Author(s): ALDA-BLANCO, A., RODRÍGUEZ-BARBERO, S., MUÑOZ DE LA CRUZ, V., VALERO, F., GONZÁLEZ-MOHÍNO, F., Institution: UNIVERSIDAD DE CASTILLA LA MANCHA, Country: SPAIN, Abstract-ID: 1090

INTRODUCTION:
Performance in long-distance events is influenced by several key physiological factors, including maximum oxygen uptake (VO₂max), running economy (RE), and the percentage of VO₂max at which the aerobic and anaerobic thresholds occurred [1]. Previous studies found differences in aspects such as the percentage of VO₂max where lactate threshold occurs between different level runners [2]. Therefore, this intervention aimed to analyze physiological differences between performance levels to better understand their influences on key performance parameters in long-distance runners.

METHODS:
Thirty-four male and 22 female runners were categorized into two groups based on the 50th percentile of WA scores from 5 km to half-marathon events. Group 1 included runners with 965.18 ± 67.14 points for females and 933.06 ± 40.82 points for males. Group 2 averaged 652.55 ± 134.15 points for females and 737.41 ± 109.88 points for males.

A maximal graded exercise test on a treadmill (HP Cosmos Pulsar, Germany) was performed, starting at 10 km·h⁻¹ for females and 12 km·h⁻¹ for males, increasing by 1 km·h⁻¹ per minute until exhaustion and at 1% of inclination. Respiratory variables were measured with a gas analyzer (CPX Ultima MedGraphics, United States), and heart rate (HR) was recorded using a Polar H10 monitor. Ventilatory thresholds (VT1, VT2), VO₂max, and maximal aerobic speed (MAS) were determined. Independent t-tests were conducted separately for males and females to compare performance groups.

RESULTS:
At the VT1, significant differences between groups were found in speed (p<0.001), %MAS where VT1 occurs (p=0.019), HR (p=0.01), and RPE (p=0.016) for male participants. In contrast, for female participants, there were only significant differences between groups in the speed (p=0.008).
At the VT2, significant differences between groups were observed in speed (p=0.022) and HR (p=0.03) for male participants. For female participants, there were significant differences in speed (p<0.001) and VO₂ (ml/kg/min) (p=0.018).

CONCLUSION:
Male and female runners with higher performance levels demonstrated higher absolute speeds at both VT1 and VT2, as well as a higher %MAS where VT1 occurs only in male runners. Additionally, HR and RPE were significantly higher in males with a higher performance level, which may be attributed to their ability to sustain greater relative intensity over the same duration. These findings highlight the importance of stratifying athletes by performance level when analyzing physiological responses.

REFERENCES
1. Joyner, M.J. Modeling: optimal marathon performance on the basis of physiological factors. J Appl Physiol (1985) 1991, 70, 683-687, doi:10.1152/jappl.1991.70.2.683.
2. Støa, E.M.; Helgerud, J.; Rønnestad, B.R.; Hansen, J.; Ellefsen, S.; Støren, Ø. Factors Influencing Running Velocity at Lactate Threshold in Male and Female Runners at Different Levels of Performance. Front Physiol 2020, 11, 585267, doi:10.3389/fphys.2020.585267.