OBJECTIVE: The aim of the present study was to determine the impact of weight loss on appetite as measured by visual analog scale (VAS). METHODS: Seventeen subjects (10 men and seven women) took part in a 15 week weight loss program which consisted of drug therapy (fen¯uramine 60 mgaday) or placebo coupled to an energy restriction (À2930 kJaday; phase 1) followed by an 18 week low-fat diet ± exercise follow-up (phase 2). Subjects were given a standardized breakfast before and after phase 1 as well as after phase 2. Individuals were asked to ®ll out VAS before and at 0, 10, 20, 30, 40, 50 and 60 min after this test meal. Blood samples were drawn before the meal and at 0, 30 and 60 min postprandially and analyzed for glucose and insulin. Fasting plasma cortisol and leptin were also determined. RESULTS: An increase in the fasting desire to eat, hunger and prospective food consumption (PFC) was observed after phase 1 and to an even greater extent after phase 2 in both men and women. In the fasting state, positive correlations were observed between changes in the desire to eat (r 0.76; P`0.05) as well as changes of PFC (r 0.82; P`0.05) and changes in cortisol at the end of phase 1 for women. In response to phase 1, statistically signi®cant correlations were found between changes of hunger (r 0.64; P`0.05) and desire to eat (r 0.67; P`0.05) as measured by AUC in response to the meal and changes of fasting plasma cortisol in men. The most consistent predictor of changes of baseline desire to eat (r 0.68 P`0.05), fullness (r À0.78, P`0.05) and PFC (r 0.91, P`0.01) during phase 2 was the change in fasting cortisol in men. Changes of fullness were also associated with changes of fasting leptin in men (r 0.68; P`0.05) during phase 2. CONCLUSION: These results suggest that weight loss is accompanied by an increase of baseline appetite in both men and women and that the most consistent predictor of these changes in appetite seems to be changes in fasting plasma cortisol.

The main objective of the present study was to evaluate the short-term effects of exercise of different intensities on energy intake. Eleven young men were submitted to three randomly assigned sessions (one control and two exercise sessions) in which they ate, ad libitum, foods from a buffet-type meal.The energy cost of exercise was the same in the two exercise sessions. Results showed that there was no significant change in post-exercise subjective levels of hunger and fullness as well as total energy and macronutrient intakes in comparison with the control session. However, when energy intake relative to expenditure was considered by subtracting the surplus of energy expended during exercise from total energy intake, high-intensity exercise exerted a greater reducing effect on this variable compared with the control and low-intensity exercise sessions. These d t s suggest that for a given level of energy expenditure, high-intensity exercise favours negative energy balance to a greater extent than low-intensity exercise. Appetite: Energy expenditure: Physical activity: HungerThe ability of exercise to induce a negative energy balance depends on its impact on energy expenditure and is also related to variations in post-exercise energy intake. Indeed, a highfat diet has been shown to induce a considerable increase in post-exercise energy intake (Tremblay et al. 1994a;King & Blundell, 1995). This effect of diet composition on energy intake also emphasizes the importance of taking into account the potential effect of exercise on food preferences and relative macronutrient intake. In several studies, exercise has been shown to induce a substantial increase in carbohydrate intake (Thompson et al. 1988; Verger et al. 1992) whereas an increase in post-exercise protein intake was found in another study (Verger et al. 1994). However, other investigators did not find a significant effect of exercise on macronutrient intake (King et al. 1994).Experimental evidence suggests that post-exercise energy intake is also influenced by the composition of the substrate mix oxidized during exercise. Indeed, Alm6ras et al.(1 995) observed that high-fat oxidizers during exercise displayed a lower post-exercise energy intake adjusted for the energy cost of exercise compared with individuals expending less energy as fat during exercise. This observation is concordant with our previous finding that exercise may attenuate the impact of a high-fat diet on energy intake depending on its enhancing effect on fat oxidation (Tremblay et al. 1989).Other studies have also investigated the effects of exercise on energy intake and feeding behaviour. In human subjects, most of the reported studies have shown that exercise does not significantly modify appetite or the subjective feelings of hunger and fullness (Reger et al. 1986;Reger & Allison, 1987;Thompson et al. 1988;Kissileff et al. 1990). On the other hand, Kissileff et al. (1990) found that energy intake was lower only after strenuous exercise in lean female subjects. King et al. (1994) have...

The results suggest that HIE increases energy intake in women.

OBJECTIVES: To investigate the relationships of fat cell weight (FCW) as well as of estimated total adipose cell number to fasting plasma leptin concentration. DESIGN: Cross-sectional correlational study. SUBJECTS: A sample of 63 men (mean age AE s.d.: 36 AE 4 y) and 42 premenopausal women (35 AE 5 y). MEASUREMENTS: Adipose tissue (AT) biopsies were obtained in order to determine FCW as well as estimated adipose cell number. Fasting plasma leptin and insulin concentrations as well as various fatness and body fat distribution variables (underwater weighing and computed tomography) were also measured. RESULTS: In both genders, mean FCW as well as the estimated adipose cell number were signi®cantly correlated with body fatness and AT distribution variables (0.41 r 0.84). Larger abdominal (P`0.005) and femoral (P`0.0001) FCW were found in women than in men. This gender difference in adipose cell size was associated with increased leptin concentrations in women compared with men. In both genders, increased abdominal FCW was associated with higher plasma leptin concentrations (men: r 0.38, P`0.005 and women: r 0.55, P`0.0001). However, the association between femoral FCW and leptinemia was only signi®cant in women (r 0.45, P`0.005). Contrary to women, plasma leptin concentrations were associated with estimated adipose cell number in men (r 0.59, P`0.0001). Multiple regression analyses revealed that gender (43.3%), mean FCW (16.2%) and the estimated adipose cell number (10.1%) were signi®cant predictors of fasting leptinemia. CONCLUSIONS: Results of the present study indicate that in men and women, adipose cell hypertrophy is associated with increased plasma leptin concentrations. This ®nding provides further support to the observation that adipose tissue leptin secretion may be regulated, at least to a certain extent, by adipocyte size. Thus, the present study suggests that the higher plasma leptin concentrations found in women than in men could be partly explained by the well documented gender difference in adipose cell size and number.

Organochlorine compounds are released from body fat into the bloodstream during weight loss. Because these compounds may impair thyroid status, which is implicated in the control of resting metabolic rate (RMR), the aim of this study was to determine if the augmentation in plasma organochlorine concentrations might be associated with the decrease in serum T(3) concentration and RMR observed in response to body weight loss. Plasma organochlorine concentrations, serum T(3) concentration, and RMR were measured before and after weight loss in 16 obese men who followed a nonmacronutrient-specific energy-restricted diet for 15 weeks. As expected, a significant decrease in serum T(3) concentration and RMR was observed after the program, whereas concentrations of most detected organochlorines were significantly increased. Changes in organochlorine concentrations were negatively associated with changes in serum T(3) concentration (significantly for p,p'-DDT, HCB, Aroclor 1260, PCB 28, PCB 99, PCB 118, and PCB 170) and with changes in RMR adjusted for weight loss (significantly for HCB and PCB 156). In conclusion, organochlorines released in plasma during weight loss are associated with the documented decrease in serum T(3) concentration and RMR. Further studies are needed to verify whether these findings are causally related.