DETERMINATION OF MAXIMAL LACTATE STEADY-STATE RESPONSE IN SELECTED SPORTS-EVENTS

Maximal lactate steady state (MLSS) refers to the upper limit of blood lactate concentration indicating an equilibrium between lactate produ ction and lactate elimination during constant workload. The aim of the present study was to investigate whether different levels of MLSS may explain different blood lactate concentration (BLC) levels at submaxi mal workload in the sports events of rowing, cycling, and speed skatin g. Eleven rowers (mean +/- SD, age 20.1 +/- 1.5 yr, height 188.7 +/- 6 .2 cm, weight 82.7 +/- 8.0 kg), 16 cyclists and triathletes (age 23.6 +/- 3.0 yr, height 181.4 +/- 5.6 cm, weight 72.5 +/- 6.2 kg), and 6 sp eed skaters (age 23.3 +/- 6.6 yr, height 179.5 +/- 7.5 cm, weight 73.2 +/- 5.6 kg) performed an incremental load test to determine maximal w orkload and several submaximal 30-min constant workloads for MLSS meas urement on a rowing ergometer, a cycle ergometer, and on a speed-skati ng track. Maximal workload was higher (P less than or equal to 0.05) i n rowing (416.8 +/- 46.2 W) than in cling (358.6 +/- 34.4 W) and speed skating (383.5 +/- 40.9 W). The level of MLSS differed (P less than o r equal to 0.001) in rowing (3.1 +/- 0.5 mmol . l(-1)), cycling (5.4 /- 1.0 mmol . l(-1)), and in speed skating (6.6 +/- 0.9 mmol . l(-1)). MLSS workload was higher (P less than or equal to 0.05) in rowing (31 6.2 +/- 29.9 W) and speed skating (300.5 +/- 43.8 W) than in cycling ( 257.8 +/- 34.6 W). No differences (P > 0.05) in MLSS workload were fou nd between speed skating and rowing. MLSS workload intensity as relate d to maximal workload was independent (P > 0.05) of the sports event: 76.2% +/- 5.7% in rowing, 71.8% +/- 4.1% in cycling, and 75.1% +/- 4.4 % in speed skating. Changes in MLSS do not respond with MLSS workload, the MLSS workload intensity, or with the metabolic profile of the spo rts event. The observed differences in MLSS and MLSS workload may corr espond to the sport-specific mass of working muscle.