Does when you eat and exercise matter? Differences in eating and physical activity patterns in overweight and obese adults

Despite current recommendations and guidelines on the treatment of overweight and obesity, little is known about what patterns of energy intake or expenditure are ideal for weight loss. The present study examined patterns in energy intake and expenditure and explored whether those differences were associated with weight loss. Self-monitoring data on energy intake and expenditure, along with minutes spent in exercise, were obtained from 90 overweight or obese adults (mean BMI = 38.0) enrolled in two behavioral weight loss programs. Energy intake and minutes of daily exercise were self-reported and energy expenditure was obtained from the Caltrac accelerometers that were provided to participants. On weekends (Friday through Sunday), participants consumed more calories from breakfast (271 vs. 241 kcals/day; p < .01), dinner (605 vs. 547 kcals/day; p < .001), and alcohol (59 vs. 27 kcals/day; p < .01), as well as total daily calories (1669 vs. 1520 kcals/day; p < .001) and expended fewer total calories (2515 vs. 2614 kcals/day; p < .01) than on weekdays. Higher caloric intake on weekdays was associated with less overall weight loss (r = -.29, p < .01) and was marginally associated on weekends (r = -.19, p = .051). This investigation found evidence that while eating patterns clearly contribute to daily energy intake on weekdays and weekends, they may not necessarily contribute to weight change. At the end of the day, what may be most important is regular self-monitoring and total caloric intake on both the weekdays and weekends.