Yoga & Stretch Reflex

Yoga is a beautiful and highly effective practice of mental focus and physical stamina but you don’t have to do yoga or be good at it to reap the benefits to be had by stretching. One of the valuable reasons to participating in 60-90 minutes of stretching a couple times a week is that it forces you to stretch for longer then the quick and infamous post workout quad, pectoral and touch your toes stretches that really don’t do much for creating flexibility. 

There are a series of events that happen during a stretch. When a muscle is stretched, something called muscle spindles are also stretched. Muscle spindles record the change in length (and how fast) and sends signals to the spine that will convey this information. This triggers the stretch reflex, which essentially tries to resist the change in muscle length by causing a stretched muscle to contract. 

To put it into perspective, the stretch reflex occurs when performing a plyometric exercise like jumping. The muscle spindle senses that a muscle is lengthening and tries to protect the body from injury as if you were to pull a muscle, by contracting the muscle even more. The more sudden the change in muscle length, the stronger the contractions will be. Yoga is all about slow and purposeful stretches. In layman’s terms, this allows for the muscles to realize “oh this is ok, I’m stretching and don’t need to protect the muscle by contracting it even more.” One of the reasons for holding a stretch for a prolonged period of time is that as you hold the muscle in a stretched position, the muscle spindle habituates (becomes accustomed to the new length) and reduces its signaling. Gradually, you can train your stretch receptors to allow greater lengthening of the muscles.

The next time you’re in a yoga class or stretching elsewhere, think about your breath and how that relates to muscle relaxation. An exhale is when you find room to deepen into a stretch. An inhale is designed to realign and lengthen the entire body. It may not be until a series of deep breaths that your muscles are ready to release from a contracted state. With practice, muscles can be controlled so that there is little to no reflex contraction in response to a stretch. This type of control provides the opportunity for the greatest gains in flexibility.