DETERMINANTS OF PHYSICAL PERFORMANCE AND PHYSIOLOGICAL RESPONSES DURING AN OFFICIAL CROSS-COUNTRY MARATHON OF MOUNTAIN-BIKING (XCM-MTB)

Abstract:

Introduction: the variable determinants of physical performance in a cross-country marathon of mountain biking (XCM-MTB) are still unknown. Objective: we aimed to verify the training control variables and the physiological responses in an official XCM-MTB race. Material and methods: Thirteen athletes (11 men and 2 women; 33.3 ± 12.7 years of age) participated in this study. The study was conducted during an official XCM-MTB in Brazil (route of 70 km). The heart rate (HR), altimetry, velocity, temperature, pacing, and power were obtained every 10 km travelled by the STRAVA application. Multivariate linear analysis was performed to verify whether the variables could predict physical performance. Results: the athletes maintained constant HR elevation in the corresponding zone 80% HRmax. The athletes also presented a variation in the pacing (F = 35.82; p < 0.001; d = 0.66) and power (F = 7.20; p < 0.001; d = 0.18) presenting higher values in the last ten kilometers. Only pacing can be considered a predictor of the physical performance (β = 0.958; t = 7.30; p < 0.001), specifically the pacing at 20km (F = 10.23; p = 0.004; R2 = 0.82) can be considered as a predictor of the total time. Conclusion: the study concluded that the analysed variables are reliable for training control in an official XCM - MTB race. HR and power are variables that can be used to prescribe training, as they change according to the requirements of the race. Power can also be used as a performance predictor as it is directly influenced by terrain.