Defining Intensity Domains from the End Power of a 3-min All-out Cycling Test

Abstract

The purpose of this study was to develop a modified version of a 3-min all-out cycling test (3MT) using equipment readily available to cyclists and to identify exercise intensity domains using the average power output over the last 30 s of the 3MT (end-test power (EP)). Sixteen competitive cyclists (V(O2peak) = 60.3 +/- 8.3 mL.kg.min) completed three laboratory visits using their own bicycles and a power-measuring rear wheel. In visit 1, subjects performed an incremental load test to volitional termination on an electronically braked trainer (100 + 25 W every 4 min). Power output at lactate threshold was determined by absolute 4 mmol.L (OBLA-PO) and 1 mmol.L over exercise baseline (LT-PO). Power output at ventilatory threshold (VT-PO) was computed on the basis of the V-slope method. Power output at V(O2peak) (V(O2peak)-PO) was the mean power observed during the stage at which peak O2 consumption was recorded. In visits 2 and 3, subjects performed the 3MT using a progressive resistance trainer with Visit 2 as a familiarization trial. During Visit 3, EP was recorded. EP (273 +/- 52 W) was significantly greater than VT-PO, OBLA-PO, and LT-PO (232 +/- 64, 235 +/- 54, and 208 +/- 45 W, respectively) but significantly less than V(O2peak)-PO (288 +/- 56 W). EP was correlated with V(O2peak)-PO (r = 0.97), VT-PO (r = 0.87), OBLA-PO (r = 0.85), and LT-PO (r = 0.79) with regression estimates through the origin made using 105%, 86%, 86%, and 76% of EP, respectively. Demarcations for moderate- to heavy-intensity (LT-PO at 76% EP) and heavy- to severe-intensity (100% EP) domains may be estimated. The 3MT can be used to define exercise intensity in competitive cyclists using readily available equipment.