Comparative effectiveness of rehabilitation protocols for hamstring injuries: A systematic review and meta-analysis.

Hamstring strains are common in sports with high-speed movements and tend to recur, so finding which rehabilitation approach best supports recovery and prevents reinjury matters for athletes and clinicians alike. This review pooled results from nine randomized controlled trials comparing different protocols, including eccentric exercises like Nordic hamstring training, stretching, strength-focused C-protocol, eccentric-loading L-protocol, cryotherapy, and the FUNBALL program. Overall, eccentric-based approaches, particularly the L-protocol, were linked to fewer reinjuries and quicker return to play compared with standard strength training, while FUNBALL showed strength gains and pain-free approaches outperformed cryotherapy on injury duration and recurrence. These patterns are interesting because they point toward lengthening-type exercises as a promising direction for rehabilitation, but the evidence rests on a small number of studies with mostly male participants and varied protocols, so the findings should be read as suggestive rather than definitive guidance for practice.

If you've ever pulled a hamstring during sprinting or sports, you know how frustrating it can be when it keeps coming back. This review looked at several small clinical trials testing different recovery approaches, including exercises that lengthen the muscle under tension (like Nordic hamstring exercises), stretching, strength training, cryotherapy (cold therapy), and a specific exercise program called FUNBALL. The researchers found that an eccentric-loading approach was linked to fewer repeat injuries and a faster return to play compared with standard strength training, and pain-free approaches like stretching and eccentric work seemed to outperform cryotherapy in reducing how long injuries lasted and how often they came back.

The FUNBALL program was associated with improved muscle strength measures. It's worth knowing that this evidence comes from a small number of trials, mostly involving men, using different protocols that make direct comparisons tricky. So while these patterns are encouraging, they aren't yet strong enough to be considered settled answers for everyone recovering from a hamstring strain.

This is a summary of research, not medical advice. Talk to your own healthcare provider about anything affecting your care.

This review addresses a recurring clinical question: among the various hamstring rehabilitation protocols in use, is there evidence that one approach outperforms another for recovery time, strength, and reinjury risk. Drawing on nine randomized controlled trials assessed with the Cochrane ROB2 tool, the authors pooled data comparing eccentric training (including Nordic hamstring exercises), stretching, the C-protocol (strength training), the L-protocol (eccentric loading), cryotherapy, and the FUNBALL program. The headline finding is that the L-protocol was associated with a statistically significant reduction in reinjury rate and faster return to play compared with the C-protocol, suggesting eccentric lengthening work may have a specific role beyond general strengthening, though this rests on pooled data from a small set of trials with protocol heterogeneity.

FUNBALL's association with improved maximal eccentric force and knee flexor strength is a secondary strength outcome and does not itself confirm reduced injury incidence. The comparison favoring pain-free rehabilitation over cryotherapy also informs expectations around recovery duration rather than establishing definitive superiority.

Limitations that affect applicability include the small number of included trials, male-predominant samples, heterogeneous protocols, and exclusion of non-English studies, meaning these findings should inform rather than dictate protocol selection, and gender-specific and coordination-related questions remain unaddressed.