Here's a statistic that should change how every youth soccer program trains: a single exercise, done once or twice per week, can cut hamstring injury rates in half.
That exercise is the Nordic curl. And according to a Cochrane systematic review of randomised controlled trials, it reduces hamstring strain injuries in soccer players by 51%.
Despite this evidence — which has been published in major sports medicine journals for over a decade — most youth soccer programs in the US still don't use them.
Why Hamstrings Are the Most Injured Muscle in Soccer
Hamstring strains are the most common muscle injury in soccer at every level — from youth leagues to the Champions League. They account for roughly 12–16% of all soccer injuries and have one of the highest recurrence rates of any sports injury (around 30% of players who suffer one will re-injure the same muscle).
The mechanics are well understood: hamstrings are most vulnerable at high running speeds during the late swing phase — when the leg is extending forward and the hamstring must rapidly decelerate the limb before foot strike. It's an eccentric (lengthening under load) demand, and one that most conventional hamstring exercises don't train.
What conventional training misses:
The Evidence Base
The research on Nordic curls in soccer is unusually clear:
Hamstring injury incidence in soccer players following a Nordic curl program — Cochrane review of 8 RCTs (van Dyk et al., 2019)
Adductor injury rate when combining Nordic curls with Copenhagen plank — BJSM prospective study in Danish elite soccer
Eccentric hamstring strength in trained vs. untrained soccer players after 8-week Nordic protocol
40m sprint improvement observed in youth athletes after 8-week Nordic + sprint mechanics program — consistent with increased hamstring stiffness and RFD
How to Do a Nordic Curl
Kneel on a padded surface (gym mat, folded towel, or foam pad)
Have a partner hold your ankles firmly to the ground — or hook feet under a barbell, couch, or lat pulldown pad
Keep your body in a straight line from knees to head — don't break at the hips
Slowly lower your body toward the ground by allowing your knees to extend — your hamstrings are the only thing braking the descent
Go as low as you can control. When you reach your limit, catch yourself with your hands
Use your hands to push back up to the start position (the concentric phase is not the training stimulus)
Reset and repeat
The most important warning in this article
If you've never done Nordic curls, start with 2×5 reps MAXIMUM. The eccentric hamstring soreness from your first session is unlike anything else in the gym. Players who jump to 3×10 in their first session commonly can't sprint properly for 5–7 days. This isn't a scare tactic — it's standard guidance in every Nordic curl research protocol. Start conservative.
The 8-Week Beginner Protocol
| Phase | Sets × Reps | Notes |
|---|---|---|
| Week 1–2 | 2 × 5 | Focus purely on the lowering phase. Catch at the bottom, push back up with hands. |
| Week 3–4 | 3 × 6 | Begin controlling the catch position — try to hover above the ground for a moment. |
| Week 5–6 | 3 × 8 | Add a 1-second pause at the lowest controlled point before catching. |
| Week 7–8 | 3 × 10 | Full range, controlled throughout. Start exploring not using hands on the easiest reps. |
| Maintenance | 2 × 8 (1×/week) | In-season maintenance dose — enough to preserve the adaptation without excessive soreness. |
When to Do Them in Your Training Week
- Off-season: 2× per week. At the END of a strength session — never before sprinting or high-velocity work because the soreness risk is too high initially.
- In-season: 1× per week, maintenance dose of 2×8. Done on a non-match day with at least 48 hours before the next game.
- Never the day before a match — the DOMS risk for players new to the exercise is real.
- After 4–6 weeks, most players adapt and the soreness becomes manageable. Timing becomes more flexible.
The bottom line
There is no other single exercise with as much evidence behind it for soccer injury prevention. The investment is 10–15 minutes twice a week. The return is a 50% reduction in the injury most likely to sideline a player for weeks or months. If your youth program isn't doing Nordic curls, it's leaving one of the clearest wins in sports medicine on the table.