THE EFFECT FOUR AND EIGHT MINUTE INCREMENTS ON INITIAL BLOOD LACTATE PROFILING, AND SUBSEQUENT PRESCRIPTION OF A TRAINING INTENSITY IN HIGHLY TRAINED ROWERS

Abstract

The purpose of this present study is to investigate how variations in exercise stage duration (4-min vs. 8-min) influence blood lactate, heart rate (HR) and rating of perceived exertion (RPE) profiles in highly trained rowers (n = 7) during laboratory-based, ergometry testing. A specific emphasis was placed upon the determination of fixed blood lactate concentration (FBLC) of 2 and 4 mmol·l-1. Subsequently, participants were required to complete two, 15-min tests at the power outputs equivalent to the 2 mmol·l-1 derived from both tests. During these 15-min tests HR and RPE was monitored and whole blood lactate concentration was measured immediately after each test. Statistical analysis consisted of two-way repeated measures analysis of variance, and paired t-tests. Results revealed significantly higher (P < 0.05) blood lactate concentrations, HR readings and RPE reports between the 8-min protocol when compared to the 4-min. Furthermore, FBLC of 2 and 4 mmol·l-1 were greater when derived from the 4-min protocol in comparison to the 8-min, only 4 mmol·l-1 was significant (P < 0.05). Results from the two, monitored sessions demonstrated significantly (P < 0.05) higher results during the 4-min derived power, in comparison to the 8-min derived power. Additionally, mean concentration of blood lactate immediately following the two monitored tests were different (P < 0.05) with a higher value being reported after the monitored session prescribed using the 4-min incremental test. Findings were attributed to increased stage duration allowing sufficient time for equilibrium in blood lactate concentration and stabilisation of HR. Results of the current study may differ from previous research in cycling, due to a greater muscle mass recruitment required for rowing exercise. In conclusion, if incremental testing is required in order for the training management of highly-trained athletes, endurance measurements need to represent longer durations of work in order to consider all the kinetics of the physiological variables measured, in addition to requirements of the mode of exercise.