Practical recommendations on stretching exercise: A Delphi consensus statement of international research experts

Background: Stretching has wide appeal, but there seems to exist some mismatch between its purported applications and what the evidence shows. There is compelling evidence for some stretching applications, but for others, the evidence seems heterogeneous or unsupportive. The discrepancies even affect some systematic reviews, possibly due to heterogeneous eligibility criteria and search strategies. This consensus paper seeks to unify the divergent findings on stretching and its implications for both athletic performance and clinical practices by delivering evidence-based recommendations. Methods: A panel of 20 experts with a blend of practical experience and scholarly knowledge was assembled. The panel meticulously reviewed existing systematic reviews, defined key terminologies (e.g., consensus definitions for different stretching modes), and crafted guidelines using a Delphi consensus approach (minimum required agreement: 80%). The analysis focused on 8 topics, including stretching's acute and chronic (long-term) effects on range of motion, strength performance, muscle hypertrophy, stiffness, injury prevention, muscle recovery, posture correction, and cardiovascular health. Results: There was consensus that chronic and acute stretching (a) improves range of motion (although alternatives exist) and (b) reduces muscle stiffness (which may not always be desirable); the panel also agreed that chronic stretching (c) may promote vascular health, but more research is warranted. In contrast, consensus was found that stretch training does not (a) contribute substantively to muscle growth, (b) serve as an all-encompassing injury prevention strategy, (c) improve posture, or (d) acutely enhance post-exercise recovery. Conclusion: These recommendations provide guidance for athletes and practitioners, highlighting research gaps that should be addressed to more comprehensively understand the full scope of stretching effects.