Acute Changes in Quadriceps Flexibility: PNF Versus Static Stretch in Senior Athletes

Background: Flexibility is a crucial component of physical fitness, particularly among senior athletes, as it influences performance, injury prevention, and rehabilitation. The quadriceps muscle plays a pivotal role in functional mobility, and its flexibility can be improved through different stretching techniques. While static stretching is widely used, Proprioceptive Neuromuscular Facilitation (PNF) stretching has been proposed as a more effective method for improving range of motion (ROM). However, limited research exists comparing the acute effects of these two methods in senior athletes. Objective: This study aims to compare the acute effects of PNF stretching and static stretching on quadriceps flexibility in senior athletes. The study evaluates changes in ROM and perceived muscle tightness immediately following stretching interventions. Methods: A randomized controlled trial was conducted with 60 senior athletes (aged 50 years and older). Participants were randomly assigned to either a PNF stretching group or a static stretching group. Quadriceps flexibility was assessed using a goniometer, and muscle tightness was evaluated using the Visual Analog Scale (VAS). The PNF group performed the hold-relax technique, while the static stretching group held a passive stretch for 30 seconds. Pre- and post-intervention measurements were analyzed using paired and independent t-tests. Results: Both groups exhibited significant improvements in ROM and reductions in muscle tightness post-intervention (p < 0.001). However, the PNF group showed a significantly greater increase in ROM (mean improvement: 15.47°) compared to the static stretching group (mean improvement: 7.33°). Similarly, the PNF group experienced a larger reduction in muscle tightness (mean VAS reduction: 2.87) compared to the static stretching group (mean VAS reduction: 1.20). Cohen’s d effect size analysis indicated a large practical significance for both ROM and VAS improvements in the PNF group. Conclusion: The results suggest that PNF stretching is more effective than static stretching in acutely increasing quadriceps flexibility and reducing muscle tightness in senior athletes. These findings support the integration of PNF stretching in athletic training and rehabilitation protocols to optimize performance and prevent musculoskeletal injuries. Future research should explore the long-term effects of PNF stretching on flexibility and functional performance in older adults.