What cause a muscle to feel tight? Should I stretch?

I get asked almost daily about muscle tightness or stretching. Stretching has a certain place in our culture that’s up there with juice cleanses being the supposed elixir of life. Something tight, or hurting? Stretch it out! Need a morning routine, warm up routine, or cool down routine? Let’s throw in some stretching. Have a new injury? Must be from some tight muscles! Right?

Well… maybe. As always, the truth is complicated. The sensation of muscle tightness, or needing to stretch a muscle, is actually a complex neurological phenomenon. The brain is constantly trying to interpret millions of pieces of incoming data from the body, sent up through the peripheral nerves and spinal cord. It then subconsciously has to make sense of all of that information, and either disregard it, or use it to try to motivate a conscious action. The sensation of muscle tightness or a need to stretch comes about in response to stimulus from the body, and it gets you to pay attention to the area in question, and then move it around. This is sometimes completely appropriate. For example, if you’re all cooped up on an airplane or sitting for a while at a desk, the sensation of needing to stretch will motivate you to get up, move around, and get some blood flow. This can avoid blood clots, arms or legs falling asleep, occlusion of blood flow to nerves, etc. — all good things!

However, where the story gets more complicated is when you have a frequent need to stretch the same area, all the time. When you feel like you compulsively need to stretch the same thing every day or even every hour. Or when that feeling of muscle tightness or needing to stretch starts to border or pain or real discomfort, and interrupts your day or your activities. When stretching alone doesn’t resolve these uncomfortable sensations, or when the relief from stretching is only temporary, then we want to dig deeper. There’s probably a root cause to the muscle tightness that isn’t truly solved by stretching it out.

Let’s dig in.

First, some basic terminology and biomechanics:

  • A muscle’s length is defined by the distance between its origin (where it starts), and its insertion (the endpoint).

  • When a muscle contracts, the distance between the origin and insertion gets shorter or closer together. This shortening generally creates joint motion — for example when the bicep gets shorter, your elbow flexes.

  • When a muscle relaxes, this distance between origin and insertion lengthens back to baseline

  • Generally speaking, when we stretch a muscle, we are doing a movement that takes the origin of the muscle even further away from the insertion than it would normally be while relaxed.

  • The position in which we can stretch a muscle is always opposite the direction in which it contracts. This makes sense, because a contraction brings origin and insertion together, and a stretch pulls them apart. For example, when the hip flexors contract, the hip and femur move forward and up. To stretch or lengthen the hip flexors, we bring the leg behind us. This can get more complex with longer muscles that cross several joints, but the same basic principle applies.

  • Let’s take it one step further. If you feel hip flexor tightness when we are trying to get your leg behind you, a stretch might be appropriate. But, if you feel hip flexor or front-of-the-hip tightness when the leg is forward or in front of you, such as in a squat or leg lift, that sensation of tightness is likely caused by something other than muscle length.

The Thomas Test. The first picture demonstrates hip flexor tightness, as the hips do not come to full extension. In the second picture, the hips come past neutral into extension, demonstrating fairly normal hip flexor length. A hip flexor stretch is likely appropriate for picture #1. But if you are picture #2, your hip flexors are not short, and any tightness you feel is likely caused by something other than muscle length.

The Thomas Test. The first picture demonstrates hip flexor tightness, as the hips do not come to full extension. In the second picture, the hips come past neutral into extension, demonstrating fairly normal hip flexor length. A hip flexor stretch is likely appropriate for picture #1. But if you are picture #2, your hip flexors are not short, and any tightness you feel is likely caused by something other than muscle length.

Still with me? Cool. So with those basic principles in mind, what then can cause a muscle to feel tight or that it needs to be stretched? There’re actually many reasons.

  1. Muscle “shortness”: This is main reason that most people think of — if a muscle feels tight, then it must be short or immobile, and so I should stretch it out to make it longer, right?. It’s a simple story, and this is sometimes the case. But, it’s also one that we can test. In my physical therapy evaluations, I often do objective muscle length testing, such as the Thomas Test for the quadriceps and hip flexors, to determine if a muscle is truly shorter in length than we want it to be. What I mean by this is: Can the origin and insertion of a muscle get far enough apart to permit normal joint motion? If not, then we can certainly prescribe some focused stretches to attempt to lengthen that muscle. Perhaps surprisingly given how tight most people say they feel, I don’t find glaring muscle length issues as often as you’d think. I find some of the other root causes for muscle tightness to be more common.

