Huberman – Stretching, Pain, Tumors and Yoga
By Kristine Kaoverii Weber | June 25, 2022
Stretching is an aspect of yoga, but to equate yoga with stretching is a common mistake and an ongoing problem for the yoga profession (including pop yoga culture’s obsession with stretchy hamstrings and “open hips”). Gratefully, neuroscientist Dr. Andrew Huberman understands this (to some extent) in his recent podcast on stretching and acknowledges that yoga has benefits that go beyond increasing range of motion:
“Practitioners of yoga don’t just learn movements, they learn how to control their nervous system in ways that really reshape their relationship to pain, to flexibility, and to the kinds of things that the neuromuscular system was designed to do.”
I’ve been listening to Huberman’s podcast since he started about a year and a half ago. He produces some fun, interesting episodes (okay, he can be redundant but I kinda like that about him – since repetition is how we learn). Anyway, I was excited last week when I saw his episode was about stretching and I listened to the whole 2 hours and 6 minutes – twice – in order to pull out some of the juiciest bits (you’re welcome).
Mechanisms of Stretching
As usual, Huberman starts with the basics – what’s going on with stretching at a neuromuscular level – if you want to review that, listen to the first 20 minutes or so (after the ads). An important point is that just about everyone needs some kind of stretching – because between the ages of 20 to 49 we lose about 10% of our flexibility every decade (and I’m assuming more after that, but his audience must be mainly millennials because he doesn’t clarify 😘).
What’s even more interesting to me are the benefits of stretching that go beyond increased range of motion, but we’ll get to that in a bit.
Huberman then discusses the different kinds of stretching (static, dynamic, ballistic, and PNF) and concludes from the literature (citing this article) that all stretching is good, but static stretching seems to be the most beneficial (and the least risky) for increasing limb range of motion. He recommends that you stay in a stretch for about 30 seconds, for an average of 3 sets, 5 times a week, to make changes in range.
This is different from what I’ve heard from various yoga trainers BTW – particularly the Yin yoga folks – so it would be interested to read critiques of this podcast from some of them.
But Huberman’s assessment doesn’t contradict how I was trained in the Viniyoga tradition – where there are typically several repetitions of a pose (in order to give the Golgi tendon organs a chance to figure out what’s going on and allow the stretch) and then a stay that is often in the 30 second range. BTW, I prefer the term “stay” rather than “hold” because it produces a less aggressive attitude toward practice and, as we’ll get to in a moment here, less aggressive stretches appear to be more beneficial.
The next question Huberman explores is how hard should you stretch? You may or may not know that Huberman is a serious gym rat, so this question is particularly important to him. And, need I say, the exercise world is rather biased towards more is better, feel the burn, no pain no gain, etc. thinking.
But I have to give the guy props here, the fact that he even considers this question is remarkable to me.
For me, thousands of hours of exploring slow, mindful movement in my own yoga mat laboratory revealed the same results as what he got from this study published in the Journal of Strength and Conditioning Research, which is that “very low intensity stretching,” meaning “effort that feels not painful and might feel easy and not straining” turns out to be more effective than moderate intensity stretching.
“I find these data incredibly interesting…If you are going to embark on a flexibility and stretching training program, you don’t need to push to the point of pain. In fact, it seems that even approaching the point of pain is going to be less effective than operating at this 30-40% intensity prior to reaching that pain threshold.”
Huberman has a hard time wrapping his mind around the why. He doesn’t buy the author’s commentary that it may have something important to do with how low intensity stretching (i.e. not painful stretching) prompts a parasympathetic response. Hmm. That seems really obvious to my armchair neuroscience mind, but I’ll just let that be.
Huberman and Yoga
After about an hour and 45 minutes of exploring stretching research, Huberman finally gets to yoga. He mentions that he’s not a yoga practitioner, but that he’s done some hot yoga and it was really hot in there. 🤣
Still, he’s so impressed by this study which showed that yoga practitioners have greater pain tolerance and more gray matter in the left insular cortex, that he begins to convince himself that there must be something useful going on. He says:
“If ever there was a practice one could embark on that would not only increase flexibility and limb ROM, but would also allow one to cultivate some improved mental functioning as it relates to pain tolerance and other features of stress management that no doubt wick out into other areas of life, it appears that yoga is a quite useful practice.”
Then he shifts and starts to talk about the benefits of stretching beyond range of motion.
I’m cheering again because he brings up research from Dr. Helene Langevin at the National Center for Complementary and Integrative Health (she’s one of my faves) about the health benefits mice enjoy from getting stretched.
If you want to watch Dr. Langevin talk about how she carefully stretched mice (and BTW, the mice liked it), watch this. She starts to get into it at about 13:40 mark. Not only is Dr. Langevin insanely brilliant, she’s also disarmingly adorable. Her study showed a 52 percent reduction in tumor growth in the mice that got stretched.
This study demonstrates that there is some correlation between stretching and a reduction in inflammation and increase in relaxation that helps the immune system combat tumor growth (at least in mice).
I definitely recommend listening to the whole podcast – if you have the time (and the band width). But I hope this synopsis has been helpful.
Yoga is not simply stretching, but stretching is an aspect of yoga practice. I love when neuroscientists start to explore the benefits of yoga and I’m glad Huberman was able to step outside his gym box to see that there may be other ways to approach stretching that improve health. Still, there are plenty of things about yoga that neuroscience cannot explain – and may never.
The yoga practitioner walks a path between science and mysticism – a journey that acknowledges the beauty of both analysis and experience, data and magic, the known and the unknown.