By Bernie Clark
March 1, 2026
Feeling stressed out? Too much stress in your life? Need to reduce your stress levels? It seems obvious that stress is a bad thing. Just think of the word “distress.” Who wants to be in distress? Maybe the fault is not in being stressed, but in having too much stress or being stressed too often. There is another word that few people know: “eustress.” 1 Eustress is the appropriate amount of stress needed for growth, strength, and resilience. All living organisms need optimal levels of stress to survive and thrive. The challenge we face is knowing when enough is enough, and avoiding too little stress when some stress is needed.
Stress in the yoga class – Negative synonyms
I once had tea with a senior yoga teacher who was visiting Vancouver for a weekend workshop. We were discussing yin yoga and his distaste for it. I was surprised and asked why he was against the practice. He pointed out that in many yin yoga postures students were collapsing into their joints. For example, he said that in Cobra (which in yin yoga is called Sphinx), students were compressing their lower back.
“Yes,” I admitted, “in Sphinx pose we deliberately compress the lumbar spine.”
He was shocked and repeated my words: “Yes, you compress the spine!”
I agreed once more: “Yes, we compress the spine!”
We looked at each other with mouths open, silently questioning each other’s sanity.
What was going on? He clearly felt that stressing the bones and joints was an unhealthy thing to do. I have heard similar fears from yoga teachers who believe that stretching ligaments is also unhealthy. Frightful words are often used to describe stress in a yoga practice: dumping, collapsing, crunching, jamming, clenching, slumping, locking, impingement. Phrases include “hanging out in the ligaments.” These do sound scary. What student wants to crunch their lower back? But despite the fear, are these stresses really harmful?
NASA Stresses their Astronauts
NASA Astronaut Joe Acaba stresses the importance of exercising in orbit, and dives into the science behind what happens to bones and muscles in microgravity.
I explained that all tissues require an appropriate amount of stress to regain and maintain optimal health. He challenged me on that assertion, so I pointed out that the U.S. space agency, NASA, is very concerned about the health of astronauts because once they are in orbit, gravity no longer stresses their bones, joints, muscles, and fascia in the usual way. Over weeks and months in space, muscles and bones atrophy. Without stress, tissues weaken. We need stress.
My friend was dubious and asked me to send him evidence of NASA’s findings, which I did.2
I have to admit that the amount of compression on the lumbar spine during Sphinx pose is too low to be osteogenic (meaning it is not enough to stimulate measurable bone growth). However, this does not mean it is not valuable. The body needs stimulus in all tissues to avoid atrophy and maintain functionality. Our bones and cartilage require compressive stresses. Our ligaments, muscles, and tendons require tensile stresses. Avoiding stress is not the path to optimal health.
Hormesis and Antifragility
There are two terms that are useful for yoga teachers to understand: hormesis and antifragility. Hormesis refers to the ability of a tissue, or the whole body, to adapt to appropriate levels of stress. Too little stress and nothing happens. Too much stress and the body breaks down. The key is dosage. Within an appropriate range, tensile and compressive stresses act as constructive stimuli, encouraging maintenance and, in some cases, modest strengthening of the tissues involved.
Antifragility goes a step further. 3 If fragile means easily damaged by stress, and robust means merely resistant to stress, antifragile describes a system that improves because of stress.4 A well-rounded yoga practice exposes the body to varied planes of movement, different ranges of motion, alternating tension and compression, balance challenges, and breath regulation. Over time, this variability builds adaptability: joints tolerate more positions, muscles coordinate more efficiently, and the nervous system recovers more quickly. The body does not simply survive stress; it becomes more capable because it has experienced it.
Medical science has long recognized that living tissues require mechanical load to maintain their integrity. In the nineteenth century, Julius Wolff observed that bone remodels according to the stresses placed upon it, adapting its internal architecture to habitual strain. Around the same time, Henry Davis proposed that soft tissues such as ligaments and tendons also remodel in response to tension.5 These principles reflect a simple biological reality: tissues deprived of stress weaken. Prolonged bed rest, immobilization, or microgravity leads to bone loss, muscle atrophy, and connective tissue deconditioning. While rest is sometimes necessary in acute injury, the complete removal of mechanical stress is rarely the ideal long-term prescription; appropriate, progressive stress is what restores and preserves tissue health.
