The sensation of tightness in the hamstrings is very common and can be caused by a variety of factors.
Often, to reduce this sensation of tightness the first thing that most people will do is stretch the hamstrings. While this might offer temporary relief, it may not be addressing the true cause of the tightness, causing it to return a short time later.
Based on the study of human movement, it has been found that the sensation of tightness in the hamstrings may not be caused by the hamstrings at all. This is because the sensation of tightness in our muscles can be caused by two things: mechanical tightness or neurological tightness.
- Mechanical tightness is when a muscle is in a constantly shortened/contracted state. Over time the muscle(s) will adapt by becoming physically shorter and tighter.
- Neurological tightness results from a muscle being in a constantly elongated/stretched state. Being in a constantly elongated state actually creates tension in the muscle similar to when a rubber band is stretched or when a guitar string is tuned- it becomes tight or "taut" as a result of being lengthened.
So, what does all of this have to do with tight hamstrings? Due to most people's jobs and/or lifestyles they usually end up sitting for the majority of the day. Being seated for extended periods shortens muscles on the front of our pelvis called hip flexors. Over time and the more we sit, the more mechanical tightness develops in the hip flexors because they are in a constantly shortened state. As a result of this, once we do stand up and move around our tight hip flexors actually cause the front of our pelvis and lower back to be pulled forward.
Since our hamstrings attach to the back side of our pelvis, when it [the pelvis] gets pulled forward, it will stretch the hamstrings by putting them into an elongated position. This eventually will increase the amount of tension and the sensation of tightness we feel in the hamstrings because they are constantly being pulled "taut."
The solution is to stretch the hip flexor muscles on the front of the hip that are causing the pelvis to be pulled forward and the hamstrings to be elongated and pulled "taut." This will help realign your pelvis/lower back which will reduce the tension in the hamstrings and sensation of tightness that is felt.