PubMed Health⌕ Search

Biomedical subjects

Sylvie St-Pierre

Publications and source records attributed to Sylvie St-Pierre.

2 recordsLinked to original sources
PubMed2003

Relation between appetite ratings before and after a standard meal and estimates of daily energy intake in obese and reduced obese individuals.

The aim of the present study was to relate appetite ratings before and after a standard breakfast to estimates of daily energy intake, before and after weight loss obese men and women. Nineteen obese subjects (9 men and 10 women) took part in a 15-week drug-based weight-loss program coupled to energy intake restriction. Body weight and body composition were significantly decreased in men and women. Both before and after the weight loss program, desire to eat, hunger, fullness and prospective food consumption (PFC) were measured after an overnight fast and at 10-min intervals in the hour following the ingestion of a standardized breakfast. Energy intakes were also measured and reported before and after weight loss. Fasting desire to eat and postprandial area under the curve (AUC) for hunger were significantly increased (p<0.05) after the intervention. No association was observed between measured or reported energy intakes and appetite ratings before weight loss in either men or women. Reported energy intake was not associated with appetite sensations after weight loss either. In contrast, measured energy intake was significantly associated with postprandial AUC for fullness (r=-0.90, p<0.01) and PFC (r=0.80, p<0.01) in men at the end of the program. In stepwise multiple regression analysis, only postprandial AUC for PFC contributed independently to the variance of measured energy intake after weight loss (r(2)=0.60, p=0.01). This study did not show consistent associations between averaged appetite ratings after a meal and daily energy intake, either before or after weight loss.

Adult↗
PubMed2003

Greater than predicted decrease in energy expenditure during exercise after body weight loss in obese men.

This study was performed retrospectively to investigate whether exercise energy expenditure (EE) measured during a standardized treadmill protocol (4.5 km/h at 0% grade) falls below predicted values after body weight loss in obese men. A reference equation was established to predict net exercise EE in a control sample of 83 obese individuals (27 kg/m(2)< or = body mass index <45 kg/m(2)), using age, fat mass and fat-free mass as independent variables. This equation was then used to predict net exercise EE in another group of 11 obese men before and after a 15-week drug-based weight loss programme that was coupled with energy restriction [-2929 kJ/day (-700 kcal/day)]. Body weight and body composition were determined by hydrodensitometry. Net exercise EE, insulin, leptin, 3,3',5-tri-iodothyronine and free thyroxine were measured after an overnight fast at baseline and 2-4 weeks after the end of the programme, when subjects were weight stable. Body weight was significantly reduced (-11%; P <0.01) at the end of the weight loss programme. At baseline, measured net exercise EE was similar to that predicted from the regression equation [19.6 and 19.8 kJ/min (4.69 and 4.74 kcal/min) respectively; not significant]. However, after the end of the intervention, measured net exercise EE was significantly below the predicted value [15.5 and 17.3 kJ/min (3.71 and 4.14 kcal/min) respectively; P <0.01]. The difference between the predicted and the measured fall in net exercise EE was significantly associated with changes in leptin concentration ( r =0.79, P <0.01), even after correction for changes in fat mass and insulin. These observations suggest that net exercise EE falls below predicted values after body weight loss. In addition, this greater than predicted decrease in net exercise EE was associated with changes in leptin.

Adult↗