Does stretching work? I want to increase my flexibility so I should stretch more, right? These questions are asked all the time in the physical therapy setting, and my answer may surprise you! Before we discuss if stretching works, we need to first discuss the underlying reasons for inflexibility or stiffness.
Often, when people are asking me about stretching and flexibility, they are referring to their hamstrings, so let’s use that for our example. As Americans, we spend the majority of our time sitting in chairs, and not squatting to full depth. As a result, we often get significant tightness in the posterior chain (hamstrings, calves, low back). However, I frequently find that “tightness” is actually an underlying weakness. Think about it this way: if your hamstrings are very weak, then your brain likely doesn’t trust you to stretch that muscle to its full possible length, because it may fear injury. So, instead of a true “tightness” we are actually seeing an underlying “tone” that is being controlled by the brain due to weakness. When we are able to strengthen the muscle through a full range of motion, it can greatly improve flexibility overall.
However, more significant stiffness and tightness can arise following casting or wearing a boot. In this case, the stiffness can be more difficult to shake, but the same principles can apply. In the case of recovering from fracture or immobilization, you should get some help from a PT to facilitate the recovery.
Now that we understand that flexibility can improve with increased strength, how does that compare to static stretching? Traditional stretching has mixed results in the literature, but it has been shown to improve length of muscle with consistent stretching for at least 90 seconds, for several months. But, taking the knowledge we have about increased strength leading to increased flexibility, can strength training work just as well for improving mobility?
Thankfully for us, a study that is about to be published soon helps provide some answers for us. This meta-analysis examined 11 different studies comparing static stretching and strength training of different methodologies. This heterogeneity of the studies is actually to our benefit because we all have different approaches to stretching and strengthening, so it is a good representation of reality. The amazing results from this study show that static stretching is no different from strength training for improving range of motion! In other words, you can utilize strength training instead of stretching to achieve the increased flexibility you desire!
So, wait a minute. I thought that strength training just made people stiffer and tighter? It doesn't have to! How are we to maximize the benefits for flexibility from strength training? Well, let’s consider how the brain perceives tension and how it trusts us to move safely. If we consider that our brain only trusts us for a small range of motion, we need to strengthen through a wide range of motion to convince the brain to allow us to “own” that new mobility. To make this clear, let’s look at the hamstrings again. The best exercise to improve your hamstring range of motion is the single leg deadlift. But you need to be sure to perform this exercise deeply and into the feelings of hamstring tightness you may feel. By strengthening into the tightness (but never into pain) it allows you to improve your mobility. This same principle can apply to other exercises such as heel raises, squats, pullups, or lat pulldowns.
I know this can be hard to visualize, so if you need help understanding how this can benefit you, please don’t hesitate to reach out to me at firstname.lastname@example.org. In summary, by exercising through a full range of motion, you can achieve improved range of motion comparable to stretching!
Thanks for reading,
Afonso, J., Ramirez-Campillo, R., Moscão, J., Rocha, T., Zacca, R., Martins, A., ... & Clemente, F. M. (2021). Strength training is as effective as stretching for improving range of motion: A systematic review and meta-analysis.