Updated: Dec 27, 2018
You're probably familiar with foam rollers. However, you may not be familiar with how they work or why they work. Getting clearer about the "how" and the "why" of foam rollers can help us understand more than foam rolling. It can help us understand how to make better training programs for ourselves and others.
Let's take a look at a specific study to get an overview of the major concepts we want to look at. The article I'll be referring to is called "Pain pressure threshold of a muscle tender spot increases following local and non-local rolling massage" by SJ Aboodarda, AJ Spence and Duane C. Button. You can take a look at the "Methods" section on your own, but the aim of the study was to "determine the acute effect of rolling massage on pressure pain threshold (PPT) in individuals with tender spots in their plantar flexor muscles" (Aboodarda, et. al., 1). You might be thinking 'Hey, now! This is geared toward plantar flexor muscles.' Rest assured, this will also apply to foam rolling muscles in general.
What were the results of the study?
They found that heavy massage/rolling to an area with a tender spot can provide an acute increase in pain threshold. Interestingly, a similar effect could be observed when heavy massage/foam rolling is done to the contralateral (think " the side opposite the tenderness") side. Since the increase in pain threshold was not a localized phenomena because it occurred from rolling on either side, then our CPM (central pain-modulatory system) may play the main role in mediation of perceived pain following these rolling/massage sessions.
CPM (conditioned pain modulation OR central pain-modulatory system) is also known as DNIC (diffuse noxious inhibitory controls). This is a pain modulatory pathway in our bodies. It occurs when one painful stimulus is reduced or inhibited by the introduction of another painful stimulus. In the article the tender plantar flexor muscle was one painful stimulus and the heavy massage/rolling was the introduced painful stimulus.
Noxious stimuli activate the endings of nociceptive C and A delta nerve fibers, which carry the signal to neurons in the dorsal horn of our spinal cord. The word "nociceptive" comes from the Latin word nocere: 'to harm or hurt.' The main goal of nociceptors is to respond to damage being done to the body by sending signals to the brain. DNIC refers to the mechanism by which specific neurons responsive to stimulation from one location of the body may be inhibited by noxious stimuli (such as heat, high pressure - foam rolling - or electric stimulation) applied to another, remote location in the body.
Why Should a Personal Trainer Care?
I'm sure there are more reasons than this, but here are a few:
Manual therapy is becoming popular in personal training. The problem is, we are not physical therapists. Personal trainers that are not schooled as physical therapists should not be doing manual therapy. It puts themselves and their clients at risk for either lawsuits or injuries or both. However, knowing that foam rolling (something your clients can do on their own) can reduce perceived pain levels and increase pain threshold in the short term gives you one way to manage pain without getting hands on.
The human body is an amazing thing. Just like in anything we do, pain toleration is built up slowly. Eventually, more stimulus will have to be applied in order to get the same effects. This is similar to lifting. You may get great results when you first start, but eventually that weight needs to be increased. By applying this principle to your clients' foam rolling routine, you can make sure to always be increasing stimuli to the nervous system so they're constantly making progress. In fact, most strength gains come from the nervous system as well.
In tandem with 2 above, foam rolling after a hard workout can reduce soreness that same day and the day after. The response is acute, so foam rolling may need to be done later that night or the next morning as well. This allows the more intense athletes out there to still work hard the next day without that lingering soreness. This is also a great way to reduce soreness in clients when they have to work that 8 hours shift sitting at their desk the next day.
Finally, we can truly say that pain is gain...kind of. The phrase is more like "pain inhibits pain." We have to distinguish between sources of pain and location of pain. So really, pain is gain in only one sense.