Q: I was in a yoga class doing downward dog and since my hamstrings felt tight I bent my knees and kept my heels away from the floor. The instructor came to me and told me to lower my heels to the floor. I told him I was keeping my knees bent because my legs felt too tight and he told me I needed to try and push my limits. Should I push myself to stretch harder when I am feeling tight?
A: You were right to bend your knees and stay in your comfort zone. This is a scenario that happens all too often in many yoga classes and although instructors should know better, many offer this kind of risky advice to their students. The motto of these instructors is that yoga is there for us to ‘push our limits’. They tell students that they cannot advance their practice unless they are willing to ‘push their limits’.
Let’s just explore the science of this ‘push the limits’ thinking. Physiological limits are there for a reason and that reason is the safe and proper function of the human body. In many poses in yoga we will create a pose that will cause our muscles to lengthen. There is a preset muscle length that our body will naturally allow. This muscle length is a factor of our typical body positions. In other words, if we hold postures that shorten our muscles the preset muscle length will be set to ‘short’. Conversely if we hold our body in postures that lengthen our muscles the preset muscle length will be set to ‘long’. The typical muscle length is not something that can be changed dramatically in a short period of time. Our muscles are designed to lengthen about 20% greater than their typical resting lengths. 20 percent is not a very large amount of change to a muscle that is typically held in a short posture.
When we are in a stretch and reach the end of the muscles comfortable length, in other words we have gone beyond the typical length and are now approaching the 20 percent greater length, we will feel an increase of sensation in the stretching muscle. In a properly held stretch the sensation is mild and pleasant. However, if we persist in stretching the muscle further the sensation will begin to increase. This increased sensation is the natural protective reaction of our body trying to prevent harm to the muscle by contracting the very muscle we are trying to stretch.
Inside our muscles are some very special receptors that constantly monitor the length of our muscles. When the muscle is lengthened past the 20 percent mark, these receptors go off and the muscle begins to resist the stretch. If we did not have these receptors to protect us then we could possibly pull our muscles apart from stretching too far. The building sensation in a stretching muscle is a warning for us to stop stretching.
No doubt we have all felt the sensation of a strong stretch. A strong stretch sensation is to be avoided. A stretch sensation that is constantly increasing is to be avoided. Not only do we risk damaging the muscle fibers from overstretching, we condition the muscles to resist the stretch. Our nervous system has a predictable response to pain and that is a drawing inward and cringing response. Trying to force a muscle into a stretch is a recipe for disaster and can result in muscle strains and shortened muscles as the body increases its desire to protect and shorten the very muscle we are trying to lengthen.
Focus on Proper Form
We should all be focused on proper form in our yoga which means maintaining an elongated and decompressed spine in all poses. Most of the time when we are ‘pushing our limits’ we deviate from proper posture and begin to compress our spine or take our joints out of the desired posture. Getting one’s heels to the floor in a downward dog is not a worthy goal if it means negatively altering the posture of our spine.
Our body is not our enemy that we must whip into shape. Our muscles are exactly the way we have been asking them to be. We should not treat them like a misbehaving animal when they display the shortness our constant daily postures have enforced on them. We should work with an idea that we have plenty of time to resolve our muscle issues. After all, how long have we been keeping our muscles short – weeks, months, years?
Work to your limits but not through your limits
We would all love a limitless life in theory, but that is not possible in reality. Our limits serve a vital function. Yoga is here to help us explore our limits. Every pose can reveal to us our the special relationship our body has with each vital part of itself. Short hamstrings are merely an expression of an entire body out of balance. We cannot correct their shortness by simply pushing past the safe physiological limits inherent in the muscle itself.
Yoga is here to reveal to us what our limits are. Upon finding those limits we should continue to work with gentleness and respect for our body’s needs. Tight muscles are only a symptom of a body out of balance and it will take proper muscle strengthening techniques along with proper posture to fully resolve the issue. This will take time and we should take all the time we need to safely resolve the issue.
The best way for us to safely work is to keep all of our stretch sensations mild and comfortable. When a muscle is tight, we should look to the other side of the joint for a potential weakness. In the example of tight hamstrings in a downward dog, the likely culprit is weak quadriceps muscles. However, it is just as likely there is some weakness in certain core muscles. You can explore more about increasing muscle length properly in my four part series on the subject.
For now though, no matter if an instructor tells you to ‘push your limits’ – please, for your own sake, respect your limits. Work within the comfortable range for your muscles. As I tell my students constantly. You can go right up to the door (your limits) but don’t try to barge into the room. Wait to be invited.