Hamstring strain: how long it takes, the rehab that works and how to keep it from coming back

Your hamstrings are the muscles along the back of your thigh. A strain is an injury to those muscles or their tendons, and it usually announces itself clearly: sudden pain at the back of the thigh during activity, pain when the muscle is stretched or tightened, tenderness and trouble using the leg [1]. With a severe injury you may feel a snap or hear a “pop”, and the back of the thigh can swell and bruise within a few hours [19].

How common is it?

Very, especially in sports with sprinting. In a study of elite European men’s soccer teams, hamstring injuries rose from 12% of all injuries in 2001/02 to 24% in 2021/22 [2]. Running or sprinting caused about 6 in 10 of them [2].

They also come back. In that study, 18% of hamstring injuries were repeat injuries, and more than two thirds of those happened within 2 months of returning to play [2]. The physical therapy guideline notes that a previous hamstring strain makes another one about 3.6 times more likely [1].

A note on the evidence: most of this research comes from elite male athletes, especially soccer players. It is the best guide we have, but there is much less data on women, weekend athletes and older adults.

How long does it take?

It depends on the injury. The guideline says time away from sport generally ranges from 3 to 28 days or more [1]. In professional soccer players, recovery time lined up with what an MRI showed:

• Grade 0, nothing visible (13% of injuries)8 days
• Grade 1 (57%)17 days
• Grade 2 (27%)22 days
• Grade 3, complete tear (3%)73 days

Source: Ekstrand et al., British Journal of Sports Medicine, 2012 [3]. 516 injuries, 58% examined by MRI. Times varied a lot, especially for grade 3. Bars are scaled to 75 days.

Most strains are on the milder end, but how you got hurt matters too:

• Sprinting-type injuries happen at high speed. In 18 elite sprinters, the median return to their previous level was 16 weeks [4].
• Stretching-type injuries happen during slow, extreme stretches, as in dance or high kicks. They feel milder at first but took much longer: in 15 professional dancers, the median was 50 weeks [5].
• Injuries near the sit bone or involving the tendon generally take longer [4]. In elite sprinters and jumpers, injuries involving the upper tendon took 73 vs. 31 days with the same rehab program [7].

You do not always need an MRI. The guideline says imaging does not predict return to play any better than a good clinical exam, which looks at strength, how painful the injury was, how many days it took to walk without pain and how much of the muscle is tender [1]. Imaging is useful when something does not fit, when you are not recovering as expected, or when a tendon may have pulled off the bone [1].

The rehab that works

The guideline recommends a progressive, impairment-based program that includes [1]:

• Eccentric (lengthening) exercise, at a level you can tolerate, along with stretching, strengthening, stability work and a progressive running program, to speed return to play
• Progressive agility and trunk stabilization, to lower the chance of reinjury

These are the trials behind those recommendations:

Study	Who	What was compared	Result
Askling, 2013 [6]	75 elite soccer players	Lengthening exercises vs. conventional exercises	Back to full training in 28 vs. 51 days on average
Askling, 2014 [7]	56 elite sprinters and jumpers	Lengthening exercises vs. conventional exercises	Back to full training in 49 vs. 86 days on average
Sherry, 2004 [8]	24 athletes	Agility and trunk stabilization vs. stretching and strengthening	Reinjured within a year: 1 of 13 vs. 7 of 10
Hickey, 2020 [9]	43 men	Exercise up to a tolerable pain level vs. pain-free exercise	Similar time to clearance (17 vs. 15 days), but 15% more strength recovered with the first approach

These trials were small, and the Askling trials were run by one research group. In the Sherry trial, the faster return to sport was not statistically significant; the difference was in reinjuries [8]. A review found lengthening exercises speed return to play, but did not show they prevent reinjury [11].

Some discomfort during rehab can be fine. An international expert panel agreed that rehab should be individualized, that acceptable pain can depend on the activity, and that sprinting should be pain free [10]. The same panel agreed that returning to sport should be based on what your sport demands and what you can do, not just on the calendar [10].

Finish the program. The guideline advises caution about returning to play if you have not completed a progressed program that included eccentric training [1]. With repeat injuries clustering in the first 2 months after return [2], the final stages are where much of the prevention happens.

Injections and medicines

• Platelet-rich plasma (PRP): in a double-blind trial of 80 athletes, PRP injections did not speed return to play and did not change reinjury at one year compared with placebo [12]. A review of three trials found no effect [11].
• Anti-inflammatory medicines: the only trial we found in hamstring strains, with 44 patients, found they added no benefit to physical therapy over 7 days [13]. Over-the-counter pain relievers may help with pain [21], but there is no evidence they speed healing. Check with your doctor first if you have heart disease, high blood pressure, kidney disease or a history of ulcers or bleeding [21].
• Ice: recommended for comfort in the first days [19] [20]. The guideline supports treatments to control early pain and swelling only at the expert opinion level [1].

Preventing the next one

The guideline gives its strongest grade to including the Nordic hamstring exercise in a prevention program, along with a warm-up, strengthening and sport-specific work such as high-speed running [1]. In this exercise you kneel while someone holds your ankles, then slowly lower your body forward.

• In a trial of 942 Danish soccer players, teams that added it had 3.8 vs. 13.1 hamstring injuries per 100 player-seasons [14].
• In 579 amateur soccer players, injuries were 0.25 vs. 0.8 per 1,000 hours of play [15].
• A review of 15 studies found programs that include it cut hamstring injuries roughly in half [16]. A later reappraisal using stricter methods found the evidence less certain [17], so the size of the benefit is still debated.

When surgery is needed

Surgery is most often done when the tendon has pulled completely away from the bone, called an avulsion. It is not commonly done for tears within the muscle itself [20]. In a review of 1,530 repairs of the upper hamstring tendon, 84.5% of people returned to sport, at an average of 6.5 months, and early repairs had a quicker return and fewer complications than delayed ones [18]. Rehab after that surgery typically takes at least 6 months [20].

That is why the warning signs matter. An injury very close to the buttock or the knee, or a lot of bruising, can mean the tendon has pulled off the bone and needs to be seen by a specialist [21].

What to do in the first days

For the first 2 to 3 days, the NHS recommends [19]:

• Protecting the leg and resting from exercise
• An ice pack wrapped in a towel for up to 20 minutes every 2 to 3 hours
• An elastic bandage that is snug but not tight, taken off before you sleep
• Keeping your leg raised on a pillow when you can
• Avoiding heat, massage and alcohol for the first 3 days

Once the pain allows, start moving gently so the muscle does not stiffen, and get a plan before you return to running or sport [19] [21].

Get medical help promptly if the pain is severe or getting worse, there is a lot of swelling or bruising or it is spreading, it hurts to walk or stand on the leg, the leg is very stiff, or it is not getting better with self-care [19]. The same goes for sudden numbness or tingling [21], or a high temperature with chills, which can be a sign of infection [19].

The takeaway

• Most hamstring strains heal in days to weeks, but injuries near the tendon or from slow overstretching can take months.
• A progressive program with lengthening exercises, agility and trunk work is the best-supported rehab.
• Reinjury is common, especially in the first 2 months back, so finish your rehab.
• PRP injections have not been shown to help, and anti-inflammatories do not speed healing.
• A pop with major bruising near the buttock or knee needs prompt evaluation.

You can start physical therapy in Utah without a referral. If you pulled a hamstring, an evaluation can estimate your timeline and build a program that gets you back to your sport and helps keep you there.