Physical activity patterns during weight maintenance following a low-energy density dietary intervention

OBJECTIVE

The objective was to determine the role of physical activity (PA) and energy intake on weight maintenance among former University of Alabama at Birmingham EatRight Weight Management Program participants.

RESEARCH METHODS AND PROCEDURES

Eighty-nine former participants completed follow-up visits > or =1 year after completing EatRight. BMI was calculated using measured height and weight. Diet intake was estimated from 4-day food records. PA was assessed using a module from the Behavioral Risk Factor Surveillance System Survey. Cut-off points were chosen based on the distribution of minutes of activity. For moderate and total activity, cut-off points were 0, 1 to 30, 31 to 60, and >60 minutes. For vigorous activity, the categories were 0, 1 to 20, 21 to 30, and >30 minutes. General linear models determined the association of PA with change in weight at follow-up controlling for gender and total energy intake (kcal/d).

RESULTS

At follow-up, 80% (n = 71) of participants maintained (regained <5% of program end weight) their body weight and 20% had gained weight. Mean weight change was 1.0 +/- 6.5 kg. Maintainers consumed 384 fewer kcal/d on average. Maintainers had a lower energy density dietary pattern (1.58 vs. 2.01 kcal/g, p < 0.01). There was no significant difference in PA min/d reported by maintainers and gainers.

DISCUSSION

Our results suggest that, despite being minimally active, weight-reduced individuals can successfully maintain their newly achieved body weight with appropriate caloric intake. Adopting a lower calorie, low energy density dietary pattern may reduce the amount of PA that is truly necessary for weight maintenance.

Diet variety based on macronutrient intake and its relationship with body mass index

CONTEXT

Increased dietary variety has been associated with increased body weight; however, diet variety is not measured using a standardized methodology.

OBJECTIVE

We developed a new dietary variety score (DVS) based on food macronutrient content, and determined the relationship between DVS and measures of adiposity.

DESIGN

Cross-sectional, observation study.

SETTING

University of Alabama at Birmingham (UAB), EatRight Weight Management Program.

PATIENTS

Study subjects (n = 74) were former participants of UAB's EatRight Weight Management Program who completed the program at least 1 year ago.

MAIN OUTCOME MEASURES

Unique items from 4-day food records were converted to macronutrient categories using the diabetic exchange. Foods were categorized as a source of carbohydrate if containing > or = 5 g carbohydrate and > or = 20 calories; fat if containing > or = 5 g fat; protein if containing > or = 7 g protein. Height and weight were measured; BMI (kg/m2) was calculated. Dual energy X-ray absorptiometry measured body fat. Generalized linear modeling in SAS (Ver.9) determined relationships between adiposity and DVS.

RESULTS

On average, participants weighed 92.7 -/+ 30.9 kg (BMI = 32.5 kg/m2). Men and women's body fat were 37.4 -/+ 6.4% and 47.3 -/+ 6.4%, respectively. Separate linear regression models containing terms for sex and DVS showed significant relationships between macronutrient DVS and BMI. In a multivariate model controlling for each of the macronutrient DVS, BMI was not related to fat DVS, but was found to be positively related to protein DVS (beta = 0.87, P = .04). Sex modified the relationship between carbohydrate DVS and BMI, with an inverse relationship between BMI and carbohydrate DVS among women, and a positive relationship among men. Percent body and trunk fat were not related to DVS for either gender.

CONCLUSIONS

The new DVS, based on macronutrient content of foods, had significant associations with BMI. These dietary variety scores may provide another way to evaluate the impact of consuming a variety of food types on energy intake and BMI.