The effect of body weight changes and endurance training on 24 h substrate oxidation

The effect of body weight changes and endurance training on 24h substrate oxidation. Pasman WJ, Westerterp MS, Saris WH. Maastricht University, Department of Human Biology, The Netherlands. [email protected] OBJECTIVE: To investigate the effect of exercise training and dietary macronutrient composition on 24 h substrate oxidation in male, obese subjects. DESIGN: A 16 month exercise intervention study was executed, including a weight loss period with a very low energy diet (VLED) for 2 months at the start of the study. SUBJECTS: Twelve male, obese subjects (age 36.3+/-5.1 y; body weight 94.6+/-13.9 kg; body mass index, BMI 30.8+/-3.0 kg/m2) and in an additional study 15 lean, well-trained subjects (age 36.2+/-7.2 y; body weight 72.2+/-5.9 kg; BMI 22.3+/-1.7 kg/m2) participated. MEASUREMENTS: Substrate oxidation was measured during a standardized 36 h stay in the respiration chamber at the start of the study (0 months), and at 4, 10 and 16 months. In the respiration chamber subjects were randomly assigned to a high-fat (Hi.F) diet (60% of energy (En%) fat) or a reduced-fat (Red.F) diet (30 En% fat). The well-trained group was measured once in the respiration chamber for 36 h according to the same protocol. RESULTS: At any time point, independent of the diet consumed, the 24 h carbohydrate (CHO) balances in the chamber were mostly negative (means ranging from +31 to -98 g/d) and the fat balances mostly positive (means ranging from -26 to +38 g/d) for the obese a well as for the lean, well-trained group. For both diets an increased shortage of 70 g of CHO was found at 16 months compared with 4 months, and an increase in fat balance of 33 g during the same time period in the obese subjects, indicating that CHO oxidation had increased with 12 months endurance training. In the well-trained group the 24h CHO balance was even more negative for both types of diet (-103 to -185 g/d for the Red.F and Hi.F diet, respectively) under similar conditions compared with the trained obese group. CONCLUSION: The changes in 24 h substrate utilization in the obese, as well as in the well-trained group, suggest that endurance training increased the reliance on carbohydrate oxidation and therefore did not increase 24 fat oxidatio

Moderate energy restriction with high protein diet results in healthier outcome in women

BACKGROUND: The present study compares two different weight reduction regimens both with a moderately high protein intake on body composition, serum hormone concentration and strength performance in non-competitive female athletes. METHODS: Fifteen normal weighted women involved in recreational resistance training and aerobic training were recruited for the study (age 28.5 ± 6.3 yr, height 167.0 ± 7.0 cm, body mass 66.3 ± 4.2 kg, body mass index 23.8 ± 1.8, mean ± SD). They were randomized into two groups. The 1 KG group (n = 8; energy deficit 1100 kcal/day) was supervised to reduce body weight by 1 kg per week and the 0.5 KG group (n = 7; energy deficit 550 kcal/day) by 0.5 kg per week, respectively. In both groups protein intake was kept at least 1.4 g/kg body weight/day and the weight reduction lasted four weeks. At the beginning of the study the energy need was calculated using food and training diaries. The same measurements were done before and after the 4-week weight reduction period including total body composition (DXA), serum hormone concentrations, jumping ability and strength measurements RESULTS: During the 4-week weight reduction period there were no changes in lean body mass and bone mass, but total body mass, fat mass and fat percentage decreased significantly in both groups. The changes were greater in the 1 KG group than in the 0.5 KG group in total body mass (p < 0.001), fat mass (p < 0.001) and fat percentage (p < 0.01). Serum testosterone concentration decreased significantly from 1.8 ± 1.0 to 1.4 ± 0.9 nmol/l (p < 0.01) in 1 KG and the change was greater in 1 KG (30%, p < 0.001) than in 0.5 KG (3%). On the other hand, SHBG increased significantly in 1 KG from 63.4 ± 17.7 to 82.4 ± 33.0 nmol/l (p < 0.05) during the weight reducing regimen. After the 4-week period there were no changes in strength performance in 0.5 KG group, however in 1 KG maximal strength in bench press decreased (p < 0.05) while endurance strength in squat and counter movement jump improved (p < 0.05) CONCLUSION: It is concluded that a weight reduction by 0.5 kg per week with ~1.4 g protein/kg body weight/day can be recommended to normal weighted, physically active women instead of a larger (e.g. 1 kg per week) weight reduction because the latter may lead to a catabolic state. Vertical jumping performance is improved when fat mass and body weight decrease. Thus a moderate weight reduction prior to a major event could be considered beneficial for normal built athletes in jumping events.peerReviewe

Randomized, multi-center trial of two hypo-energetic diets in obese subjects: high- versus low-fat content

Objective:To investigate whether a hypo-energetic low-fat diet is superior to a hypo-energetic high-fat diet for the treatment of obesity.Design:Open-label, 10-week dietary intervention comparing two hypo-energetic (-600 kcal/day) diets with a fat energy percent of 20-25 or 40-45.Subjects:Obese (BMI >/=30 kg/m(2)) adult subjects (n=771), from eight European centers.Measurements:Body weight loss, dropout rates, proportion of subjects who lost more than 10% of initial body weight, blood lipid profile, insulin and glucose.Results:The dietary fat energy percent was 25% in the low-fat group and 40% in the high-fat group (mean difference: 16 (95% confidence interval (CI) 15-17)%). Average weight loss was 6.9 kg in the low-fat group and 6.6 kg in the high-fat group (mean difference: 0.3 (95% CI -0.2 to 0.8) kg). Dropout was 13.6% (n=53) in the low-fat group and 18.3% (n=70) in the high-fat group (P=0.001). Among completers, more subjects lost >10% in the low-fat group than in the high-fat group ((20.8%, n=70) versus (14.7%, n=46), P=0.02). Fasting plasma total, low-density lipoprotein- and high-density lipoprotein-cholesterol decreased in both groups, but more so in the low-fat group than in the high-fat group. Fasting plasma insulin and glucose were lowered equally by both diets.Conclusions:The low-fat diet produced similar mean weight loss as the high-fat diet, but resulted in more subjects losing >10% of initial body weight and fewer dropouts. Both diets produced favorable changes in fasting blood lipids, insulin and glucose.International Journal of Obesity advance online publication, 6 December 2005; doi:10.1038/sj.ijo.0803186

Dietary factors impact on the association between CTSS variants and obesity related traits.

