Stretching- It’s Gotten More Complex Since High School

Cate Airoldi BS, CPT, LMT

Stretching is often one of the things we runners enjoy least. I certainly fall into that category. We face a constant conundrum with our bodies, a need for the diametric opposites of stability and mobility. With limited time (and maybe limited motivation?) stretching often falls into last place on the spectrum of self-care. But, stretching isn’t what it used to be. Theories around what type of stretching is most efficacious and when to stretch have changed dramatically in the last decade. Different modalities (or types) of stretching are also plentiful.

In this blog we’ll investigate passive and active stretching, foam rolling, cupping, IASTM (instrument assisted soft tissue mobilization), when might be best to stretch, and when you may want to hold off. One thing I encourage you to consider as you read further is the possibility that creating increased mobility in a joint and it’s adjacent tissue (rather than less dynamic static muscular stretch) might contribute more meaningfully to joint health^1,5,7,11. Increasing mobility at a joint involves addressing not only the joint and capsule itself, but the supportive ligaments, fascia, and tendons around the joint as well as muscles that move the joint¹⁰. Traditional stretching in the sense most of us think of might create a temporary lengthening of the muscle being targeted but does not usually explicitly target joint ROM (range of motion). So, I will use the term ‘stretching’ throughout this article, but as you read on you’ll see that some stretching is limited in scope and provides only short-term results¹¹, whereas some of the newer techniques are focused on increasing tissue mobility and joint ROM simultaneously.

Do you remember when, 10, 20, or 40 years ago in gym class the teacher hollered at everyone to ‘stretch it out-limber up!’ before your fierce game of dodgeball? At which point everyone in the class proceeded to half-heartedly grab an ankle and hold a static quad stretch for a few seconds, or maybe bounced on the edge of a stair to ‘loosen up’ their calves. Ok, so even if your gym class was a little more progressive than that of my rural upbringing, things have undoubtedly changed on the stretching front since any of you reading this were last in gym class.

Modalities concerning stretching have expanded to include theories for what type of stretching is best for which sports, when you should stretch, what tools can aid in stretching, and if stretching is even really beneficial in the first place. I do want to say at the outset here that some folks swear by their particular stretching routine or yoga practice, and if it makes you feel better then absolutely keep doing it. This is more for the runners like me who don’t particularly enjoy stretching and are often unsure about how to get the most benefit in the least amount of time.

The old-school type of stretching that we’re probably all familiar with (like that lackluster gym class quad stretch) is called static stretching. As the name would indicate, no movement is involved, and a muscle group is held in an elongated position for a length of time in the hopes that the soft tissue will release by degrees leaving you with a greater range of motion (ROM)^1,6. A big issue-and there are several- with this type of stretching is that people rarely hold the stretch long enough for the necessary physiologic response to kick in that actually allows your tissues to relax. Also, a lot of people may start static stretching cold, and there is some real truth to the old wisdom behind warming up your body before you stretch it. Think of your muscles like rubber bands; if you stick them in the fridge overnight or leave them in one position for an extended time period, they’ll have trouble adapting to a new shape. The same generally applies to your muscles, albeit it on a much more complex level. It is also worth mentioning that there’ve been some preliminary studies¹¹ showing that stretched tissue returns back to its pre-stretched state within a much shorter timeframe than previously thought, insinuating that the effects from static stretching in particular can be short lived and measured on the order of minutes rather than hours or days. Additionally, there have been some interesting research articles^7,11,13 within the past decade pointing to the fact that athletes from the recreational to elite level would do better to focus on strength building rather than stretching, and that stretching can even produce a temporary decrease in performance. If you’ve read any of my blog posts up to this point, you’ll know I always find a way to sneak in some science, and this is where some muscle physiology is needed to clarify further.

Muscles and tendons (which attach muscles to bones) have built in mechanisms to maintain daily posture plus all the minute adjustments it takes to achieve bipedalism, and to prevent injury as much as is humanly possible. These features, called the ‘Myotatic reflex’ and the ‘Golgi Tendon reflex’ are constantly in use without our even being aware of it. For example: if you slip on an icy patch of sidewalk and your foot begins to skate away from you, these reflexes are enacted before you’re even cognizant of the fact you’ve slipped. The Myotactic reflex initiates within the actual belly of a muscle and causes a muscle to contract when a stretching force is being exerted on it^4,10. This can be seen as a muscle’s attempt to counteract imminent injury from undue excessive stretch or force. The Golgi Tendon reflex happens in structures called Golgi Tendon Organs (GTOs) located in the tendons of the body. It responds to excessive force by inhibiting muscle action via the tendon it’s attached to-it’s essentially a forced relaxation from outside of the muscle belly. For example, if the GTOs in the bicep tendon sensed a dangerous amount of stress being put on the bicep tendon, they would signal the bicep muscle to relax rather than contract under dangerous stress^4,10. Obviously, these protective reflexes can be overridden and are not perfect. Sudden, external factors like falls or blows to the body fully illustrate this imperfection. But on the whole it’s a pretty amazing protective system that leaves us in much better shape than we would otherwise be without it.

