Hamstring tears are very common soccer injuries. A study in Scandinavian Journal of Medicine & Science in Sports shows that preseason strength training helps to prevent injuries to these muscles in the back of the upper legs (Volume 13, Issue 4, 2003). Players from two of the best soccer teams in Sweden were divided into two groups. One group received specific hamstring training of 10 weeks of twice a week, using a special device to overload the hamstrings eccentrically. The trained group had less than one third the hamstring injuries of the untrained group, and also had greater improvement in hamstring strength and running speed.

The findings of this study should encourage preseason strength training for other muscle groups stressed in any sports. While stretching can make muscles longer to exert a greater torque on joints, it has not been shown to prevent injuries. Muscles are injured because the force on them is greater than their inherent strength, so they tear. Resistance training makes muscles stronger so that they can withstand greater forces and therefore helps to prevent injuries.

You can help to prevent injuries by stopping exercise when you feel pain and by not exercising intensely when your muscles feel heavy or sore.

Muscles are made up of millions of individual fibers. When you first contact a muscle, you use only one percent of the fibers. As you continue to exercise, you contract more fibers, which share the load, place less force on each fiber and help prevent injuries. So go slow before you go fast. When you feel pain in one muscle during exercise, that's a signal that it may be starting to tear and you should stop exercising. Every time that you exercise intensely, your muscles are damaged, causing them to feel sore on the next day. Exercising intensely when muscles feel sore injures them. So do not exercise intensely when muscle feel sore. It usually takes at least 48 hours for muscles to recover from hard exercise.