ECSS Paris 2023: OP-AP35
INTRODUCTION: Trail running (TR) has grown exponentially in recent years, increasing interest in its performance factors (Babí-Lladós et al., 2021). Strength is crucial for these athletes, especially on uneven terrain (Ehrström et al., 2018), and the Force-Velocity Profile (FVP) is a useful tool to assess neuromuscular balance and its impact on performance (Pastor et al., 2022). This study analyzed the FVP in trail runners, as well as their body composition and vertical jump ability, identifying common patterns and optimization strategies. METHODS: A total of 17 trail runners (6 female and 11 male) with at least two years of experience were evaluated. Body composition was assessed using bioelectrical impedance (InBody 770), jump ability with the Bosco Test, and FVP through countermovement jumps (CMJ) with progressive loads (0, 10, 20, and 30% of body weight) on a force platform (Hawkin Dynamics). Theoretical maximum force (F0), theoretical maximum velocity (V0), maximum power (Pmáx), and the imbalance between force and velocity (FVimb) were calculated. RESULTS: Results showed differences in body composition, with a body fat percentage of 10.17 ± 2.92% in male and 17.25 ± 3.95% in female. In the Bosco Test, male achieved greater jump heights in SJ (28.64 ± 4.90 cm), CMJ (32.58 ± 5.24 cm), and DJ (32.91 ± 6.19 cm) compared to female (23.48 ± 5.81 cm, 26.28 ± 6.53 cm, and 27.02 ± 5.00 cm, respectively). In PFV, all runners showed an imbalance with a force deficit (FVimb <100%), with mean F0 values of 28.35 ± 3.79 N/kg in male and 24.73 ± 4.37 N/kg in female, while V0 was slightly higher in female (5.25 ± 2.22 m/s) compared to male (4.90 ± 1.61 m/s). The mean Pmáx was 35.16 ± 11.93 W/kg in male and 30.79 ± 8.62 W/kg in female. CONCLUSION: The most relevant finding was the generalized imbalance in FVP, with a tendency towards a force deficit. This suggests the need to incorporate specific strength training to optimize TR performance. Evaluating FVP may be key to individualizing training programs and improving physical preparation in this sport. Future research should focus on the application of strength interventions and their impact on performance improvement. REFERENCES: Babí-Lladós, J., Soler-Prat, S., Inglés-Yuba, E., & Labrador-Roca, V. (2021). History and planning process of trail races in Spain. RICYDE: Revista Internacional de Ciencias del Deporte, 17(64), 140-159. DOI: 10.5232/RICYDE2021.06403 Ehrström, S., Tartaruga, M., Easthope, C., Brisswalter, J., Morin, J., & Vercruyssen, F. (2018). Short Trail Running race: beyond the classic model for endurance running performance. Medicine and Science in Sports and Exercise, 50(3), 580-588. DOI:10.1249/MSS.0000000000001467 Pastor, F., Besson, T., Varesco, G., Parent, A., Fanget, M., Koral, J., Foschia, C., Rupp, T., Rimaud, D., Féasson, L., & Millet, G. Y. (2022). Performance determinants in Trail-Running races of different distances. International Journal of Sports Physiology and Performance, 17(6), 844-851. DOI: 10.1123/ijspp.2021-0362
Read CV Fabio García-HerasECSS Paris 2023: OP-AP35
INTRODUCTION: Mountain running races take place on predefined routes in mountainous terrain, requiring athletes to navigate steep elevations, varied surfaces, and changing weather conditions while optimizing speed and endurance [1]. Heart rate (HR) has traditionally been used to monitor race intensity, though running power has recently emerged as a valuable metric [2]. While previous research has primarily focused on male athletes, competition demands for female runners remain unclear. This study aims to examine sex-based differences in external and internal load during mountain running competitions, considering physiological, performance, and biomechanical variables in races ranging from 20 to 45 km. METHODS: Twenty-four trained mountain runners (12 men and 12 women) with over four years of experience participated in the study. They trained approximately five days per week, accumulating 5 to 12 hours of training. Body fat percentage was assessed via bioelectrical impedance, and a graded treadmill test was conducted to determine maximal HR and VO2max. Runners competed in two 20-45 km races while wearing GPS and Stryd devices to record HR and running power data. Post-race, rate of perceived exertion (RPE) was collected. Data were analyzed using GoldenCheetah to determine exercise intensity distribution and external/internal load. RESULTS: