Whether age-related differences in blood lactate concentrations (BLC) reflect specific BLC kinetics was analyzed in 15 prepubescent boys (age 12.0 ± 0.6 yr, height 1.54 ± 0.06 m, body mass 40.0 ± 5.2 kg), 12 adolescents (16.3 ± 0.7 yr, 1.83 ± 0.07 m, 68.2 ± 7.5 kg), and 12 adults (27.2 ± 4.5 yr, 1.83 ± 0.06 m, 81.6 ± 6.9 kg) by use of a biexponential four-parameter kinetics model under Wingate Anaerobic Test conditions. The model predicts the lactate generated in the extravasal compartment (A), invasion ( k1), and evasion ( k2) of lactate into and out of the blood compartment, the BLC maximum (BLCmax), and corresponding time (TBLCmax). BLCmax and TBLCmax were lower ( P < 0.05) in boys (BLCmax 10.2 ± 1.3 mmol/l, TBLCmax 4.1 ± 0.4 min) than in adolescents (12.7 ± 1.0 mmol/l, 5.5 ± 0.7 min) and adults (13.7 ± 1.4 mmol/l, 5.7 ± 1.1 min). No differences were found in A related to the muscle mass (AMM) and k1 between boys (AMM: 22.8 ± 2.7 mmol/l, k1: 0.865 ± 0.115 min−1), adolescents (22.7 ± 1.3 mmol/l, 0.692 ± 0.221 min−1), and adults (24.7 ± 2.8 mmol/l, 0.687 ± 0.287 min−1). The k2 was higher ( P < 0.01) in boys (2.87 10−2 ± 0.75 10−2 min−1) than in adolescents (2.03 × 10−2 ± 0.89 × 10−2 min−1) and adults (1.99 × 10−2 ± 0.93 × 10−2 min−1). Age-related differences in the BLC kinetics are unlikely to reflect differences in muscular lactate or lactate invasion but partly faster elimination out of the blood compartment.
The Wingate Anaerobic Test, a Narrative Review of the Protocol Variables That Affect the Results Obtained