Foam rolling or self-myofascial release (SMR) is something that’s been around since the late 80’s and over the last decade has continued to grow in popularity. You see it being used everywhere, from personal trainers to physical therapists, and of course every Crossfitter that ever existed. It’s a popular modality because it’s something you can do at home and tends to feel pretty good after enduring some of the discomfort that may come with it. SMR is so popular that a long with fame, comes the bogus claims. I’m here to tell you exactly what we think foam rolling is, what it does, and what it doesn’t do. In order to do this we need to start with some basics.
What the hell is fascia?
Let’s make this as simple as we can, but understand, it isn’t. Fascia is connective tissue in our body, made up mostly of collagen and elastin, connecting virtually everything together with arguably other roles. When you here MYOfascia, Myo (muscle), you can think fascia that wraps around a muscle. Fascia is hydrophilic and is filled with neurological sensory receptors. In fact, it is the largest sensory organ in the body. It’s comprised largely of free nerve endings that can function as mechanoreceptors or detect pain, Golgi receptors, Pacini corpuscles, interstitial receptors, and Ruffini nerve endings. All of these receptors play a role in SMR but Ruffini nerve endings and interstitial receptors are the most interesting. These Italian receptors (joke) detect and respond to sustained pressure as well as tangential stretches. Ruffini nerve endings are interesting because their response to activation creates a down regulation in the sympathetic nervous system with slow, sustained pressure.
Much Science…The Sympathetic Nervous System and Myofibroblasts
The sympathetic nervous system is part of the peripheral nervous system, more specifically the autonomic system. The sympathetic system is not under conscious control and is your “fight or flight” response. It reacts to stressful/threatening situations to shunt blood from certain organs and increases blood flow to other, more important organs, which are needed to create an appropriate response. This system can be triggered by simple threats such as stressful thoughts, emotions, a stressful work environment, really anything that the body may interpret as “danger”. Once a threat is detected, this system will release catecholamines, epinephrine and norepinephrine to accomplish its goal. This response also happens to release a cytokine called TGF Beta-1 creating a small immune response but also stimulating… you guessed it, Myofibroblasts. Lets talk about these guys for a second.
Myofibroblasts are cells found in fascia and are in-between a fibroblast (cell that creates structural support to the body) and a smooth muscle cell (found in the end of an autonomic/sympathetic motor nerve). These cells have been found to provide a relatively important role in fascia, creating active contractions within the tissue to increase stiffness. Technically, they do not respond directly to sympathetic control but indirectly through the sympathetic release of TGF Beta-1 mentioned previously. So, as someone is stressed or threatened, the sympathetic system ramps up, and creates a relative stiffness to protect the body, priming it for movement in order to find “safety”.
Oooh, Aaaah, I feel much better… less stiff… looser! As you foam roll you will be putting slow sustained pressure under the tissue you are rolling that signals those Ruffini and interstitial nerve endings. The Ruffini nerve endings will down regulate the sympathetic nervous system (fight or flight), decreasing the amount of TGF Beta-1, and allow those myofibroblasts to relax, thus, making you less “stiff”. This decrease in stiffness transiently increases the range of motion that the rolled muscle may restrict. For example, if you have determined that you have trouble squatting because you have a loss in ankle dorsiflexion (bending the ankle up) then you can foam roll the calf musculature to improve dorsiflexion. Most calf musculature will perform plantarflexion (pointing the toe/bending ankle down) so by decreasing the stiffness here may provide you with increased ankle dorsiflexion and improvement in squat depth.
What is Happening?
A relatively recent systematic review on foam rolling by Cheatham et al. (2015) attempted to look at all of the research to determine the relevance of foam rolling on joint range of motion, muscle recovery, and muscular performance. What they found was that foam rolling helped increase joint range of motion but as stated earlier, the effect was transient. Transient, meaning, that the effects wore off or returned to a previous state after about 10-15 minutes post SMR. Their finding suggest that SMR using a foam roll for thirty seconds to one minute, 2-5 times, or roller massager for five seconds to two minutes, 2-5 times, may be beneficial for enhancing joint flexibility as a pre-exercise warm-up and cool down.
They also tried to determine if foam rolling was worth the time for decreasing soreness or DOMS (delayed onset muscle soreness) that comes with exercise, more specifically higher intensity exercise. What they found was that foam rolling and roller massage after high intensity exercise does attenuate decrements in lower extremity muscle performance and reduces perceived pain in subjects with a post exercise intervention period ranging from 10 to 20 minutes. Continued foam rolling (20 minutes per day) over 3 days may further decrease a patient’s pain level and using a roller massager for 10 minutes may reduce pain up to 30 minutes.
What isn’t Happening….
According this same systematic review, Cheatham et al. (2015) determined that foam rolling does not actually enhance any muscle performance. They measured pre and post broad jumps, isometric strength, vertical jump height and power, and a timed shuttle run. They determined that there was no statistically significant change in performance based on those outcome measures but they did find that participants experienced a perception of less fatigue.
A good one I hear a lot is that people are foam rolling to break up scar tissue. Lets make one thing very clear… You are not breaking up scar tissue! Ask any surgeon and I am sure they will tell you that at times they have difficulty breaking up true scar tissue. THEY USE SHARP OBJECTS!!! So, do you really think you’re going to able to do so by rolling on the ground?
Last but not least, you are not making you tissues longer and you cannot stretch out your IT band. Chaudhry et al. in 2008 proposed a three-dimensional mathematical model for fascial deformation. They found that in the case of fascia lata (TFL), a predicted normal load of 9075 N (925 kg) and a tangential force of 4515 N (460 kg) are needed to produce even 1% compression and 1% shear. Such forces are far beyond the physiologic range of manual therapy. Putting these numbers into perspective, it’s like taking your TFL and hanging both a cow and a pig from it, only have that tissue stretch by 1%. Yea… So, basically, your hands are not going to be able to put the weight two domestic farm animals into someone’s tissue. Also, when it comes to making your muscles longer, it can be done, but not by foam rolling or your normal stretching routine. Making your muscles actually longer means that one must add sarcomeres (muscle cell) to it, which is achieved by either splinting yourself in a seriously stretched and uncomfortable position for a long period of time, or through eccentric exercise.
- There are other proposed mechanisms as to why SMR works but it most likely activates neurological receptors in skin, fascia, and muscle to produce the effects observed.
- SMR helps increase joint range of motion in the short term when performed for 30 seconds to 1 minute 2-5 times at a moderate pace (think 1 inch per second)
- SMR decreases the effects of DOMS when performed for 20 minutes post strenuous exercise
- SMR does not increase muscle or fascia length
- SMR does not improve muscle performance or output
- SMR does not break up scar tissue
- We still do not know 100% why it works…but it works
Hope this helped give a slightly more rational perspective on foam rolling but again it’s important to understand that a lot of proposed mechanisms are still being studied. All in all, SMR is useful but don’t go crazy making your entire gym or rehab session about it.