Why is swimming one of the best ways of developing physical fitness?

Because it is the only sport in which you use basically every muscle in your body. With football, Basketball, soccer, etc. you mainly use your legs for running or jumping, or your arms for catching or shooting, but with swimming, every movement counts, from you head position, to the spaces between your fingers. It takes a lot of strength and skills to efficiently propel yourself forward through water at the speeds swimmers do

Competitive swimming for 12 years (: