Using a Verification Test for Determination of V[Combining Dot Above]O2max in Sedentary Adults With Obesity

Abstract

A constant-load exercise bout to exhaustion after a graded exercise test to verify maximal oxygen uptake (V[Combining Dot Above]O2max) during cycle ergometry has not been evaluated in sedentary adults with obesity. Nineteen sedentary men (n = 10) and women (n = 9) with obesity (age = 35.8 ± 8.6 years; body mass index [BMI] = 35.9 ± 5.1 kg·m; body fat percentage = 44.9 ± 7.2) performed a ramp-style maximal exercise test (ramp), followed by 5-10 minutes of active recovery, and then performed a constant-load exercise bout to exhaustion (verification test) on a cycle ergometer for determination of V[Combining Dot Above]O2max and maximal heart rate (HRmax). V[Combining Dot Above]O2max did not differ between tests (ramp: 2.29 ± 0.71 L·min, verification: 2.34 ± 0.67 L·min; p = 0.38). Maximal heart rate was higher on the verification test (177 ± 13 b·min vs. 174 ± 16 b·min; p = 0.03). Thirteen subjects achieved a V[Combining Dot Above]O2max during the verification test that was ≥2% (range: 2.0-21.0%; 0.04-0.47 L·min) higher than during the ramp test, and 8 subjects achieved a HRmax during the verification test that was 4-14 b·min higher than during the ramp test. Duration of verification or ramp tests did not affect V[Combining Dot Above]O2max results, but the difference in HRmax between the tests was inversely correlated with ramp test duration (r = -0.57, p = 0.01). For both V[Combining Dot Above]O2max and HRmax, differences between ramp and verification tests were not correlated with BMI or body fat percentage. A verification test may be useful for identifying the highest V[Combining Dot Above]O2max and HRmax during cycle ergometry in sedentary adults with obesity.

Verification of Maximal Oxygen Uptake in Obese and Nonobese Children

“…Using data from Poole et al (32), we estimated that a sample size of 16 participants would detect differences between incremental and verification tests at 80% power (α = 0.05; effect size = 0.759; two tailed hypothesis; based on a t test analysis) (15). The sample size of this study is comparable to other studies that have examined differences in V̇O 2 between incremental and verification tests (7, 22, 38) and to studies had have examined the validity of secondary criteria for establishing V̇O 2max (7, 32). All data were checked to ensure normal distribution.…”

“…In obese adults, a study by Sawyer et al (38) did not find significantly higher verification V̇O 2 when compared with incremental V̇O 2 , even though they did show substantial individual variability in the results with 13 out of 19 subjects achieving a V̇O 2 during verification testing that was 2 to 21% higher than the incremental test. The authors did not observe any relationship between BMI and performance on the verification test, which is consistent with the lack of differences between obese and nonobese groups in the present study.…”

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

“…However, it should be noted that what is reported is group mean differences, which do not identify individuals who may not have attained a true . Using a larger sample size than in previous studies (n = 100), we found differences between GXT and VerT in the range of previous reports (2%‐3% ). However, upon identification of individuals with lower GXT the difference tripled.…”

“…A few studies in the literature evaluate the attainment of in obese individuals . The authors in two of these studies suggest that using verification test in obese sedentary adults may be useful and superior to secondary criteria . However, values during GXT and VerT were not statistically different.…”

“…In contrast, other authors propose the use of a verification test for stratifying heart failure patients for surgery . It is unclear if a verification test improves assessment of obese unfit MetS individuals.…”