Physical Fitness and Performance Validation of a New Method for Estimating V̇O2max Based on V̇O2 Reserve

Sports Medicine’s (ACSM) preferred method for estimating maximal oxygen consumption (V ˙ O2max) has been shown to overestimate V ˙ O2max, possibly due to the short length of the cycle ergometry stages. This study validates a new method that uses a final 6-min stage and that estimates V ˙ O2max from the relationship between heart rate reserve (HRR) and V ˙ O2 reserve. Methods: A cycle ergometry protocol was designed to elicit 65–75 % HRR in the fifth and sixth minutes of the final stage. Maximal workload was estimated by dividing the workload of the final stage by %HRR. V ˙ O2max was then estimated using the ACSM metabolic equation for cycling. After the 6-min stage was completed, an incremental test to maximal effort was used to measure actual V ˙ O2max. Forty-nine subjects completed a pilot study using one protocol to reach the 6-min stage, and 50 additional subjects completed a modified protocol. Results: The pilot study obtained a valid estimate of V ˙ O2max (r 0.91, SEE 3.4 mL·min1·kg1) with no over- or underestimation (mean estimated V ˙ O2max 35.3 mL·min1·kg1, mean measured V ˙ O2max 36.1 mL·min1·kg1), but the average %HRR achieved in the 6-min stage was 78%, with several subjects attaining heart rates considered too high for submaximal fitness testing. The second study also obtained a valid estimate of V ˙ O2max (r 0.89, SEE 4.0 mL·min1·kg1) with no over- or underestimation (mean estimated V ˙ O2max 36.7 mL·min1·kg1, mean measured V ˙ O2max 36.9 mL·min1·kg1), and the average %HRR achieved in the 6-min stage was 64%. Conclusions: A new method for estimating V ˙ O2max from submaximal cycling based on V ˙ O2 reserve has been found to be valid and more accurate than previous methods. Key Words: MAXIMAL OXYGEN CONSUMPTION, CYCLE ERGOMETRY, EXERCISE TESTING, FITNES