The relationship between plasma lactate parameters, Wpeak and 1-h cycling performance in women.Med. Sci. Sports Exerc., Vol. 30, No. 8, pp. 1270-1275, 1998. The relationship between six descriptors of lactate increase, peak V˙O2, Wpeak, and 1-h cycling performance were compared in 24 trained, female cyclists (peak V˙O2= 48.11 ± 6.32 mL·kg−1·min−1). The six descriptors of lactate increase were: 1) lactate threshold (LT; the power output at which plasma lactate concentration begins to increase above the resting level during an incremental exercise test), 2) LT1 (the power output at which plasma lactate increases by 1 mM or more), 3) LTD (the lactate threshold calculated by the D-max method), 4) LTMOD (the lactate threshold calculated by a modified D-max method), 5) L4 (the power output at which plasma lactate reaches a concentration of 4 mmol·L−1), and 6) LTLOG (the power output at which plasma lactate concentration begins to increase when the log([La−]) is plotted against the log (power output)). Subjects first completed a peak V˙O2 test on a cycle ergometer. Finger-tip capillary blood was sampled within 30 s of the end of each 3-min stage for analysis of plasma lactate. Endurance performance was assessed 7 d later using a 1-h cycle test (OHT) in which subjects were directed to achieve the highest possible average power output. The mean power output (W) for the OHT (± SD) was 183.01 ± 18.88, and for each lactate variable was: LT (138.54 ± 46.61), LT1 (179.17 ± 27.25), LTLOG (143.97 ± 45.74), L4 (198.09 ± 33.84), LTD(178.79 ± 24.07), LTMOD (212.28 ± 31.75). Average power output during the OHT was more strongly correlated with all plasma lactate parameters (0.61< r < 0.84) and Wpeak (r = 0.81) than with peak V˙O2 (r = 0.55). The six lactate parameters were strongly correlated with each other (0.54< r < 0.91) and of the six lactate parameters, LTD correlated best with endurance performance (r = 0.84). It was concluded that plasma lactate parameters and Wpeak provide better indices of endurance performance than peak V˙O2 and that, of the six descriptors of lactate increase measured in this study, LTD is most strongly related to 1-h cycling performance in trained, female cyclists.

The purpose of this study was to examine the influence of three different high-intensity interval training (HIT) regimens on endurance performance in highly trained endurance athletes. Before, and after 2 and 4 wk of training, 38 cyclists and triathletes (mean +/- SD; age = 25 +/- 6 yr; mass = 75 +/- 7 kg; VO(2peak) = 64.5 +/- 5.2 mL x kg(-1) min(-1)) performed: 1) a progressive cycle test to measure peak oxygen consumption (VO(2peak)) and peak aerobic power output (PPO), 2) a time to exhaustion test (T(max)) at their VO(2peak) power output (P(max)), as well as 3) a 40-km time-trial (TT(40)). Subjects were matched and assigned to one of four training groups (G(2), N = 8, 8 x 60% T(max) at P(max), 1:2 work:recovery ratio; G(2), N = 9, 8 x 60% T(max) at P(max), recovery at 65% HR(max); G(3), N = 10, 12 x 30 s at 175% PPO, 4.5-min recovery; G(CON), N = 11). In addition to G(1), G(2), and G(3) performing HIT twice per week, all athletes maintained their regular low-intensity training throughout the experimental period. All HIT groups improved TT(40) performance (+4.4 to +5.8%) and PPO (+3.0 to +6.2%) significantly more than G(CON) (-0.9 to +1.1%; P < 0.05). Furthermore, G(1) (+5.4%) and G(2) (+8.1%) improved their VO(2peak) significantly more than G(CON) (+1.0%; P < 0.05). The present study has shown that when HIT incorporates P(max) as the interval intensity and 60% of T(max) as the interval duration, already highly trained cyclists can significantly improve their 40-km time trial performance. Moreover, the present data confirm prior research, in that repeated supramaximal HIT can significantly improve 40-km time trial performance.

Mental fatigue is a psychobiological state caused by prolonged periods of demanding cognitive activity shown to negatively influence physical performance. Variation exists across the literature regarding the manifestations and impact of mental fatigue; with little knowledge of the domain‐specific manifestations in elite sport. The difficulties in defining mental fatigue may explain why it is not consistently assessed by coaching or support staff. The aim of this study was therefore to investigate athlete and staff understandings of mental fatigue in elite sport. Nine focus group discussions were conducted involving a total of 32 athletes (n = 17) and staff (n = 15) from elite sporting organisations. Athletes and staff believe mental fatigue negatively impacts sporting performance. Analysis revealed perceived associations between mental fatigue and changes in behaviour including, disengagement, decreased motivation and enthusiasm, increased displays of emotion and withdrawal. Changes in concentration, decreased discipline and attention to detail also emerged as descriptors of mental fatigue. Media engagements, study and work commitments were reported to induce mental fatigue. Repetitive tasks, over‐analysis, thinking about the sport in question and environmental instability were further reported perceived causes. Experience and personality emerged as factors contributing to individual susceptibility. Mental fatigue is perceived to not only develop acutely but also build in a cumulative manner in the elite sporting environment. The present findings inform the design of future studies examining MF in elite athletes; they also hold the potential to improve how best to monitor and manage the condition in applied practice.