Ok, so why have I been going on about reflexes with science-y sounding names if this is an article about stretching? It’s because those protective mechanisms kick in with most types of traditional stretching, and a certain amount of time needs to elapse for these systems to be overridden. The nervous system will eventually catch on that the stretch being exerted on a muscle and tendon is intentional and not accidental, and then will allow for those soft tissues to relax. If you release a stretch before that recognition from the nervous system has happened, you’ll have done virtually nothing of consequence to elongate the muscle because the reflexes we just discussed will still be active. There is some debate about what the precise magic timeframe to hold a stretch is, but it’s safe to say that at the low end most agree that a static stretch needs to be held for at least 30-45 seconds to override the Myotactic and GT reflexes^3,11.

There are a two types of active stretches I use almost daily because they’re time effective and yield tangible results. The first is called Active Isolated Stretching (AIS). AIS is super-short stretching that occurs in two second intervals. The reason this modality employs such a short timeframe goes back to that reflex physiology we discussed earlier. There is actually a short window of 2 seconds before the Myotactic and GT reflexes truly kick in, and AIS capitalizes off of this³. By going into the stretch for a count of two, you can slip under the reflex barrier and achieve a muscle and tendon stretch without triggering the protective contraction or inhibition reflexes. AIS is not bouncing or ballistic stretching, which can be exceedingly dangerous. It is a controlled, intentional movement into a stretched position for two seconds with a rest interval of two seconds. I often use this mid-run or race because it takes very little time, and when done correctly doesn’t risk tissue overstretching or decreased force output from the muscle.

Muscle Energy Technique (MET) uses the principle of reciprocal inhibition to stretch you out. This is another active modality, and you’ll need a buddy or therapist (like a Manual or Physical Therapist) to help you out. With an MET you’ll be asked to isometrically contract one group of muscles against a barrier which will cause the opposing musculature to relax². The reason this works is that when a muscle on one side of a joint contracts the muscles on the opposing side must necessarily relax, this is reciprocal inhibition in its simplest form. For example, if you were going to stretch the hamstrings using an MET you’d do the following: lie in a supine position with the stretch leg raised in the air perpendicular to the floor (as close to 90° as you can manage without causing initial notable stretch). Next, your raised leg would push downward towards the floor (activating the hamstrings) against the barrier provided, this will probably be the therapist’s shoulder or hand, for 5-10 seconds. After this you’ll relax whilst the therapist gently pushes you a little further into the hamstring stretch. Typically 3-5 repetitions of MET are applied to one area. This modality is great for improving ROM at virtually all joints in the body, and I use this post long run and on rest days to delay the onset of joint stiffness that accompanies particularly long training sessions.

The next few modalities we’ll go over next are probably not what most people might call to mind when I say ‘stretching,’ but they can be considered under the same umbrella. The goal of active and passive stretching is to mobilize tissues, increase joint ROM, and decrease musculotendinous pain. The following all share that same goal but achieve it via more non-traditional means. These therapies can also all be active or passive depending on your end goal.

Foam rolling is pretty familiar to most runners and needs very little further explanation. The thing to remember with foam rolling is that the same principle of holding a tender spot for a minimum of 30 seconds to elicit muscle relaxation applies here. While you can definitely actively roll back and forth as the name implies, if you hit an adhesion or trigger point (notably sore and immobile fascia and/or muscle) you’ll need to hold the spot for at least 30 seconds to begin the tissue lengthening proccess.
Cupping Therapy is a form of manual therapy that uses small cups which can be plastic, glass, or rubber to suction the skin underneath into the cup. (A quick note: in this post I’m referring to Fixed Dry cupping; there are a multitude of cupping types). Cups are usually left on for 3-5 minutes in the target area. The after-effect of cupping can often be seen for hours if not days in the form of round, red marks that look like bruises on the skin. The thinking is that these red areas are where the suction from the cup has moved metabolic wastes from the tissues underneath up to the subcutaneous layer¹². Cupping is relatively new to the Western world but has been around in parts of Asia for thousands of years. This is a therapy that has some controversy surrounding it as to whether or not it really is efficacious, and the decision to pursue cupping needs to be made on an individual basis with consideration to any contraindications (risk factors) you might have for receiving this therapy. Also, cupping should only be done by a practitioner with the training to perform this modality. Oftentimes you’ll see high-level athletes with cupping marks (remember Michael Phelps and Simone Biles at the 2016 Olympics?). Seeing these high level athletes with cupping marks indicates what many see as a great side benefit to cupping- it doesn’t interfere with your competitive ability, and some would swear to the fact that it helps recovery time by leaps and bounds. Again, I think this is an area everyone needs to decide on for themselves, but in full disclosure I use cupping fairly frequently after hard efforts like hill repeats or heavy strength training for XC skiing.
IASTM or instrument assisted soft tissue mobilization⁵ goes by a few other names too. Graston Technique, Gua Sha, and Scraping are all terms I’ve encountered other therapists using with frequency when refencing the same modality. The term ‘Scaping’ probably provides the best idea of what this looks and feels like. The therapist performing IASTM will use a metal or stone tool (typically curved and with a beveled edge) to scrape along your skin with the ostensible goal of improving blood flow and elongating the fascia⁵. Just like cupping, this will often leave visible red marks on the skin that resemble road rash. It’s also another new-ish arrival to the Western world and comes with the same controversy as to whether or not it’s pseudoscience or if it does actually convey tangible benefit. The same cautions apply here as well in that you’ll need to find a qualified therapist to perform this and determine if you have any risk factors that would prohibit you from getting IASTM.

