Maximal oxygen consumption and oxygen uptake efficiency in adolescent males.

BACKGROUND/OBJECTIVE: Measures of oxygen uptake efficiency (OUE) have been used to evaluate cardiorespiratory fitness (CRF) in adolescents unable to perform maximal exercise. The oxygen uptake efficiency slope (OUES) and oxygen uptake efficiency plateau (OUEP) have been proposed as surrogates for maximal oxygen consumption (V̇O). We assessed the validity of the OUES and OUEP as predictors of V̇O in healthy male adolescents.

METHODS

Sixty-three healthy male adolescents aged 15.40 ± 0.34 years underwent an incremental treadmill test to determine V̇O, OUES and OUEP. OUE throughout the test was assessed by dividing each V̇O value by the corresponding minute ventilation (V̇) value. OUEP was determined as the 90 s average highest consecutive values for OUE. OUES was determined using data up to the ventilatory threshold (VT) by calculating the slope of the linear relation between V̇O and the logarithm of V̇.

RESULTS

Limits of agreement for V̇O predicted by OUES (±13.3 mL kgmin) and OUEP (±16.7 mL kgmin) relative to V̇O were wide and a magnitude bias was found for OUES and OUEP as predictors of V̇O (p < 0.001).

CONCLUSION

The OUES and OUEP do not accurately predict V̇O in male adolescents and should not replace V̇O when assessing CRF in this population.