External validation of VO2max prediction models based on recreational and elite endurance athletes

Abstract

In recent years, numerous prognostic models have been developed to predict VO2max. Nevertheless, their accuracy in endurance athletes (EA) stays mostly unvalidated. This study aimed to compare predicted VO2max (pVO2max) with directly measured VO2max by assessing the transferability of the currently available prediction models based on their R2, calibration-in-the-large, and calibration slope. 5,260 healthy adult EA underwent a maximal exertion cardiopulmonary exercise test (CPET) (84.76% male; age 34.6±9.5 yrs.; VO2max 52.97±7.39 mL·min-1·kg-1, BMI 23.59±2.73 kg·m-2). 13 models have been selected to establish pVO2max. Participants were classified into four endurance subgroups (high-, recreational-, low- trained, and “transition”) and four age subgroups (18–30, 31–45, 46–60, and ≥61 yrs.). Validation was performed according to TRIPOD guidelines. pVO2max was low-to-moderately associated with direct CPET measurements (p>0.05). Models with the highest accuracy were for males on a cycle ergometer (CE) (Kokkinos R2 = 0.64), females on CE (Kokkinos R2 = 0.65), males on a treadmill (TE) (Wasserman R2 = 0.26), females on TE (Wasserman R2 = 0.30). However, selected models underestimated pVO2max for younger and higher trained EA and overestimated for older and lower trained EA. All equations demonstrated merely moderate accuracy and should only be used as a supplemental method for physicians to estimate CRF in EA. It is necessary to derive new models on EA populations to include routinely in clinical practice and sports diagnostic.

VO2maxprediction based on submaximal cardiorespiratory relationships and body composition in male runners and cyclists: a population study

“…As an additional advantage, we propose an equation based only on somatic variables, which showed a low R 2 -0.35 for runners and 0.43 for cyclists. Although, it still presents that our models are more accurate than those widely described in the literature so far (Paap and Takken, 2014;Wiecha et al, 2023).…”

“…Therefore, new opportunities to develop more precise yet simple and accessible methods and models to assess VO 2max occur. This appears to be especially important considering the low prediction accuracy of most of the VO 2max formulas that were validated in our previous study (Wiecha et al, 2023).…”

Applied high-intensity interval cardio yoga improves cardiometabolic fitness, energetic contributions, and metabolic flexibility in healthy adults

“…Then, the running speed was increased by 0.72 km·h −1 every 30 s. The investigator verbally encouraged participants to maintain effort for as long as possible to evaluate their maximum aerobic performance seen as reaching a “plateau”. The test was stopped when O 2 plateau and respiratory exchange ratio (RER) >1.0 were reached, or until volitional exhaustion by the participant ( Jurov et al, 2023 ; Wiecha et al, 2023 ). The plateau was determined using the method (<2 mL·kg −1 ·min −1 ) that has been explained in previous studies ( Krustrup et al, 2005 ; Niemeyer et al, 2021 ).…”

Validity of the Maximal Heart Rate Prediction Models among Runners and Cyclists

“…The intensity was adjusted by the physiologist in conjunction with the trainee to reach their maximum exertion. The termination points considered as a maximal effort were: (1) volitional exhaustion and inability to continue the protocol with declared exertion ≥18 in Borg's RPE, (2) an HR or oxygen uptake (VO2) plateau (a stable level of HR or levelling-off in VO2, defined as an increase <100 mL•min −1 with growing exercise intensity before CPET termination) [20][21][22].…”