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The present study examined the use of the maximal lactate steady state (MLSS) as an exercise training stimulus in moderately trained runners. Fourteen healthy individuals (12 male, 2 female; age 25 ± 6 years, height 1.76 ± 0.05 m, body mass 76 ± 8 kg mean ± SD) took part in the study. Following determination of the lactate threshold (LT), VO2max, running velocity at MLSS (vMLSS) and a control period of 4 weeks, participants were pair matched and split into two cohorts performing either continuous (CONT: 2 sessions/ week at vMLSS) or intermittent treadmill running (INT: 2 sessions/week, 3-mm repetitions 0.5 km·h-1 above and below vMLSS). vMLSS increased in CONT by 8% from 12.3 ± 1.5 to 13.4 ± 1.6 km · h-1 (p <0.05) and in INT by 5% from 12.2± 1.9 km · h-1 to 12.9 ± 1.9 km · h-1 (p<0.05). Running speed at the LI increased by 7% in the CONT group (p <0.05) and by 9% in the INT group (p<0.05). VO2max increased by 10% in the CONT group (p <0.05) and by 6% in INT (p <0.05). Two sessions per week at vMLSS are capable of eliciting improvements in the physiological responses at LT, MLSS, and VO2max in moderately trained runners. [ABSTRACT FROM AUTHOR]

The curvature of the power-time (P-t) relationship (W') has been suggested to be constant when exercising above critical power (CP) and to represent the anaerobic work capacity (AWC). The aim of this study was to compare W' to (1) the total amount of work performed above CP (W (90s)') and (2) the AWC, both determined from a 90s all-out fixed cadence test. Fourteen participants (age 30.5 +/- 6.5 years; body mass 67.8 +/- 10.3 kg), following an incremental VO(2max) ramp protocol, performed three constant load exhaustion tests set at 103 +/- 3, 97 +/- 3 and 90 +/- 2% P-VO(2max) to calculate W' from the P-t relationship. Two 90s all-out efforts were also undertaken to determine W (90s)' (power output-time integral above CP) and AWC (power output-time integral above the power output expected from the measured VO(2)). W' (13.6 +/- 1.3 kJ) and W (90s)' (13.9 +/- 1.1 kJ; P = 0.96) were not significantly different but were lower than AWC (15.9 +/- 1.2 kJ) by 24% (P = 0.03) and 17%, respectively (P = 0.04). All these variables were correlated (P < 0.001) but great extents of disagreement were reported (0.2 +/- 6.4 kJ between W' and W (90s)', 2.3 +/- 7.2 kJ between W' and AWC, and 2.1 +/- 4.3 kJ between W (90s)' and AWC). The underestimation of AWC from both W' and W (90s)' can be explained by the aerobic inertia not taking into consideration when determining the two latter variables. The low extents of agreement between W', W (90s)' and AWC mean the terms should not be used interchangeably. [ABSTRACT FROM AUTHOR]