How to tell when it is too much or not enough?
Admittedly, you can have too much of a good thing. Again, the dose is what makes the poison and the medicine. No stress is not good. Too much stress is not good either. But just because you can do too much does not mean we should do nothing. Each student’s challenge is to determine what level of stress is appropriate for their health today. The teacher is a guide, but this is one task that cannot be delegated. Students must take final responsibility for ensuring the practice fits their body.
How do you know when you are doing too much? Pay attention. A teacher cannot tell by looking at a student what is happening inside. The student has to notice what sensations are arising while in the pose, when coming out of the pose, and even over the next day or two. If pain or dysfunction arises, the practice needs to be modified. Please forget the erroneous adage “no pain, no gain.”6 Pain is a very important signal that should not be ignored if your goal is optimal health.
What do you feel when you do Sphinx pose? Instead of worrying that you may be “collapsing” into your lower back, what are the actual sensations there? Does it hurt? Is it truly uncomfortable? Are there sensations that are sharp, burning, stabbing, electrical, or tingling? Those sensations we do not want. Or are the sensations dull, achy, pressure-like, squishy, stretchy, or tugging? Those are the kinds of sensations we are often seeking.
Positive Synonyms for Stress
If the word stress feels harsh, choose another word. Call it load. Call it challenge. Call it demand, stimulus, tension, compression or simply exercise. Go back over this article and every time you see the word “stress,” read the word “load” instead. Does that change your perception? The language matters because language shapes perception.7 When we describe some sensations as collapsing, crunching, or jamming, we teach fear. When we speak of appropriate load and intelligent demand, we teach discernment.
Stress is not the villain. Uncalibrated stress is. The body requires mechanical input to remain strong and adaptable. Too little breeds fragility. Too much breeds injury. Between those lies growth. Whatever word you choose, do not avoid the stimulus entirely. Learn to apply stress wisely.
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Footnotes:
1 According to Wikipedia, “The word [eustress] was introduced by endocrinologist Hans Selye (1907–1982) in 1976; he combined the Greek prefix eu, meaning “good”, and the English word stress, to give the literal meaning “good stress”.”
2 NASA found that in microgravity, weight-bearing bones lose density and muscles weaken because they no longer work against gravity, with bone density dropping about 1 % per month if countermeasures aren’t used. See https://www.nasa.gov/missions/station/iss-research/counteracting-bone-and-muscle-loss-in-microgravity.
3 Antifragility: a property of systems that gain from disorder, volatility, variability, and stressors, becoming stronger or more capable when exposed to manageable challenge rather than merely resisting it. See Nassim Nicholas Taleb, Antifragile: Things That Gain from Disorder (New York: Random House, 2012).
4 To learn more about antifragility, read Are Yoga Teachers Making Us Fragile?
5 Rather than a rigid “law,” bone adaptation resembles a control system with thresholds: below a certain strain level bone is resorbed, within a maintenance zone bone mass is stable, and above a higher threshold bone formation is stimulated. See Ruff C, Holt B, Trinkaus E. Who’s afraid of the big bad Wolff?: “Wolff’s law” and bone functional adaptation. Am J Phys Anthropol. 2006 Apr;129(4):484-98. doi: 10.1002/ajpa.20371. PMID: 16425178.
6 Many athletes, dancers and gymnasts will ignore this advice, but their goals are not optimal health but, rather, maximum performance. That’s okay—it is their choice, but they should be conscious that they may be making a trade-off here. They may be exchanging long term health for present day performance.
7 Stress is a problematic term not just in the yoga world. Even psychologists have concerns over using it. See Burton RF, Hinton JW. Up the Tower of Psychobabel: does lexical anarchy impede research into ‘psychological stress’? Med Hypotheses. 2010 Apr;74(4):644-8. doi: 10.1016/j.mehy.2009.10.043. Epub 2009 Nov 25. PMID: 19932940.