  2. Joint Restrictions: We’re starting with the easy ones. Sometimes muscles have appropriate length, but the joints themselves that have to move don’t have adequate motion. Like a hinge that gets stuck with the door only part-way open. This can then cause a feeling of tightness. Again, this is testable, usually with passive joint motion in a non-weightbearing position. Minimizing the effect of gravity, muscle contractions, and other forces as much as possible, can we move the joint through its normal range of motion? If not, and in the absence of true muscle length issues (see #1 above), we then can prescribe joint mobilizations, which are similar to stretches, but are more focused on getting the joint to move better or differently within its joint capsule. For example, when the ankles feel tight, we can test calf length and talocrural joint motion. A calf stretch would hit the muscle, while a specific talocrural mobilization into plantarflexion or dorsiflexion would more directly affect the joint. However, I often find that “tight” areas have good muscle length, and excellent passive joint mobility. So if we strike out on #1 and #2, what else can cause muscle tightness?

  3. Stress: A big part of the body’s sympathetic stress response, which we’ve discussed briefly before, is generating muscle tension. Why? Because the stress response is preparing you to deal with a potential threat. Some resting muscle tension makes you more ready to spring into action. It’s like a baseball player getting ready to sprint in any direction after a ball. The stress response can bring you slightly up onto your toes, cause you to shrug your shoulders up, bring some resting tension into the hip flexors, and cause some defensive internal rotation of the shoulders and chest. It’s no wonder that some of the most common places that people feel tight are their shoulders, upper back, hip flexors, and calves! Stretching for some people can be incredibly stress relieving and therefore helpful, but for many people stretching alone doesn’t get to the root cause of their stress, and so that tension comes right back.

  4. Compression: Compression of a muscle can cause muscle tightness or a need to stretch as well. This is often the case with the hamstrings. We sit on them for long periods of time, and then they start to feel tight as there is perhaps slightly occluded blood flow or altered neural inputs around the muscles. The sensation to stretch can get us moving and temporarily relieve the compression. However, sometimes stretching a muscle that has been sensitized by compression can result in more pain. For example, the gluteal muscles and tendon (outside and back of the hip) can be irritated by compression, and overstretching them further exacerbates the issue.

  5. Movement Patterns: The way in which we move can generate or relieve muscle tightness. The hip flexors are another common example. I frequently see patients who have been diagnosed with “hip impingement” who report incredible hip flexor tightness when they squat down. This is a bit of a strange place to feel tightness, as based on our biomechanics lesson from the beginning of the article, the hip flexors should be pretty relaxed at the bottom of a squat. Stretching the hip flexors with the leg behind you (hip extension) doesn’t quite make sense, biomechanically, as a way to improve tightness in the front of the hip at the bottom of your squat (a position of hip flexion). When I analyze their squat form, I often see a quadricep-dominant pattern with knee valgus (knees dropping in), which can then cause compression of the hip flexor muscles, possibly overactivity of the adductors, and perhaps overstretching of the hip abductors (outside of the hip). This can lead to a sensation of tightness around the hip joint. If we help teach a new movement pattern, with improved hip stability and alignment, that tightness usually disappears.

  6. Static Positions: This one makes sense. If you stay in one position for a long time, your body might start to feel tight or trigger a need to stretch or move around. However, if you job requires you to be in static positions frequently, then we might want to dig a little deeper - can we vary your position, or change something so that you don’t always have a compelling need to stretch?

  7. Overuse: If you use a muscle a lot, it can start to feel tight due to sustained muscle contraction. Imagine that you are squeezing your hand tight into a fist all day. Your finger and forearm muscles will start to get tight, the finger joints might start to ache, and you’ll want to stretch your hand out. This will relieve that sensation, but if you go right back to squeezing your hand tight, stretching along won’t solve the problem. The root cause is that you’re squeezing the muscles tight all the time. This can be common with calf tightness. Other leg muscles may not be engaging to support the calf, and the calf can then start to feel really tight or even get strained because it’s working all the time.

  8. Injury: Pain or an injury can cause muscle tightness for all sorts of reasons. Muscles can tense up around an injured joint, ligament, or tendon. Swelling can feel like tightness or tension. Altered movement patterns or postures in response to pain can cause tightness. Injured nerves can trigger muscle tightness along their path. For example, an injury to the lower back or sciatic nerve can cause hamstring tightness, as the sciatic nerve runs through the hamstrings. We want to be careful with stretching in the context of pain or injury, as stretching actually exacerbate or worsen some injuries, particularly nerve, tendon, and joint injuries.

  9. Weakness: A muscle that is overloaded or not quite strong enough can feel tight. This is similar to overuse — if a muscle is working near its maximum capacity frequently, it’ll feel tense. The antidote here is not stretching, but rather strengthening. I find that the hamstrings — a common area of perceived tightness — are compressed throughout the day with sitting, and then often overstretched but never strengthened. Another example is the hip flexors and hip abductors — many people feel really tight or restricted if they try to lift their leg straight forward or straight out to the side. This actually takes an incredible amount of strength in the muscle groups around the hips, and if those muscles are not strengthened, the body may feel tight as you try to move into those positions.

