Quads vs. Hamstrings – who’s to blame?

When it comes to hip, knee and low back pain, the major muscles present (and blamed for issues) are the quadriceps and hamstrings. This makes sense as the rectus femoris, one of the 4 quadriceps muscles, crosses at the hip and assists with hip flexion and the hamstrings (biceps femoris, semitendinosus, and semimembranosus) anchor to the pelvis and assist with hip extension.

Because of the position in relationship to one another, the quadriceps and hamstrings work in opposition, known in the body as an agonist/antagonist relationship. When the quadriceps contract, the hamstrings must relax through a process called reciprocal inhibition. Reciprocal inhibition is a reflex that happens simultaneously – your central nervous system (brain and spinal cord) tell one muscle to contract and the muscle on the opposite side of the joint to relax to allow for movement and prevent injury.

The quadriceps and hamstrings are also greatly affected by the position we tend to put them in most often during the day – sitting. The average person sits 14 hours a day. While this may seem like an insanely high number, when you consider time spent at your desk, sitting during your commute, sitting at home at the dinner table or couch, 14 hours doesn’t seem that outlandish.

The problem with sitting is that it leaves are hips and knees in a static position for 14 hours a day. Imagine if you had to keep your hand raised for 14 hours a day – there would be some major side effects from this.

The same thing happens at the hip and knee, we are just more accustomed to it because we’ve been sitting our whole lives.

When seated, the glutes are on stretch, the hamstrings passively shortened (especially if you are slouching and sitting on your tail bone), and the upper attachment of the quadriceps are shortened, while the portion of the quads that crosses the knee is locked long.

So who’s to blame for tight hips and/or lower back? To be honest, it could be either. This is an overly simplified explanation for an incredibly complicated system. Much of flexibility comes from your nervous system trusting that your body has the strength and control to get in and out of positions.

If you are lacking strength in any area, or perhaps even lacking core stability (which many of us are for a variety of reasons), then your brain will not trust that you can get in and out of hip flexion or extension safely.

What to do? Ensure that you have enough hamstring and quadricep flexbility when there is no load on your spine (aka laying down). You can lay face down with a blanket under your hips for a simple quad stretch, or on your back face up for a straight leg hamstring stretch.

If you are able to do both of these with little resistance, than perhaps the issue is less about the actual “length” of the tissues and more to do with your mobility, control and nervous system. Rule out a lack of mobility or control in other joints with the 15-Day Self-Care Startup Guide – I’ll guide you through mobility and corrective exercises for all of the major joints. You’ll also get therapy ball and self-care routines to give you a solid foundatino to start your own tailored self-care routine.

Tiny adjustments to how you move every day will go a long way to helping to resolve pain and improve posture!