Blood Lactate Responses of Male and Female Players Across an International Rugby Sevens Tournament

This study investigated within- and between-matches blood lactate (La-) responses across an international Rugby Sevens tournament (5 matches over 2 d) in male and female players.

Earlobe blood samples were taken from 25 professional players around matches: before warm-up (PRE), immediately upon finishing match participation (POST), and 30 minutes postmatch (30 min).

POST [La-] (mean [SD], range) for males was 10.3 (3.2; 2.9-20.2) mmol·L-1 and for females was 9.1 (2.3; 3.4-14.6) mmol·L-1. Linear mixed-effects models revealed a decrease in POST [La-] after match 5, compared to match 1. Increased PRE [La-] was found before match 2 (+0.8 [0.6-1.1] mmol·L-1), match 3 (+0.8 [0.5-1.1] mmol·L-1), and match 5 (+0.6 [0.4-0.9] mmol·L-1) compared to match 1 (all P < .001). The [La-] remained elevated at 30 min, compared to PRE (+1.7 [1.4-2.0] mmol·L-1, P < .001), with ∼20% of values persisting >4 mmol·L-1. Higher POST was observed in males compared to females (+1.6 [0.1-3.2] mmol·L-1, P = .042); however, no differences between sexes were found across 30 min or PRE [La-]. No [La-] differences between positions (backs and forwards) were identified.

Lactate concentrations above 10 mmol·L-1 are required to effectively simulate the anaerobic demands of international Rugby Sevens matches. Practitioners are advised to individualize anaerobic training prescription due to the substantial variability observed within positional groups. Additionally, improving athletes' metabolic recovery capacity through training, nutrition, and recovery interventions may enhance physical preparation for subsequent matches within a day, where incomplete lactate clearance was observed.