If you are active in any way, you should be rolling out your muscles. The first time I tired it, it was like hell! So I stopped and didn't do it again for so many years!
When I begin to get into skipping and long distance running earlier this year I ended up really hurting my knees. To the point were I couldn't get up and down my stairs at work! I went to a physio and found out that my ITB and quads were tight. The ITB runs over two joints, it starts above your hip runs all the way down the outside of your thigh then crosses over your knee so if it gets too tight it can put strain on these joints giving you a sore lower back or a sore knee.
The physio began to massage out my thighs, I was in so much pain but I couldn't yell or slap her off me! I scrunched my face and squeezed my own hands as they began to sweat. I left with knees that felt better but with legs left bruised and painful to touch for days. My physio explained the need to look after my leg muscles if I wanted to keep up my running and skipping and gave me a run down on what I should be doing on a roller. I vowed that I would take this seriously not only to look after my knees but also to never have the experience a 'remedial' massage like that again!!
As the ITB is hard to stretch it's best to roller it. So I got myself a roller and began the pain of rolling out the side and front of my thighs. Again it was extremely painful, but this time I had not choice! With regular use it actually goes from pain to pleasure as your muscles begin to loosen up! I now love to roll out my legs and find that it's a good indicator for how tight my legs are - the more painful it is, the tighter they are.
My physio also taught me the best way to roll out your legs, don't do it in one big sweep back and forth but roll in sections of about 2 inches where you rock back and forth 10 times starting just above the knee then move to the next section up your leg and repeat. Once you get all the way to the top of your leg, go back down the same way. When doing the front of your legs (your quads) also do a set where you are continually lifting your feet up to you bum and back down as you roll. This means you are activating your quads as you roll them.
The more weight that you put on the roller the stronger it will be, so I suggest that when you start out to have one leg out in front of you to put your weight on when doing the side of your leg, as you progress you can move to having your legs stacked on top of each other and both feet off the ground.
The best time to roll is just before or just after any exercise that is using these muscles a lot (which ever feels best for you). Running, skipping and cycling/spin class are usually the prime culprits in tightening your quads and creating an imbalance in your legs. So if you are doing any of these, its time to get rolling!
The roller is not just for your legs, it's great anywhere on your body that you can roll!! I love to roll and stretch out my back and upper thoracic, my glutes, and my hip flexors.
You can get all different types of rollers. Some are completely made from foam. These are generally softer, while others are a hollow plastic tube with foam on outside. These are generally a lot harder.
I would recommend starting out with the softer foam rollers as they are a little more gentle on your muscles.
So next time you see the foam rollers at your gym, don't avoid them! Give it a go and start to see the benefits of keeping your muscles flexible and balanced as they become stronger.