Effects of static and PNF stretching on joint position sense and range of motion after a fatigue protocol in male soccer

BACKGROUND: The aim of this study was to compare the effects of a single bout of static stretching (SS) or proprio-ceptive neuromuscular facilitation (PNF) stretching of the knee flexors on joint position sense (JPS) and knee extension range of motion (ROM) after a soccer-specific fatigue protocol in young male professional soccer players. METHODS: Forty-five male soccer players were randomly assigned into three groups: SS, PNF, and control groups (with 15 players in each group). All participants were measured at baseline, 15 min, and 24 h after Bangsbo's fatigue protocol. Participants in the SS and PNF groups performed bilateral stretching of the hamstrings for 2.5 min each side, while the control group had a 5-min rest. The JPS and ROM were measured using digital photography and a goniometer, respectively. RESULTS: A significantly lower JPS error was detected in the PNF group compared with the control group, at both time points (15 min [d=1.19] and 24 hours (d=1.57)). ROM increased in the control, SS, and PNF groups by 2.4%, 2.7%, and 3.4% (P < 0.001), respectively, 15 min (but not 24 hours) after the intervention. CONCLUSIONS: Performing PNF stretching could be a useful way to recover proprioception after muscle fatigue. Hence, to counteract injuries (i.e., JPS error), coaches and therapists should emphasize the use of the PNF stretching technique, rather than SS.