Ode to Flexibility: Stretch vs Strengthen
Due to my profession people often tell me about their tight muscles. (Not just clients. Anyone I meet who learns what I do.) Accompanied by “I should/need to stretch more”. I’m here to let you know there's more than one option in attaining flexibility and/or reducing tension and stiffness in problem areas. I’ll be specially referencing static stretching (SS) and resistance training (RT) here. Multiple studies have shown RT is as effective if not potentially more effective than static stretching. (1, 2, 3, 4, 5)
SS can be a great way to increase flexibility, calm the mind and center oneself. Stretching has long been considered the norm for increasing flexibility and as pre exercise prep but unfortunately SS doesn’t do what we think it’s doing.
SS does not increase muscle length but increases tolerance for the discomfort associated with the stretch. This is why to improve flexibility one has to keep up with SS to maintain it.
SS does not warmup muscles. SS prior to exercise reduces muscle strength and sports performance for activities like running and jumping. In fact, loss of strength that occurs with SS is well documented and is referred to as “stretch-induced strength loss”. This effectively does not reduce the risk of injury during strenuous activity. (6)
It’s also important to note there is one component preventing a stretch going beyond where one can stretch called the stretch reflex. This reflex causes the muscles being stretched to contract and resist the stretch. The name sounds counterintuitive but it’s the reflex that occurs during a stretch, hence the stretch reflex. Theoretically this is to protect the muscle from tearing because the muscle and tendon don’t have the strength capacity to support the deformation of the area. Before tight hamstrings everywhere curse this reflex it’s what keeps those with poor posture upright and this is just one example. Let’s say we’re slouching all day at our computers: collapsing into our front body with shoulders rolled forward and our back curved like a question mark. All the muscles in our back feel the stretch and the stretch reflex makes those same muscles contract so we don’t keep going face first into our screens. Think of this whenever you stretch and can’t seem to go any further even after sustaining the stretch for 30s or more for multiple reps.
All this info and I am still an advocate for SS. I find it meditative and refreshing but I never do it before I’m to engage in exercise or anything remotely strenuous. I static stretch because I enjoy it.
If anyone should feel compelled to continue to SS regularly or occasionally please be clear on your intent as to why you’re doing it.
If static stretching isn’t terribly appealing but flexibility is, then consider RT. RT can be done with resistance bands, body weight or additional weights. The studies I read specifically cited RT in full range of motion (fROM). There are two parts to any fROM exercise. 1. Concentric contraction is the lifting of the weight. 2. Eccentric contraction is the lowering of the weight. (This simplified explanation is for body weight and free weight exercises. It may be the opposite on machines such as for the lat pull-down.) It’s within the eccentric contraction when the working muscles are contracting in a long position that creates the most tension which brings us to the inverse stretch reflex aka Golgi tendon reflex. When a muscle experiences tension it stimulates sensory receptors (known as the Golgi tendon organs) within the ends of the muscle into the tendons which cause the muscle to relax. When the tension is extreme it can cause muscles to suddenly relax. In workout terms this is known as muscle failure or training to failure. I believe it’s this combination of developing strength and stimulating the Golgi tendon reflex that effectively support flexibility. Due to active stress in the long position the muscles learn it is safe to be in that position, so the stretch reflex is not stimulated during passive stretching so soon. I’m sure there are greater neural, morphological changes happening too but I haven’t read those studies yet.
To take up RT solely for flexibility has so many additional benefits. One gains greater physical strength and endurance. It improves motor control, cardiac, brain and joint function, enhances bone density, as well as reduces the risk of injury, depression and anxiety. Resting metabolism improves because muscle requires more energy. The more muscle one has the more calories one can burn passively.
When considering taking up RT please do so thoughtfully, gradually and ideally under supervision to begin with to ensure correct form or ensure proper muscle engagement.
Any thoughts on this article? I’d love to hear from you. Please share this article and spread the word on flexibility!
To continue the Flexibility series, next week static stretching versus dynamic stretching.
Until next we meet.
“A Comparison of the Immediate Effects of Eccentric Training vs Static Stretch on Hamstring Flexibility in High School and College Athletes” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2953312/#!po=1.78571
“Eccentric Training and Static Stretching Improve Hamstring Flexibility of High School Males” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC522148/#__ffn_sectitle
“The Effects Of Eccentric Training On Lower Limb Flexibility: A Systematic Review” https://bjsm.bmj.com/content/48/7/648.2
“Effects of transient muscle contractions and stretching on the tendon structures in vivo” https://onlinelibrary.wiley.com/doi/full/10.1046/j.1365-201X.2002.00976.x
“Resistance Training vs. Static Stretching: Effects on Flexibility and Strength” https://journals.lww.com/nsca-jscr/Fulltext/2011/12000/Resistance_Training_vs__Static_Stretching__Effects.22.aspx
“Current Concepts In Muscle Stretching For Exercise And Rehabilitation” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3273886/