(52) ASSOCIATION OF THIGH PRESSURE PAIN THRESHOLD WITH TIME TO EXHAUSTION IN CYCLING AMONG WOMEN

Purpose: This study examined the relationship between heat and pressure pain thresholds and aerobic performance, specifically time to exhaustion (TTE), during a graded exercise test (GXT) on a cycle ergometer. Methods: Healthy, recreationally active female participants (n = 13; age = 21.46 ± 2.67 years; height = 166.31 ± 6.76 cm; weight = 66.27 ± 13.17 kg; VO₂ peak = 27.31 ± 5.22 ml/kg/min; no known cardiovascular or metabolic disease) completed pain threshold tests before doing a GXT on a cycle ergometer. At the same time, peak oxygen consumption rate (VO₂ peak), peak power output (PPO), and time to exhaustion (TTE) were measured. All tests were performed under standardized laboratory conditions (22°C, 45% relative humidity, between 0800–1300). Pain thresholds were assessed using heat pain threshold (HPT) and pressure pain threshold (PPT) tests, with stimuli applied twice to the dominant forearm (FA) and thigh (TH); the two measurements were then averaged for analysis. For each test, the stimulus intensity increased until participants said 'stop' upon first perceiving pain. The GXT started at 50 W and increased by 25 W every two minutes until volitional fatigue. Stepwise regression was used to identify significant predictors of TTE, including PPT FA, PPT TH, HPT FA, and HPT TH, with an a priori alpha level of p < 0.05. Results: Stepwise regression identified PPT TH as the only significant predictor of TTE (β = 0.0065, p = 0.0004), indicating that a 1-unit increase in PPT TH is associated with a 0.0065-minute (approximately 0.39-second) increase in TTE. This indicated that a 1-unit increase in PPT TH is associated with a 0.0065-minute increase in TTE. Notably, PPT TH accounted for 35.7% of the variability in TTE. PPT FA and all HPT measurements did not show significant interactions. Conclusions: The pressure pain threshold at the thigh is a significant predictor of endurance performance during a cycling test. However, additional factors, such as sleep or nutrition may also influence TTE and should be considered in future research. Practical Applications: These findings suggest a potential link between localized pain perception and muscle endurance capacity. Future investigations could explore these pain thresholds in more detail to inform training protocols and pain management strategies in athletic and clinical settings. Acknowledgements: None