
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All types of exercise involve using your muscles to generate movement. Regular exercise can increase muscle size, strength and endurance. But not all exercise produces the same effect.

Endurance exercise

Endurance exercises like running or cycling make your muscles stronger and less likely to get tired. This sort of exercise doesn't only benefit your skeletal muscles. It also:

  • Enlarges your heart so it can pump blood around your body more quickly
  • Increases the capacity of your lungs so you can breathe in more oxygen with each breath
  • Improves your digestion
  • Makes your metabolism more efficient
  • Strengthens your skeleton
  • Improves your coordination

Endurance exercise isn't, however, the best type of exercise to do if you want to make your muscles bigger.


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. This makes your muscle cells enlarge and, as a result, it makes your muscles bigger.

Endurance and resistance combined

Some forms of exercise offer the benefits of both endurance and resistance exercise. Swimming improves endurance, and as you have to push against water to move forward, it is a resistance exercise, too.

Energy is directed to your muscles during exercise

If you're doing intense exercise, other systems in your body focus their efforts on helping your muscles. Your heart beats more quickly so that it can pump more blood to your muscles, to provide them with more oxygen and nutrients. Your digestive system slows down so that it does not use up energy that your muscles need.

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