Hamstring pain that seems to hang around for months seems to be one of the most common problems for marathon and distance runners.
Hamstring pain can be felt in a number of locations.
Pain up under the crease of the buttock is often due to a Proximal Hamstrings Tendinopathy or Ischial Bursitis.
Hamstrings pain at the top of the thigh on the back of the leg or midway down the thigh is usually a muscle belly issue, ranging from muscle tears to central tendon issues.
And hamstring pain that extends down behind the knee is usually a Distal Hamstring Tendinopathy.
Hamstring pain can usually be diagnosed clinically (in rooms) and may be confirmed with an MRI if needed in most cases.
It’s worth noting that MRI will often show a Hamstrings Tendinopathy for any runner, even when it’s not the source of symptoms (read more about that here).
This an often lead to treatment approaches focused on the imaging findings and not the underlying issue.
MRI will also miss other causes or contributors to hamstring pain such as lower back referred pain and spinal or Sciatic nerve issues closer to the lumbar spine.
These issues can often cause the Hamstrings to malfunction, leading to a secondary pathology in the muscle itself (read more about that here).
Unless the original cause is treated, the hamstring pain will keep coming back.
There are also triggers for hamstrings symptoms, which are very hard to avoid (depending on your sport).
Field and ball sports heavily load their hamstrings during sprint take offs, quick stops and pivoting/cutting movements.
Distance runners will often feel more hamstring pain when they run faster, run while fatigued or run up a slight incline.
Unfortunately those circumstances are very common and quite necessary in each sport.
So we need to explore the reasons why hamstring pain can be constantly felt when running as well as the treatment for each reason.
The anatomy and role the hamstring muscle
The hamstring muscle isn’t a single muscle but a group of four muscles located on the back of the thigh.
At the top end, these muscles attached to the bone you sit on (called the “Ischial tuberosity”) as well as a strong ligament that runs up towards your sacrum and SIJ (known as the Sacrotuberous ligament).
Although these muscles start from a common point at the top, they divide into two subgroups that join on either side of the knee.
Biceps Femoris is made up of two muscles and attaches on the outside of the knee (aka. “lateral” aspect) at the top of the fibula bone.
Semimembranosus and Semitendinosus are the other two muscles and they attach on the inside (or “medial” aspect) of the knee at a junction called Pes Anserine.
The hamstrings crosses both the hip and knee joints, so it can generate and control movement at each joint.
It’s primary role is to slow the leg down as it swings forward (like in walking, just before you put your foot down) and to pull the leg back when it’s in front of you (like when your foot has just landed during walking or running).
The first movement, slowing the leg down as it swings in front, is referred to as an eccentric movement.
Eccentric movements are when the muscle actively resists to control the rate of lengthening of the muscle.
The Nordic hamstring curl is an eccentric hamstring exercise (a very overused and poorly applied exercise though)
After the foot land, the second part of the movement is called a concentric movement.
Concentric is when the muscle actively contracts and shortens.
The pulling movement of a prone (lying) hamstring curl is an example of a concentric movement.
Importantly, the hamstrings muscle group performs almost no functional movements when the leg is behind the hips.
This means that standing or prone hamstrings curls have very little functional benefit for the muscles.
They’ll make the muscle stronger but it doesn’t improve the performance of ay function in a meaningful way.
The 4 most common reasons for persistent hamstring pain
Connective tissue vs muscle fibre tears
When you suddenly injure your muscle (known as an “acute Injury”), we often assume that it’s a tear in the muscle fibres.
Muscle fibre injuries heal pretty well and with a fairly consistent timeframe.
But if you’ve actually damaged the tendon (a rope-like elastic connective tissue that runs through the muscle), healing is much slower.
Tendon tears also require a different approach for your rehab, so the classic muscle tear program wouldn’t be as effective at preparing you for a return to running and sport.
Sciatic nerve involvement
Any irritation to the Sciatic nerve can affect the way the Hamstrings feels and behaves.
This isn’t necessarily Sciatica, although that is one form of Sciatic nerve irritation.
The Sciatic nerve serves two functions for the Hamstrings – it perceives sensation in the area and it controls the muscle activation.
So an irritated Sciatic nerve can give the feeling that the muscle is sore or tight.
It can also make the muscle difficult to control, leading to overactivity and fatigue during regular tasks.
The pain isn’t coming from the muscle…
Referred pain comes in a number of forms, and it can make things very difficult to diagnose and treat.
There is neurological referral from an irritated nerve, like we described in the Sciatic nerve paragraph above.
There’s also Somatic referred pain, where the brain confuses sensory input and interprets that it’s coming from a different region (it’s due to the way that the brain and nerve system is designed, it’s not a learned behaviour).
So pain from the hip or lower back can actually cause Hamstring pain, even though the Hamstrings are not injured in any way.
Inadequate loading and stimulus from the rehab program
Lastly, there’s inadequate rehab and recovery.
This is when you might feel that your muscle is fully recovered because it hasn’t caused any Hamstring pain in the least few weeks.
But it also hasn’t been fully loaded and challenged…
Then when you return to full loading, it flares up again and starts a recurrent cycle of pain and injury.
There are also other injuries that can remain, despite not causing any symptoms.
Tendinopathies are essentially irritated tendons – they become painful with abnormal or excessive loading (excessive relative to what they’ve done recently).
After a few weeks of rest, they won’t cause any Hamstring pain but the condition is still there.
So when you return to sport, it gradually becomes sore again.