Foam rollng, also known as self-myofascial release, helps maintain your soft tissues.

It is a good warm-up before strength training.

If it is too painful, use a softer ball.

Just roll 5 - 10 times so you don`t injure the soft tissues.

Here is a video on foam rolling for hamstrings.

One can foam roll many body parts and if you do not have a foam roller, you can use a ball (stability ball, tennis ball, basket ball or children`s playtime ball).

For some muscles a basket ball is too hard so I use a softer children`s playtime ball or stability ball for them).

Video source: http://www.youtube.com/watch?v
=a1NSa8magzM