Abstract:
The aim of this study was to examine heart rate, blood lactate concentration and estimated energy expenditure
during a competitive rugby league match. Seventeen well-trained rugby league players (age, 23.9±4.1 years;
VO2max, 57.9±3.6 ml·kg-I·min-\ height, 1.82±0.06 m; body mass, 90.2±9.6 kg; mean±s) participated in
the study. Heart rate was recorded continuously throughout the match using Polar Vantage NV recordable heart
rate monitors. Blood lactate samples (n= 102) were taken before the match, after the warm-up, at random
stoppages in play, at half time and immediately after the match. Estimated energy expenditure during the match
was calculated from the heart rate- VO2 relationship determined in laboratory tests. The mean team heart rate
(n = 15) was not significantly different between halves (167 ± 9 vs 165 ± 11 beats. min -I). Mean match intensity
was 81.1 ± 5.8% VO2max' Mean match blood lactate concentration was 7.2 ± 2.5 mmol 1-1, with concentrations
for the first half (8.4± 1.8 mmol-1-1) being significantly higher than those for the second half
(5.9±2.5 mmol-l-1) (P<0.05). Energy expenditure was approximately 7.9 MJ. These results demonstrate
that semi-professional rugby league is a highly aerobic game with a considerable anaerobic component requiring
high lactate tolerance. Training programmes should reflect these demands placed on players during competitive
match-play.
