Why are some athletes more prone to hurting the Achilles tendon?
Tendons are made up of strong, fibrous tissue and their job is to connect muscle to bone. The Achilles tendon, located in the back of your leg, just above the heel, has a very big job. This tendon bears the body weight plus the weight and force of acceleration - often without any warm up.

The Achilles tendon can be hurt by suddenly starting up without adequate warming up to stretch the tendon, adding one too many stairs or climbs to your regular routine, running too fast too suddenly, or overuse. It can also be hurt by a trauma, such as being hit with an object.

The best way to prevent such an injury is by proper warming up and cooling down, and to be smart about exercising within your body's limits.