Gill, Nicholas D.Koumandarakis, Nikolas2026-01-232026-01-232025https://hdl.handle.net/10289/17901Heart rate (HR) monitoring provides insight into the demands of rugby union and may be able to help discriminate between different levels of competition. There is limited data examining the differences in physiological responses among different levels of rugby union. Rugby union athletes from different levels of competition (n=15 School, n=15 Club, n=15 Professional, and n=15 International) were included in the study. HR was measured via chest straps worn during the game with specific variables compared between levels of competition (e.g. Average (Avg) HR (bpm), and HR during worst-case scenario (WCS) periods of play (1, 2, 3, 4 and 5 minutes). Data was collected from eight matches for International, six matches for Professional and Club, and with School only able to play four due to season constraints. A one-way ANOVA revealed statistically significant differences in Avg HR across the four competition levels (p < 0.05). School players recorded the highest Avg HR (175 ± 10 bpm), while International players had the lowest (159 ± 9 bpm). Club and Professional teams had similar values, with no significant difference between them (p = 0.72). This trend was consistent across both forwards and backs. WCS HRs over rolling 1–5-minute intervals followed the same pattern, with School players consistently recording the highest values and International players the lowest. The largest WCS difference was observed at the 2-minute interval between School (191 ± 9 bpm) and International (179 ± 6 bpm) teams. Tukey post-hoc tests confirmed that School and International were significantly different from all other groups, while Club and Professional teams did not differ significantly. To the authors knowledge, this study is the first to compare heart rate metrics through different levels of competition in rugby union and is timely as the age of professional players is getting lower. Coaches should consider accurately tailor training to prepare athletes for optimal performance across different levels of competition as HR provides an accurate measure of internal load and could be more effective than the commonly used measures of external load e.g. GPS.enAll items in Research Commons are provided for private study and research purposes and are protected by copyright with all rights reserved unless otherwise indicated.Internal loadexternal loadteam sportscardiovascular responsesThesis