Hamstring Strains in BC Soccer and Rugby: Nordic Curls, the L-Protocol, and What the Evidence Supports

Quick answer. Hamstring strains are the single most common time-loss injury in soccer and rugby. They have one of the highest reinjury rates in sports medicine — often above 15% within the first 12 months in published cohorts. Two evidence-supported rehab pathways change both the return-to-sport time and the reinjury rate: the Nordic hamstring program (eccentric lowering of body weight twice a week) and the Askling L-protocol (three specific lengthening exercises). Both outperform generic stretching, isometric work, and rest-based return decisions. The protective benefit depends on continuing the eccentric work after return-to-play and on returning on objective testing, not on days off the field.

If you play recreational or competitive soccer or rugby on the North Shore — North Shore United, Capilano Rugby, the West Vancouver Field Hockey league, or a Burnaby Heights pickup — and you have a recurring hamstring grumble, this article describes the program structure we use at our clinic.

Why hamstring strains keep coming back

The reinjury rate is the problem. The Ekstrand et al. UEFA injury studies in professional football show a hamstring reinjury rate well above other muscle injuries, with most reinjuries occurring within the first two months of return-to-play. The recreational picture is similar. Two drivers explain most recurrences:

• Time-based return decisions. "It's been three weeks, I feel fine, I'm playing Saturday." Symptoms ease before tissue capacity recovers. The same sprint that caused the first strain causes the second.
• Eccentric strength deficits at return. The hamstring is most vulnerable during the late swing phase of sprinting, when the muscle is lengthening eccentrically to decelerate the lower leg. Eccentric strength is the specific quality that protects against this — and it is the specific quality that fades fastest with rest and is slowest to rebuild without targeted programming.

A rehab that does not measure eccentric strength at return and does not include eccentric loading is incomplete.

The Nordic hamstring program — what it is and why it works

The Nordic curl is a knee-flexion exercise performed by kneeling, anchoring the ankles, and slowly lowering the torso forward against gravity, resisting the descent with the hamstrings. The lowering phase is the active ingredient — it is a maximal eccentric contraction at long muscle length.

The Petersen et al. trial in the American Journal of Sports Medicine tested a 10-week Nordic program in over 900 male soccer players. The protocol cut new hamstring injuries by approximately 60% and recurrence by approximately 70% compared with a control group doing standard warm-up. The BJSM systematic review by van Dyk et al. confirmed the effect across multiple subsequent studies.

The dose used in published protocols:

• Week 1: 1 session, 2 sets of 5 reps.
• Weeks 2 to 3: 2 sessions per week, building to 3 sets of 6 to 8 reps.
• Weeks 4 to 10: 3 sessions per week, 3 sets of 8 to 12 reps with controlled tempo.
• Post-week 10 maintenance: 1 to 2 sessions per week to retain the effect.

Initial soreness is real. The first two weeks produce significant delayed-onset muscle soreness, which fades by week 3 to 4. Players who push through the initial soreness with reduced sport volume that week typically tolerate the rest of the program well.

The Askling L-protocol — when end-range control matters

The Askling et al. trial in the BJSM compared two rehab protocols in elite Swedish athletes with acute hamstring strain. One protocol used conventional exercises focused on the muscle midrange. The other (the L-protocol) used three specific exercises emphasizing the lengthened position of the hamstring at end range:

• The Extender — lying supine, the patient slowly straightens the knee at the hip-flexed position to load the hamstring at long length.
• The Diver — single-leg standing, hinging forward at the hip to a near-horizontal trunk position with the rear leg extended.
• The Glider — supine on a wheeled surface, sliding the heel away to load the hamstring at extended position.

The L-protocol group returned to sport faster (median 28 days vs 51 days) without an increase in reinjury rate. The mechanism is thought to be specific adaptation of the hamstring at the muscle lengths where injury actually occurs — the late swing phase of sprinting.

In our clinic, the L-protocol is the early-phase rehab pathway for most hamstring strains, with the Nordic program layered in once the patient tolerates eccentric loading.

