Pacing analysis and comparison of TOP-10 and NOT TOP-10 Ultra Trail Cape Town 100-km finishers.

Background: Pacing strategies during endurance efforts vary depending on athlete experience, race length, and terrain. In ultramarathon trail running the specific race route profile can have a significant impact on optimal pacing strategy. The aim of this study was to determine the relationship between uphill, downhill and level running with overall performance and to compare the difference in pacing strategies between top 10 (TOP-10) and non-top 10 (NOT TOP-10) finishers of a 100-km ultra-trail marathon with +5000-m elevation gain.

Methods: Fifty male finishers (TOP-10: N.=6, NOT TOP-10, N.=44) and forty-six individual segments (1.5±1.2 km) were analyzed based on 2021 100-km UTCT STRAVA data. Relative segment speed and CV% were used to identify pacing strategies. Spearman Rank and Mann-Whitney U Tests were used to analyze the data. Significance was set at P<0.05.

Results: Uphill running had the strongest relationship with overall performance (r=0.826, P<0.01). Substantially weaker relationships between overall running performance and level (r=0.402, P<0.01) and downhill (r=-0.382, P<0.01) running performance were found. The CV% was significantly lower in TOP-10 (32.10±1.81) than NOT TOP-10 (35.39±4.43) (U=24, r=0.46, P<0.01).

Conclusions: Uphill running performance remains a valuable measure of overall trail running performance as it represents a higher percentage of overall running demand. TOP-10 runners have diminished decay in initial running speed than NOT TOP-10 runners, despite a generally high variation in pace and net positive split in ultra-trail running.