Get your mind out of the gutter—this is about muscles. The difference between good and bad stiffness is real. When a muscle is truly limited in length, the risk of injury goes up—think strains and tears—and movement patterns can become faulty along the chain of joints and muscles.
In many fitness assessments, like the Functional Movement Screen, people—especially athletes—often score poorly and show clear right/left asymmetries. That leads to a push for corrective exercises aimed at lengthening hamstrings. Ironically, for many NBA players, tight hamstrings are part of what allows them to jump so high. So stiffness isn’t always a bad thing and doesn’t always need to be “fixed.”
Keep in mind that the ASLR (Active Straight Leg Raise) screen isn’t strictly a hamstring length test. It can hint at hamstring length, but what we’re really looking at is the ability to flex and extend the hip. Tight hamstrings can limit that, but the bigger goal is teaching people to get into better positions. By improving stiffness in other areas and optimizing alignment, what looks like “tightness” can disappear when the nervous system senses a safer, more efficient position.
Core-engaged, active straight leg raises involve engaging the anterior core to promote a posterior pelvic tilt, which reduces low-back stiffness and helps improve range of motion. The aim is to get movement from the hips rather than the lower back.
As for the hip flexors, many people have stretched them for years without lasting results. The idea of a persistent, “BS” hip flexor stretch often ends up increasing stiffness in the lower back and the front of the hip capsule. A more effective approach is a real hip flexor stretch that strengthens and coordinates the anterior core and glutes, addressing the actual problem rather than just chasing a feeling of tightness.
Then there are the lats. Stiff lats can be a mixed blessing. In overhead athletes and others, tight, overactive lats can pull the shoulder into depression, downward rotation, and adduction, and can contribute to lumbar extension. This pattern is something Postural Restoration Institute techniques describe, with a pelvis and diaphragm misalignment that keeps the nervous system in a heightened state. Overactive lats also make it harder to raise the arms overhead and to access the lower traps, which work with the upper traps and serratus to rotate and position the shoulder blade properly. Coaching someone to down-regulate the lats when flexing, externally rotating, and abducting the shoulder can make a big difference.
Practical drills you’ll see in programs include bench thoracic (T-spine) mobility work and wall lat stretches with thoracic extension and lift-offs. These aim to balance the lats and improve thoracic mobility.
When the lats are activated appropriately, they can boost performance in the weight room. They play a major role in how effectively you can brace and pull during heavy lifts. A common training cue for deadlifts is to use a band attached to the bar and a fixed object so the trainee learns to “pull the bar toward them” and keep the lats engaged throughout the lift. There are other options to explore as well, and you’ll often see these ideas discussed in recent posts. In this light, stiffness isn’t inherently bad—it’s about using it contextually.
Bottom line: whether stiffness is good or bad depends on the situation.
