Aerobic fitness level has implications in weight loss maintenance
Click Here to Manage Email Alerts
Improvement in aerobic capacity led to a greater percentage of weight loss in select populations, according to data scheduled to be presented at the ACP Internal Medicine Meeting.
ACP cancelled its annual meeting because of COVID-19, but the organization posted a video of the presentation, which was recorded and submitted by the researchers.
“VO2 max is a measure of aerobic capacity or fitness measured in milliliters of oxygen per kilogram of body weight ... with a heart rate monitor and oxygen mask while on a stationary bike or a treadmill,” Erin O’Keefe, a medical student at the University of Miami Miller School of Medicine, said during the presentation. “Research has not clearly elucidated the ways in which physical activity and modification of the VO2 max impacts long-term weight loss.”
Researchers hypothesized that persons who participated in the Michigan Weight Management Program would have significant improvements in weight loss and maximal exercise capacity. “We also sought to evaluate whether a higher baseline VO2 max or a change in fitness resulted in greater weight loss maintenance,” O’Keefe said.
To test their hypothesis, researchers conducted a prospective, observational study of 115 individuals aged 20 to 70 years who had a BMI greater than 32 kg/m2 and a “weight-related health condition” such as type 2 diabetes. Participants’ weight and VO2 max levels were checked at baseline and at 2 years. after they participated in the University of Michigan’s Weight Management Program. According to O’Keefe, the intensive, multidisciplinary, multicomponent lifestyle program was comprised of three stages: initial weight loss, where participants incorporated a very-low energy diet in the form of total meal replacement shakes; gradual transition, where participants consume a low-calorie food-based diet; and weight maintenance, where participants make frequent, regular visits to a physician and dietitian to support continued behavioral changes. All participants were also encouraged to engage in mild to moderate physical activity during the first two phases and then engage in moderate to more vigorous physical activity during the final phase.
O’Keefe and colleagues found that after completing the program, 39% of the 59 men improved their VO2 max level by one or more categories. Almost half of the men stayed in the same VO2 max category. Among the 56 women in the study, 34% improved their VO2 max level while 55% stayed at the same level. The increase in VO2 max categories relative to percent weight loss was statistically significantly higher in women aged 40 to 49 years and in men aged 50 to 59 years. Higher VO2 max at baseline was statistically significant in men and women aged 50 to 59 years.
“This suggests that participants ... lost a lot of weight and improved their level of fitness,” O’Keefe said. “However, we cannot conclude causality in this study. But we do know that diet and physical activity are strongly integrated behaviors and it is encouraging that patients are simultaneously losing weight and getting fitter.”
She suggested that further studies control for other variables, such as medications, that could impact weight loss. “Survey instruments on physical activity could be designed to validate self-reported data,” O'Keefe added.