Abstract
Background: Higher cardiorespiratory fitness is associated with a reduced risk of all-cause and cardiovascular disease mortality in healthy individuals. This relationship is also true for those with type 2 diabetes (T2D). Cardiopulmonary exercise tests to determine cardiorespiratory fitness (measured as peak oxygen uptake [Vradical dotO2peak]) may not always be achievable in those with T2D. Intrinsic factors such as lack of motivation or peripheral fatigue, along with limitations in personnel required to supervise the exercise test in high-risk individuals, limit the utility of the test. The oxygen uptake efficiency slope (OUES) represents the efficiency of the body to extract oxygen from ventilation and measuring this during submaximal efforts may be a valid measure of cardiorespiratory fitness. The aim of this study was to compare the association between submaximal OUES and Vradical dotO2peak in participants with T2D.
Methods: Eight adults (59 ± 7 years) with overweight/obesity (BMI = 37.5 ± 6.1 kg/m2) and T2D (glycated haemoglobin [HbA1c] 63 ± 11 mmol/mol) completed a maximal graded cardiopulmonary exercise test on a treadmill. Vradical dotO2peak was determined as the mean of the three continuously high ten second measurements attained during the test. The OUES was calculated as the slope of oxygen uptake against the logarithm of total ventilation for the entire test [Vradical dotO2 (L/min) = m(logVradical dotE) + B, where m = OUES]. Correlation between Vradical dotO2peak and the OUES was determined via Pearson's correlation coefficient. Statistical significance was set at p < 0.05. Values are reported as means ± SD.
Results: Participants’ Vradical dotO2peak was 2.4 ± 0.5 L/min and OUES 2.1 ± 0.9. The correlation between Vradical dotO2peak and the OUES was strong and significant (r = 0.8; p = 0.019).
Conclusion: The OUES displayed a strong and significant association with Vradical dotO2peak. This suggests that the OUES may offer a valid submaximal measure of cardiorespiratory fitness in overweight and obese participants with T2D.
Trial registration: Australian New Zealand Clinical Trials Registry ACTRN12615000475549.
Methods: Eight adults (59 ± 7 years) with overweight/obesity (BMI = 37.5 ± 6.1 kg/m2) and T2D (glycated haemoglobin [HbA1c] 63 ± 11 mmol/mol) completed a maximal graded cardiopulmonary exercise test on a treadmill. Vradical dotO2peak was determined as the mean of the three continuously high ten second measurements attained during the test. The OUES was calculated as the slope of oxygen uptake against the logarithm of total ventilation for the entire test [Vradical dotO2 (L/min) = m(logVradical dotE) + B, where m = OUES]. Correlation between Vradical dotO2peak and the OUES was determined via Pearson's correlation coefficient. Statistical significance was set at p < 0.05. Values are reported as means ± SD.
Results: Participants’ Vradical dotO2peak was 2.4 ± 0.5 L/min and OUES 2.1 ± 0.9. The correlation between Vradical dotO2peak and the OUES was strong and significant (r = 0.8; p = 0.019).
Conclusion: The OUES displayed a strong and significant association with Vradical dotO2peak. This suggests that the OUES may offer a valid submaximal measure of cardiorespiratory fitness in overweight and obese participants with T2D.
Trial registration: Australian New Zealand Clinical Trials Registry ACTRN12615000475549.
| Original language | English |
|---|---|
| Article number | 225 |
| Pages (from-to) | 80-81 |
| Number of pages | 2 |
| Journal | Obesity Research and Clinical Practice |
| Volume | 13 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - Jan 2019 |
| Externally published | Yes |
Keywords
- Diabetes
- cardiorespiratory fitness
- oxygen uptake