There are a plethora of other stretching/tissue mobilization techniques beyond what I’ve covered in this post. The general scientific consensus is that active and passive stretching, when done correctly, probably conveys some benefit in the short term, will likely mitigate injury risk if you stretch on a long-term regular basis, and will probably not have deleterious effects on your musculature¹¹. Frustratingly vague and non-committal, right? The main take-away here is that there are a lot of ways to solve a problem, and it will take some research and experimentation on your part to determine which stretching regimen is best for you. It’s also worth noting that there are times that are definitely not appropriate to stretch or at least stretch aggressively. I think it’s fairly obvious to most that immediately following some sort of tissue trauma (like a sprain or fracture) stretching the inflamed and damaged tissue is not a good idea. Jumping straight out of bed before your soft tissue has warmed up and your circulatory system has adapted to being upright is also not an ideal time to stretch aggressively. Consider active stretching like AIS or, if you can manage it, an MET while you’re mid-activity. If you have recent joint injury, arthritis, osteopenia or osteoporosis you should definitely consult with your physician before you embark on a new self-care plan and use extreme caution when foam rolling or receiving treatment near your affected joints.

The last morsel of food for thought is what I mentioned at the beginning: achieving that elusive balance between stability (ie: being strong) and mobility (ie: being bendy). Every athlete needs to consider what their objective is. Gymnasts have what might be the trickiest task of all sports with this balance- being super strong and impossibly flexible at the same time. Runners obviously do not need that level of joint mobility and there are some that argue stretching should not be the focus of performance minded athletes, and stability outranks mobility^7,11,13. The thinking is that a strong body is protective of joints and soft tissue, and therefore conveys more durability to the runner. The other side of the coin is that if you’re super strong but lack mobility, your soft tissue will be so constantly hypertonic (tight) it’ll always be on the verge of tearing, straining, or spraining.

To tread lightly into this debate, I side more with the category of favoring stability over mobility. What this means in practice is that, given limited time, I’m much more likely to use those minutes for a couple quick strength exercises than stretches. This is not to say that I never stretch, because I do, and I often feel better afterwards. But, from my personal experience I’ve felt more benefit with prioritizing stability than I would if I were a stretching devotée pursuing superhuman feats of flexibility.

References:

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Kukkonen, P. T. “Scientific Basis of Active Isolated Stretching: A Review.” Journal of Exercise Physiology Online. 2019. 22 (2): 58-70. Web.

Konoza, E. ATC. “The Role of Muscle Proprioceptors in Proprioceptive Neuromuscular Facilitation (PNF) Stretching.” MUSC Health Sports Medicine. 1 October, 2018. Web.

Looney, B., et al. “Graston Instrument Soft Tissue Mobilization and Home Stretching for the Management of Plantar Heel Pain: A Case Series.” Journal of manipulative and physiological therapeutics. 2011. 34 (2):138-42. Web.

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Rowlett, C.A., et al. “Efficacy of Instrument-Assisted Soft Tissue Mobilization in Comparison to Gastrocnemius-Soleus Stretching for Dorsiflexion Range of Motion: A Randomized Controlled Trial.” Journal of Bodywork and Movement Therapies. 2019. 23

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Schünke, M., E. Schulte, and U. Schumacher. Thieme Atlas of Anatomy. Edited by L. Ross, and E. Lamperti. Thieme Medical, Stuttgart, 2006.

Shrier, I. “Chapter 3: Does Stretching Help Prevent Injuries?” Evidence Based Sports Medicine 2^nd Edition, edited by MacAuley, D., and Best, T.M. Blackwell Publishing, 2007, pp. 36-58.

Tamer, S. A., and AlSanad, S. “Cupping Therapy: An Overview from a Modern Medicine Perspective.” Journal of Acupuncture and Meridian Studies. 2018. 11 (3):83-87. Web.

Waryasz, G.R. et al. “Personal Trainer Demographics, Current Practice Trends and Common Trainee Injuries.” Orthopedic reviews. 2016. 8 (3): 6600. Web.