Cathepsin S, a protein coded by the CTSS gene, is implicated in adipose tissue biology--this protein enhances adipose tissue development. Our hypothesis is that common variants in CTSS play a role in body weight regulation and in the development of obesity and that these effects are influenced by dietary factors--increased by high protein, glycemic index and energy diets

Points-based physical activity: a novel approach to facilitate changes in body composition in inactive women with overweight and obesity

Background Physical activity (PA) interventions for the promotion of weight-management may benefit from increased choice and flexibility to overcome commonly-perceived barriers to PA. The aim of this study was to investigate the effects of a novel “points-based” approach to PA on body composition in inactive women, who are overweight or obese. Methods Seventy-six overweight or obese, inactive women were randomly allocated to one of three conditions: ‘Points-based’ PA (PBPA; 30 “PA points”•week− 1), Structured exercise (StructEx; 150 min moderate-intensity exercise•week− 1) or control (CONT; continue habitual inactive lifestyle) for a 24-week intervention. PA points for activities were adapted from MET values, and 30 points was equivalent to 150 min of brisk walking. Measures of body composition (dual-energy x-ray absorptiometry) and anthropometry were obtained at weeks 0, 4, 12 and 24. Self-report activities were recorded weekly, with objective measures of PA (tri-axial accelerometry) and self-report measures of food intake obtained at weeks 0 and 24. Results Fifty-eight women completed the study and provided data for primary outcomes. Of these, n = 41 and n = 19 provided data for food intake and objectively assessed PA. Mixed-design ANOVAs demonstrated that those in PBPA achieved a significant weight-loss at 24 weeks of − 3.3 ± 5.9 kg (− 3.4 ± 7.1%, p = 0.004). Waist circumference was reduced in PBPA at 24 weeks (− 2.8 ± 4.6 cm), compared with CONT (+ 2.1 ± 6.6 cm, p = 0.024). There was a trend for greater reductions in fat mass for those in PBPA vs. CONT (− 2.3 ± 4.6 kg vs. + 0.1 ± 2.0 kg, p = 0.075). Android fat was reduced in PBPA at both 12 weeks (− 6.1 ± 12.6%, p = 0.005) and 24 weeks (− 10.1 ± 18.4%, p = 0.005), while there was a trend for greater reductions in visceral adipose tissue in PBPA (− 5.8 ± 26.0%) vs. CONT at 24 weeks (+ 7.8 ± 18.3%, p = 0.053). Body composition, body weight and waist circumference were unchanged in StructEx. There were trends for increases in light-activity and reductions in sedentary time in PBPA. There was a trend for a reduction in daily energy intake of − 445 ± 564 kcal (p = 0.074), and a significant reduction in daily fat intake (p = 0.042) in PBPA. Conclusion A “points-based” approach to physical activity appears to be an effective strategy for inducing modest reductions in body weight and body fat in inactive women with overweight and obesity

The effectiveness of long-term supplementation of carbohydrate, chromium, fibre and caffeine on weight maintenance

Department of Human Biology, Maastricht University, The Netherlands. [email protected] OBJECTIVE: To investigate whether supplementation of carbohydrate, chromium, dietary fibre and caffeine is effective for maintenance of weight-loss in the long-term. DESIGN: A longitudinal, double-blind, randomly assigned intervention study of 16 months with supplementation of either 50g of carbohydrates (CHO), 200 micrograms chromium-picolinate (Cr-Pic), 20g of soluble fibre plus 100 mg caffeine (CHO+) or 50g of plain CHO, for 16 months besides a very low energy diet (VLED) during the first two months. SUBJECTS: Thirty-three female obese subjects (age, 34.8 +/- 7.0 y; body weight (BW): 85.5 +/- 10.0 kg; body mass index (BMI) 31.2 +/- 3.7 kg.m-2) participated, 13 subjects were supplemented with CHO+, 11 subjects were supplemented with CHO and 9 subjects served as a control group. MEASUREMENTS: SW, body composition, energy intake and blood parameters were measured before the VLED (0), after the VLED at 2 months (2), and at 4, 10 and 16 months. RESULTS: The amount and course of relapse of BW was equal for the supplemented and control groups. The average regain at 16 months (the weight gained as a percentage of the total weight loss during the VLED) was 66.1 +/- 81.2%, and was not different between the groups. No differences in body composition were found between the groups at 16 months. The CHO supplements resulted in significantly elevated energy percentage (En %) intake of CHO daily, in both supplemented groups, although this did not result in less regain. Pearson correlation analysis for all subjects revealed that the more fat consumed, the more regain was found at 16 months (r = 0.41, P < 0.05). A high CHO consumption was correlated with less regain (r = -0.40, P = 0.05). Furthermore, chromium intake did not result in significant changes in blood parameters and body composition. CONCLUSION: Although additional supplementation of CHO, chromium, dietary fibre and caffeine intake did not affect BW, the En % CHO daily was increased significantly. Our results indicate that a high En% intake of CHO and a low En% intake of fat daily is beneficial for prevention of weight regain. Publication Types: Clinical Trial Randomized Controlled Tria