RELATIONSHIP BETWEEN PHYSIOLOGICAL PARAMETERS AND TIME TRIAL PERFORMANCE OVER 1, 2 AND 3 KM IN WELL- TRAINED RUNNERS

INTRODUCTION: Middle distance running is unique due to its proximity to sprint running. Athletes competing over these distance display various physiological profiles [1]. Due to increasing anaerobic energy supply and altered muscular demands of high velocity running, differ- ences become more pronounced with distances bordering sprint events [2]. Previous research has focused on comparing physiological measures in different groups of athletes specialized in distinct running distances [3]. However, within-group comparisons of athletes partic- ipating over various distances are rare. Therefore, it was the aim of this study to assess the relationship of physiological variables and running performance over 1-, 2- and 3-km time-trials (TT) close to the sprint-endurance divide in a single cohort of athletes.

METHODS: Twenty well-trained male sprinters, middle- and long-distance runners/triathletes performed several laboratory tests (incre- mental test, ramp test, sprint test, constant load tests) to determine VO2max, running economy (RE), fractional utilization of VO2max at maximal lactate steady-state (%VO2max), maximal fat oxidation (MFO) and maximal lactate accumulation rate (VLamax) [4]. As perfor- mance tests, TT over 1, 2, and 3-km were performed on an outdoor track. Relationships between physiological parameters and TT velocity as well as 100-m performance (v100) were assessed by correlation coefficients and confidence intervals (CI).

RESULTS: Participants completed the 100-m and 1-, 2-, and 3-km TT in 12.8 ± 0.8, 173.0 ± 10.6, 383.9 ± 24.7 and 606.0 ± 45.5 seconds, respectively. VO2max showed the highest positive relationship with performance over all TT distances (p < 0.001) from 1 to 3 km (r = 0.66, r = 0.80, r = 0.84, respectively), while no significant correlation was present with v100 (r = -0.03, p = 0.90). Despite overall lower correlation coefficient and broader CI, MFO showed similar results. VLamax and RE were positively correlated with v100 and displayed increasingly negative correlation for TT, whereas no significant correlation was found for 1000-m. %VO2max was not significantly correlated with TT nor v100.

CONCLUSION: In line with previous research, aerobically determined variables become increasingly relevant with growing running distance [1]. In contrast, anaerobic power expressed as VLamax, has increasingly negative influence on competitions exceeding ~3 min. Hence, running durations of 1.5-3 min seem to represent the divide of sprint and endurance running . Based on these results, practitioners should focus on enhancement of aerobic measures even for distances close to the sprint-endurance divide. Training emphasizing anaerobic power should be progressively reduced with increasing competition duration due to growing negative influence of anaerobic metabolism.

REFERENCES:
1) Haugen et al. (2021) Sports Med
2) Gastin (2001) Sports Med
3) Svedenhag & Sjödin (1984) Int J Sports Med
4) Quittmann et al. (2020) J Sci Med Sport