What is it?
In scientific terms, foam rolling is a form of self-myofascial release. In other words, rolling helps treat muscular immobility and pain. It does this by relaxing contracted muscles, improving blood and lymphatic circulation and stimulating the stretch reflex in muscles. The effects from rolling are similar to receiving a massage from another person.
Why should you do it?
Foam rolling has been scientifically shown to reduce post-exercise fatigue, therefore, providing quicker recovery from playing and training. It is important to note though that foam rolling has no effect performance. However, the reduction in fatigue can extend workout time and volume that can then lead to long-term performance enhancements. Remember, the main benefit of foam rolling is quicker recovery.
How do you do it?
Foam rollers are found in many different forms, some are soft, some have ridges, but all are used the same way. Foam rolling can be completed with a specially designed compacted foam roller sold in many sports shops. Alternatively, rolling can be completed with a PVC pipe. All types should give similar effects. To roll you want to apply pressure to the roller as you roll up and down on the roller. Muscle groups to target are calves, hamstrings, glutes, quads, IT band (outside of quad), groin, hip flexor (top of the quad), and back (lower and upper).
Here is a demonstration video of how to roll: https://www.youtube.com/watch?v=khC5J1lkC7s