How we sequence the rehab phases

A typical 6-to-10-week plan in our practice:

• Week 1 to 2 — acute phase. Pain control, gentle activation, walking, range-of-motion within tolerance. The PEACE & LOVE framework describes the early-acute principles we use.
• Week 2 to 4 — Askling L-protocol. Daily exercise prescription, progressive end-range loading, isometric and slow eccentric work.
• Week 4 to 6 — Nordic program build. Adding eccentric Nordic curls to the L-protocol, progressing speed and volume in lower-limb running.
• Week 6 to 8 — sport reintroduction. Sport-specific running mechanics, sprint progression, change-of-direction drills, controlled match-volume exposure.
• Week 8 to 10 — return-to-play decision. Objective testing — isokinetic or handheld strength, sprint time symmetry, single-leg hop symmetry, full-intensity sport session tolerance — drives the return-to-play call.

The plan is patient-specific and tissue-specific. A grade-I mid-belly strain in a recreational midfielder progresses faster than a grade-II proximal strain in a competitive rugby winger.

The return-to-play criteria we use

The criteria-based return-to-sport post covers our general framework. For hamstrings specifically, the benchmarks before clearing for match play:

• Less than 10% side-to-side eccentric strength deficit on handheld dynamometry or isokinetic testing.
• Pain-free maximal sprinting at full distance.
• Single-leg hop symmetry within 90% of the uninvolved side.
• Completed full-intensity sport-specific training session within the last 5 to 7 days.
• No symptom flare in the 24 hours after that session.

A player who has been off for 6 weeks, feels fine, and has not yet sprinted at full intensity is not ready to play a match. The fail point in most reinjury cases is precisely this — the final intensity step is skipped.

In-season hamstring programming for North Shore amateur teams

The most effective recurrence-prevention measure is to integrate Nordic-style loading into the pre-season and in-season program before the first injury — not after. A practical structure for a recreational soccer or rugby team:

• Pre-season (4 to 6 weeks before first match): 2 Nordic sessions per week alongside regular training.
• In-season: 1 Nordic session per week as part of the pre-training warm-up or post-training routine.
• Mid-season camp or break: re-build to 2 sessions per week for 2 weeks to refresh the eccentric capacity.

The cost is 10 to 15 minutes twice a week. The published benefit in soccer cohorts is a roughly 60% reduction in new strains. Few interventions in sports medicine carry that ratio.

What a hamstring strain visit looks like at Medstar

A 60-minute initial assessment with a sport physiotherapist covering:

• A grading of the strain (I, II, III) based on examination, with imaging considered only for proximal or atypical presentations.
• A phase-appropriate exercise prescription — typically the Askling L-protocol for early phase, progressing to Nordic loading.
• A running and sprinting reintroduction plan.
• A criteria-based return-to-play discussion — not a calendar.
• A maintenance program for after the all-clear, because dropping the eccentric work is the most common reinjury driver.

The strongest outcomes happen when the player commits to the eccentric loading both during rehab and after return to sport. The hamstring is one of the few tissues where prevention work and rehab work are nearly identical — the same Nordic curl that rebuilt the injured side keeps the contralateral side from being next.

This article is general education about hamstring strain rehabilitation. It is not personal medical advice. A regulated practitioner can confirm grade, screen for proximal involvement, and tailor the loading dose to your tissue, history, and sport.

Sources

• Petersen et al. — Preventive effect of eccentric training on acute hamstring injuries in men's soccer, American Journal of Sports Medicine
• Askling et al. — Acute hamstring injuries in Swedish elite sprinters and jumpers: a prospective randomised controlled clinical trial comparing two rehabilitation protocols, BJSM
• van Dyk et al. — Including the Nordic hamstring exercise in injury prevention programmes halves the rate of hamstring injuries, BJSM
• Ekstrand et al. — Injury incidence and injury patterns in professional football: the UEFA injury study, BJSM
• College of Physical Therapists of BC (CPTBC)