Effect of training load distribution on aerobic fitness measures in hurling players

The aim of the current investigation was to quantify the training intensity distribution of hurling players and their association with changes in aerobic fitness measures within hurling players. Thirty hurling players (n = 30; age 26.5 ± 3.2 years; height 178.9 ± 3.2 cm; body mass 81.5 ± 4.5 kg) were observed during the pre-championship training period (12 weeks). Aerobic fitness measures (VO₂max), peak treadmill velocity (km·h^-1), heart rates (HRs) at 2 and 4 mmol·L^-1 blood lactate concentrations, and Yo-Yo intermittent recovery test performance (Yo-YoIR1) were assessed before and after the training period. Training intensities were categorized using 3 individualized HR zones based on the following criteria: low intensity (≤HR 2 mmol·L^-1), moderate intensity (between HR 2 and 4 mmol·L^-1), and high intensity (≥HR 4 mmol·L^-1). Analysis of 1,025 individual training sessions showed that players spent 58.1 ± 2.5%, 24.3 ± 2.9%, and 17.6 ± 1.3% of time in the low-, moderate-, and high-intensity zones, respectively. The training time spent at high intensity (Zone 3) showed moderate-to-large associations with improvements in S2 (r = 0.80; p = 0.04) and S4 (r = 0.58; p = 0.03). Similar trends were observed for time spent in high intensity and improvements in VO₂max (r = 0.77; p = 0.001) and Yo-YoIR1 performance (r = 0.65; p = 0.05). Hurling players have been shown to spend the majority of training time in low (≤ HR 2 mmol·L^-1) to moderate intensity (between HR 2 and 4 mmol·L^-1) training. However, only the time spent at high intensity (≥90% of maximal HR) was related to changes in aerobic fitness. These results support the usefulness of the quantification of aerobic training load using HR. The study also supports the efficacy of spending elements of training time within the high-intensity zone to increase hurling player’s aerobic fitness characteristics.