Quantifying Physiological Benefit from Improvements in Exercise Tolerance

To determine whether a novel algorithm accounts for inter-individual differences in the relationship between physiological and mechanical responses to RI exercise, thus accurately estimating a CWR corresponding to a 6 min t sub(lim) (WR sub(6)). 60 men (mean + or - SD: 23 + or - 4 yr, 179 + or - 7 cm, 78 + or - 11 kg) performed 3 protocols to intolerance using electromagnetically-braked cycle ergometry: 1) RI test (15 to 30 W/min) for WR sub(peak) and VO sub(2peak); 2) CWR test at WR sub(6) estimated using the algorithm: WR sub(peak) - (2 * RI rate); 3) Series of CWR tests to determine critical power (CP), the curvature constant (W'), and interpolate 'true' WR sub(6). Fitness varied widely among participants: lactate threshold 25 + or - 5 (range: 16 - 37) mL/min/kg; CP 3.0 + or - 0.5 (1.5 - 4.8) W/kg; W' 239 + or - 49 (136 - 360) J/kg; VO sub(2max) 51 + or - 7 (36 - 75) mL/min/kg.