Why Foam Roll?
Foam rolling has grown in popularity for many reasons, one of the biggest of which is the inexpensive accessibility to self-maintenance. Foam rolling is a form of self-myofascial release, a modality that is supposed to release tension in muscle and connective tissue in order to relieve pain and mobility restrictions. While I won’t dispute the correlation between this technique (and other myofascial release techniques) and reductions in pain and improvements in mobility, the real question is why is there a correlation? If we can better understand the why behind this modality, then we can better apply it to situations that may benefit from it, instead of prematurely assigning it to every mobility restriction and soft tissue ailment that we face.
First, we must address why we do not foam roll. We do not foam roll in order to change the composition of the connective or muscle tissue of the body in any physical or mechanical way. Most research looks at the effects of foam rolling on joint range of motion, flexibility, or change in performance, not physical tissue parameters. There are also studies looking at the effect on physiologic factors, such as arterial function, inflammatory markers, and nervous system response. If the amount of pressure used through foam rolling actually did physically change macro tissue composition within the small timeframe we use if for, then every time we stand up from sitting for any length of time, we would end up with flat asses. The body just isn’t that malleable; it is resilient and likes to maintain homeostasis, which includes the ability of body tissues to maintain shape after being in a certain position for any length of time.
As noted before, there IS evidence that foam rolling has been shown to correlate to improved range of motion and flexibility. But how? It’s not by breaking up adhesions or knots in the muscle fibers or by physically lengthening the components of muscle tissue. When you apply a stimulus to the skin, be it pressure, light touch, vibration, cold, hot, etc., that input is interpreted by the brain to give a perception, and then a response. Sometimes the perception is that the input is harmful, other times not. In many cases, you can be desensitized to this stimulus if it is performed enough in either an acute or chronic dosage. For example, when you first get into a hot tub, the water temperature is high and may feel too hot to tolerate. After you have been in the water for 10 minutes, it no longer feels as hot and is more tolerable. The temperature of the water has not changed, but your perception of it has. This change comes from the nervous system, and this may be what is influenced with foam rolling, and what gives rise to the changes we see.
Many types of myofascial release have been shown to increase parasympathetic nervous system activity, which includes the body’s ability to recover and come back to homeostatic levels, or the “rest and digest” functions. If different myofascial release techniques are correlated to a change in this activity (including foam rolling and trigger point release therapy, just to name two), then we can induce that a mechanism by which these techniques work is through influencing the nervous system in order to change the way the brain perceives tissues. This stimulus to the nervous system can help with reduction of pain/sensitivity and fatigue, therefore aiding in recovery and increasing the available ROM before a stretch or other