Tight Hamstrings? It's Not What You Think

Tight hamstrings? You’re not alone. It’s a common complaint that physiotherapists hear. It’s often thought that the fix for tight hamstrings is to stretch them for several minutes everyday. While passive stretches might help your hamstrings feel less tight temporarily, it doesn’t actually improve that feeling of tightness over the long-term. Instead, to safely increase hamstring flexibility, part of the solution is to strengthen the muscle. Let us explain.

What’s a Hamstring?

Hamstrings are a group of three muscles on the backside of your thigh. Together, they work to flex (bend) your knee and extend (straighten) your hip. Knee flexion and hip extension are necessary for walking, running, sitting, and most other daily movements. Stiff hamstrings impact the ease with which you (literally) walk through life.

Bodies are complex, and muscle groups are intricately connected. Thus, tight hamstrings have consequences on other parts of your body, such as posture. If you have tight hamstrings, chances are it’s difficult to sit comfortably on the ground. Your ability to bend down and pick something up might be a challenge. Maybe you've experienced that tightness when you've tried to reach to tie your shoes, or when you've been sitting for too long. Tight hamstrings can be uncomfortable, limiting, and restrictive on functional movement. So what’s the magic remedy for tight hamstrings?

The “Tight” Elephant in the Room

First of all, let’s clarify what we mean by the word “tight”. It’s common to think of something that is tight as shortened. If we imagine tight hamstrings as shortened hamstrings, the obvious remedy would be to do the opposite—lengthen the muscle. Lengthening the muscle is often associated with passive stretches. In a passive stretch, something other than your muscles is required to hold the position. An example of a passive hamstring stretch is a seated forward fold, in which the ground keeps the straight leg in place. A passive hamstring stretch might feel good in the short-term, but it doesn’t actually “lengthen” the muscle or reduce “tightness” over the long-term.

While the word “tight” is helpful imagery, it doesn’t actually describe the mechanical behaviour of the muscle. A tight hamstring does not necessarily mean a structural shortness. Instead, the feeling of tightness is a proprioceptive input from sensory receptors in the muscle(s). These sensory receptors detect changes in length. Thus, even people who are very flexible will feel “tight” at their end range of motion (ROM).

To Increase Flexibility, Increase Strength

To increase hamstring flexibility, you actually need to increase strength. When you move outside your active ROM, your nervous system senses it as a possible danger and tells you to stop by making it feel tight. In this case, you need to build strength into a deeper ROM. Over time, this will teach your nervous system that a deeper ROM is a safe, supported and functional position to be in. If all you do is passively stretch and then not use that greater ROM functionally, the nervous system won’t adapt, and you’ll continue to have stiff hamstrings.

How to Increase Hamstring Strength

There are a few methods to increase hamstring strength in a deeper ROM. Here are two examples we use in our virtual physio practice:

Proprioceptive neuromuscular facilitation (PNF). This is a technique in which you intentionally contract and then relax the muscle. For example: lie on your back and raise your right leg towards the ceiling. Try to keep your knee straight. With a strap or clasped hands, pull your leg closer towards your chest for a few seconds. This is a passive hamstring stretch. Then, interlace your fingers and hands behind your knee and push into your hands. Actively straighten your knee as much as you can. Keep that engagement, straight knee and try to lift your toes a little higher as you try to draw your leg closer to your chest. This is an active muscular engagement into an increased ROM. Repeat the passive stretch and the active engagement for a few rounds on each leg.
Eccentric exercises. These are exercises in which you contract the muscle as it lengthens. Think of “eccentric” as applying the brake pedal to work against gravity. For example, an eccentric pull-up would be a controlled lowering down. An eccentric push-up would be slowly lowering your chest towards the floor. For the hamstrings, two great examples are Romanian deadlifts and good mornings.

Tight Hamstrings? Let’s Talk