    • As a side note, it’s a common misconception that strengthening a muscle will make it shorter, and there’s nothing further from the truth. Take the bicep as an example — unless you’ve had an elbow injury, almost everyone can fully straighten their elbow, which is the full length of the bicep. Strengthening the bicep does not impair your ability to straighten the elbow. In fact, it takes more strength for a muscle work at it’s full length, because there’s more motion and joint forces to control. Think about holding a weight out in front of you with a straight arm (full length of the bicep), versus in close to the body (bicep in a shorter position with more leverage). It takes more strength to hold something with a straight arm, in that lengthened position. So dancers, yogis, aerialists, climbers, and other athletes who want full expression of strength in extended positions actually need not just flexibility, but crazy amounts of strength as well.

Let’s put all of this together for one notorious area of muscle tightness and needing to stretch: the hamstrings. I’ve almost never met a person who doesn’t think they need to stretch their hamstrings more. I’ve even seen individuals who can put their palms on the floor — a pretty incredible level of hamstring flexibility — report feeling like they still need to stretch their hamstrings more. What’s going on here?

  • The hamstrings are frequently subject to static positions and compression with sitting.

  • Unless you’re working with a good strength coach, hamstrings are frequently overlooked for strengthening. When I perform manual muscle testing of the hamstrings, I often find that they test weak or even cramp up immediately, a sign they they are overloaded or not strong enough to create adequate resistance during the test.

  • Lower back injuries are common, which can cause sciatic nerve tension and therefore hamstring tension.

  • Many people struggle with proper hip hinging and squatting technique, which can then result in altered hamstring activity or increase neural tension.

Hopefully it’s more clear at this point that there’s many potential reasons why the hamstrings can feel really tight. I often have patients who are have all of these factors at the same time. There’s no way that stretching or foam rolling alone will resolve the issues — we have to dig into all of other root causes to make real progress.

Solutions: So what can we do about muscle tightness? If we understand the root cause, then hopefully the solution becomes more clear. Here’s a few common ways:

  • Strengthening: This is perhaps our most powerful tool. Stronger muscles can better meet the demands placed upon them, and therefore feel less tight. Strengthening around a tight muscle can also help support it, again decreasing perceived tightness. Eccentric strengthening, which refers to lengthening a muscle under load, is a particularly excellent way to both improve muscle length/flexibility and strength simultaneously. This works beautifully on the hamstrings when done correctly, but can applied anywhere in the both.

  • Move more: If you work at a desk or don’t move much throughout the day, simply moving more often should help. The body craves movement.

  • Improve your movement patterns: Can you do a proper squat, hip hinge, lunge, overhead press, and row, with good technique? Often, improving these patterns helps to resolve muscle tightness or tension because you are loading the joints and muscles in a way that optimizes function. Or, you’re just moving in a new way, and that can bring muscles into new positions that don’t feel so tight.

  • Manage stress: If you’re a modern human that works a full time job, has a smartphone, pays rent or a mortgage, uses email and social media, and uses an alarm clock, then we can assume that you have some baseline level of stress. Do you have a breathing or meditation practice, or other ways to unwind and manage that stress? Do you ever slow down and take deep breaths? This can be a bigger piece of the puzzle than you migh5 think.

  • Stretching: Yes, stretching can work in some cases! I don’t want you to come away from this article thinking that I’m anti-stretching. I am a huge fan of appropriate stretching, and wary of compulsive or over-stretching, because at best there’s no need for it, and at worst it can exacerbate some issues. If you’ve been in a static position for a while, have compressed some muscles, or want to do some light movement to relieve stress, then stretching can be great. If you’ve had some objective tests of muscle length performed and need to improve a few area - great. However, you should feel better after you stretch, and if you always need to stretch the same areas, or if the sensation of tightness, tension, or pain returns quickly, then we should try something else.

  • Tissue work: This one is also obvious to most people — do some massage, foam rolling, or self-tissue work on a tight muscle, and it can feel better. But just like stretching, this often does not get to the root cause of the problem. If you find yourself trying to dig into an uncomfortable area all the time, then there’s probably something else going on.

  • Evaluate injuries: If there’s an injury to a joint, nerve, ligament, or other structure, we need to treat that appropriately with a comprehensive approach. Treatment may include many of the elements describe above, along with specific joint or nerve mobilizations or other treatment of injured tissues.

Do you have muscles that frequently feel tight? Do you stretch a lot without lasting relief? If you need help managing these issues, click below to schedule a FREE phone consult and strategy session to discuss a path forward.