Hamstring Injuries

The hamstrings are a group of three muscles running down the back of the thigh, working together to bend the knee and extend the hip — both essential actions in running, jumping and sprinting. A hamstring strain happens when fibres within one of these muscles are overstretched or torn, most often during rapid acceleration, sprinting, or a sudden lunge or overstretch, such as reaching for a ball or slipping while running.

Hamstring injuries are one of the most common injuries in running-based and field sports — football, athletics, tennis and basketball among them — but they’re not limited to athletes. A fast start from standing, an awkward stretch, or overloading a fatigued muscle late in a match can all be enough to strain the hamstring.

What causes hamstring injuries

Most hamstring strains occur when the muscle is asked to generate force while lengthening — the “eccentric” phase of sprinting, where the hamstring decelerates the leg just before the foot strikes the ground. Fatigue, insufficient warm-up, a previous hamstring injury that hasn’t fully rehabilitated, or a sudden increase in sprint volume or intensity are all common contributing factors. Reduced flexibility and strength imbalances between the hamstrings and the quadriceps or glutes can also leave the muscle vulnerable under high-speed load.

Severity varies considerably. A mild strain might involve a small number of overstretched fibres and settle within a couple of weeks, while a more significant tear can involve a larger portion of the muscle, visible bruising, and a much longer recovery. Hamstring injuries are also notorious for recurring — largely because many people return to sport as soon as the pain eases, before the muscle has regained the strength and length needed to tolerate sprinting again.

Symptoms

Symptoms range from a mild pulling or tightening sensation felt during or after activity, through to a sudden, sharp pain at the back of the thigh at the moment of injury — often described as feeling like being struck or kicked. More significant tears can cause bruising and swelling over the following day or two, along with pain on stretching, sprinting, bending forward, or even sitting for long periods. Walking is usually still possible, but running, especially at speed, is typically painful and limited.

When to see a physiotherapist

Most hamstring strains are well suited to physiotherapy assessment and management. It’s worth being seen promptly rather than waiting to see if it settles, since early guidance on the right amount of loading — enough to stimulate healing without aggravating the injury — has a real bearing on how well and how quickly it recovers. Tell us if you hear or feel a sudden “pop” followed by significant swelling, bruising and difficulty bearing weight — that can indicate a more complete muscle tear or tendon injury, and Andrew will assess it and refer you on if imaging is needed to guide management.

Physiotherapy treatment for hamstring injuries

Andrew’s assessment determines the location and likely severity of the strain, which shapes how the rehabilitation programme is staged. Treatment centres on a structured exercise rehabilitation programme, progressed in phases:

• Early-stage loading — gentle, pain-free movement and isometric muscle activation to maintain strength without aggravating healing tissue, alongside advice on managing swelling in the first few days
• Progressive strengthening — gradually reintroducing load through the hamstring, including the eccentric, lengthening-under-load exercises that most closely mimic what the muscle needs to tolerate during sprinting
• Flexibility work — reintroduced once the acute stage has settled, since aggressive stretching too early can aggravate a fresh strain
• Sprint-specific and sport-specific loading — building back up through jogging, striding and eventually full-speed sprinting, along with any change-of-direction or kicking demands specific to your sport, before clearing a return to training and competition

Throughout the programme, Andrew monitors how the hamstring is responding and adjusts the pace of progression accordingly — pushing too quickly is one of the most common reasons a “healed” hamstring strain recurs within the first few weeks back at sport.

What to expect from treatment

Mild strains often improve noticeably within one to two weeks, while more significant tears can take six to eight weeks or longer to fully rehabilitate before a safe return to sprinting and sport. Andrew will be clear with you about which category your injury falls into after the initial assessment, and will explain the reasoning behind each stage of the programme rather than setting an arbitrary timeline. Pain easing is usually not the signal that you’re ready to return — regaining full strength, flexibility and confidence under sprint-speed load is what actually matters.

Preventing recurrence

Hamstring injuries have one of the highest recurrence rates of any soft tissue injury, and the single biggest contributor is returning to sport before rehabilitation is complete. Completing the full staged programme — not just resting until the pain settles — is what builds the strength and sprint tolerance needed to protect the muscle once you’re back to full training. For athletes with a history of hamstring strains, an ongoing maintenance programme of hamstring and glute strengthening, alongside proper warm-up routines, meaningfully reduces the risk of it happening again.