Importance of a verification test to accurately assess V̇O₂max in unfit individuals with obesity

Abstract

Background To determine the trustworthiness of graded exercise test to exhaustion (GXT) to assess maximal oxygen uptake (normalV˙O2max) in metabolic syndrome individuals with obesity and poor cardiorespiratory fitness. Methods normalV˙O2max was assessed in 100 metabolic syndrome adults (57 ± 8 years; 34% women), with obesity (BMI 32 ± 5 kg·m−2) using GXT followed by supramaximal constant‐load verification test (VerT) at 110% of maximal GXT work rate. trueV˙normalO2 data from GXT and VerT were compared using paired t test and plotted for Bland‐Altman analysis. GXT sensitivity and specificity to detect normalV˙O2max were also calculated. Results Seventy individuals did not achieve trueV˙normalO2 plateau during GXT. GXT underestimated normalV˙O2max in 40 subjects. In these subjects, the magnitude of normalV˙O2max underestimation with GXT was 9% (167 mLO2·min−1; P < .001). In the whole sample (n = 100), bias error differences between GXT and VerT was 63 mLO2·min−1 (3% underestimation). This error was constant regardless of differences in fitness levels among individuals (R = −0.07; homoscedasticity). GXT results were unreliable in 62% of the sample with 16% of false‐positive and 46% of false‐negative results. Sensitivity and specificity of GTX to assess normalV˙O2max were low (ie, 23% and 60%, respectively). Conclusion Our data indicate that the magnitude (3%‐9%) and prevalence (40% of subjects) of normalV˙O2max underestimation with the use of a GXT alone is high in a large sample of unfit metabolic syndrome individuals with obesity. Our data advocate for the need of using VerT after GXT to avoid significant cardiorespiratory fitness underestimation in metabolic syndrome individuals with obesity and low fitness level.

Effects of antihypertensive medication and high‐intensity interval training in hypertensive metabolic syndrome individuals

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Concurrent endurance and resistance training enhances muscular adaptations in individuals with metabolic syndrome

“…At least 72 hours separated the last training session from testing protocols after training. Then, a graded exercise test (GXT) was conducted in a calibrated cycle ergometer as previously described 33 to measure maximal cycling power (ie, cycling W MAX ).…”

Effects of statins and exercise on postprandial lipoproteins in metabolic syndrome vs metabolically healthy individuals

“…Subjects underwent a medical physical examination and completed a maximal cardiopulmonary graded exercise test to exhaustion on an electronically braked cycle ergometer (Ergoselect 200, Ergoline, Germany) with electrocardiography monitoring (Quark T12, Cosmed, Italy) to screen for myocardial diseases and determine their maximal oxygen consumption (VO 2MAX ). After a cool down and 15 minutes of passive rest including rehydration, a short (2–3 min) confirmatory test was performed at 110% of the maximum load reached during the previous ramp test 13 . The VO 2MAX obtained was used to set exercise intensity during the exercise bout.…”