How Posture Affects Hamstring Length

How posture affects hamstring length (image from

If you had to pick one muscle that you thought was “tight”, what would it be? For most people, whether they are yogis, CrossFitters, runners, office workers or humans, the hamstrings are a literal pain in the ass. It’s no real surprise that the hamstrings are short because we spend a majority of our day seated and slouching, keeping them in a shortened position, rolled up like horizontal blinds.

The hamstrings are the common name for a group of three muscles: the biceps femoris, semitendinosus, and semimembranosus, and are responsible for hip extension and knee flexion. When seated, the knees remain slightly bent, which contributes to shortening of the hamstrings. Many of us also tend to sit on our sacrum, rather than our ischial tuberosities (“sit bones”), which further contributes to shortening of the hamstring group. Our tissues adapt to whatever positions we put them in most often, so if a group of muscle and its related connective tissue spends a majority of it’s time in a shortened position, it will adapt that shape as the “new normal”.

Undoing tightness in the hamstrings has less to do with stretching them, which may only take 15 minutes out of your day, but should be more focused on putting them in better positions throughout your day, you know, the other 23.75 hours a day. Basically, stop sitting and slouching so much.

The moral of the story for any movement dilemma seems to be move more and tight hamstrings are no different.

Here are my favorite self-care tools and moves to help alleviate tension in the hamstrings:

First, check out this great video by my friend and fellow YTU teacher, Brooke Thomas – the Insta Hamstring Lengthener. In the video, Brooke uses a Classic YTU Ball in the tote to roll through the hamstrings.

Another piece to consider in your quest for pain-free hamstrings is the effect of tension in the pelvic floor. Your pelvic floor, which lines the basis of the pelvis and torso, shares fascial connections with everything around it, including glutes, hamstrings, adductors (inner thighs) and more. If there is tension here, and there probably is (or in any of the other places), this is not a place to ignore. Check out this great video by Dr. Kelly Starrett and Jill Miller on about pelvic floor dysfunction and why you should be massaging it. This does require you pay to watch it, but it is completely worth it. Pelvic floor massage in a very brief nutshell is simple – while sitting on a chair, place a super soft and grippy YTU Ball (DO NOT USE A LACROSSE BALL!) in between the diamond shape created by your pubic bone, your tail bone, and your two sitting bones. While sitting, attempt to engage the pelvic floor by drawing up, as if you were going to pick up the YTU ball. You can also hunt around for tension by allowing the YTU ball to move around or change the position of your hips to uncover interesting sensations. Give it a try!

Thirdly, there are people who do not need to stretch any more. These are the people who can touch their toes without any problems and take their feet behind their head without missing a beat. For you my friends, stop stretching your hamstrings. There comes a point where you are no longer stretching the muscle itself (because it is completely overstretched) and are instead tugging on ligaments and tendons, which do not have the same pliability and resiliency that muscle tissue does (Read more about the science of stretching and what are you actually stretching here). If you fall into this category and still have grouchy hamstrings, check out this great blog by Jill Miller about becoming stable in an unstable body.

Flexibility and strength exist on a spectrum. It is no better to be on the far right or the far left when it comes to the flexibility of our tissues. If you are overstretched, a little bit of strength training to give your muscle some tone will be helpful. If you are a stiff as a board, because of either strength or no-movement, then some stretching and movement will be the ticket. Wherever you fall on the spectrum, move more!