Men exhibited significantly higher VO2max, maximal workload, and speeds at ventilatory thresholds (P<0.01), as well as a lower body fat percentage (P<0.01). Women completed races in significantly longer times (31%, P<0.01) and placed lower overall (P<0.001), though no significant differences were observed in relative rankings within each sex. At the same relative intensity, men produced greater running power, resulting in lower RPE/power and %HRmax/power ratios (P<0.01). Men also displayed higher maximal mean power and spent more time at higher power intensities(P<0.01), while women accumulated more time in the 1-3 W/kg power range(P<0.01). External load was higher in men(P<0.01), whereas internal load (assessed via RPE and HR) was similar or lower(P<0.05). Biomechanically, men demonstrated higher cadence, form power, and stiffness (P<0.05), whereas women exhibited longer ground contact times and greater form power relative to running power (P<0.05). CONCLUSION: This study highlights key physiological, performance, and biomechanical differences between male and female mountain runners. Men exhibit higher maximal power output and external load, while women show distinct intensity distribution and biomechanical patterns. These findings underscore the importance of running power and biomechanics in understanding sex-based performance differences in mountain running. REFERENCES 1. Scheer et al. (2020) 2. Rodríguez-Medina et al. (2024)
Read CV Rodríguez Medina JuanECSS Paris 2023: OP-AP35
INTRODUCTION: Trail runners develop biomechanical and neuromuscular adaptations to improve performance and reduce muscle damage due to the sport’s demands. Key factors include speed, ground contact time (GCT), cadence, and leg stiffness. Shorter GCT and increased leg stiffness enhance elastic energy return, with both reflecting the stretch-shortening cycle (SSC), crucial for running efficiency. Strength, particularly knee extensor strength and Achilles tendon adaptations, is essential for trail running performance. However, the impact of different resistance training loads on performance remains unclear, especially regarding how varying loads affect elastic energy utilization and force production in prolonged versus short efforts. This study aimed to assess the relationship between biomechanical and strength variables at various 1RM percentages in highly trained male trail runners. METHODS: Fifteen internationally competitive, injury-free trail runners participated in this study. To estimate their one-repetition maximum (1RM) in the half-squat, participants performed the exercise on a Smith Machine. Mean propulsive velocity and peak force were continuously measured at 1,000 Hz using a linear position transducer attached to the barbell. Participants then completed a running session consisting of a 9-minute and a 3-minute run, separated by a 30-minute rest. They refrained from vigorous activity for 24 hours before each test. Spatiotemporal variables and leg stiffness were recorded with a Stryd power meter. RESULTS: Pearson’s correlation analysis identified significant associations between relative load (%1RM) and leg stiffness across different running efforts. Specifically, leg stiffness correlated with loads of 30% (r=0.533) and 40% 1RM (r=0.33) during the 9-min run and with 40% 1RM (r=0.547) during the 3-min run. Regarding SDef, significant correlations were found between SDef at 50%, 60%, and 70% 1RM and leg stiffness during the 9-minute run (r = 0.539, r = 0.560, and r = 0.535, respectively). During the 3-minute run, SDef at 40%, 50%, 60%, and 70% 1RM correlated significantly with GCT (r=-0.559, r=-0.570, r=-0.565, and r=-0.527, respectively). Additionally, leg stiffness was significantly associated with SDef at 60% (r=0.544) and 70% (r=0.525) 1RM. CONCLUSION: Significant correlations between relative training loads (%1RM), leg stiffness, and GCT emphasized the role of the stretch-shortening cycle (SSC) in performance. Moderate loads (30–40% 1RM) influenced leg stiffness during prolonged running, while higher loads (50–70% 1RM) affected both stiffness and GCT in shorter efforts. These findings suggest that resistance training modulates SSC efficiency, impacting elastic energy utilization and force production. Tailoring resistance training loads to enhance stiffness and SSC function may optimize performance in trail running, providing valuable insights for coaches.
Read CV Diego Jaen-CarrilloECSS Paris 2023: OP-AP35