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1.
Circulating concentrations of albumin and the labile proteins prealbumin (PA) and retinol-binding protein (RBP) were evaluated over 20 d in five groups of obese patients. The patients were given four types of very-low-calorie diets (VLCDs) (less than 500 kcal/d) that provided different amounts of protein or carbohydrate (CHO) plus protein and a conventional 1200-kcal/d hypocaloric diet. Serum albumin concentrations did not vary significantly during any of the diets whereas PA and RBP remained unchanged only during the conventional 1200-kcal/d diet. Similar and significant decreases of serum PA and RBP were observed during the VLCDs studied. The molar ratio of RBP to PA did not vary during dieting. Thus, when less than 500 kcal/d are given, changes of serum short-half-life visceral proteins are not affected by either the addition of CHO to protein or the changes in protein intake. Moreover, serum albumin concentration and RBP/PA do not vary during VLCDs.  相似文献   

2.
This study examined the effects of calorie alternation and exercise on weight loss. Moderately obese women (130-160% of ideal body weight) were randomly assigned to an alternating- or constant-calorie diet with or without aerobic exercise. Both diets provided an average of 1200 kcal/d over a 12-wk period; daily intake of subjects in the alternating-diet condition varied in a prescribed pattern from 600 to 1800 kcal/d. Exercising subjects walked 5 d/wk. All subjects participated in an intensive outpatient behavior-modification program. At the end of the study, exercised subjects had greater reductions in body weight and body fat percentage than did nonexercised subjects. The type of caloric restriction did not affect weight or fat loss. Changes in resting metabolic rate did not differ among groups. Alternating calories was neither beneficial nor detrimental as a weight-loss strategy whereas exercise was clearly beneficial in weight-loss therapy.  相似文献   

3.
A comparative assessment was made of the short-term effects of orlistat therapy and exercise training on body composition and aerobic fitness in obese females. A total of 24 obese patients were enrolled in to the study; 12 received orlistat therapy (DO) and 12 participated in a regular aerobic exercise-training programme (DE). All patients were on hypocaloric diets. Each patient performed three incremental ramp exercise tests (one at Week 0, one at the end of Week 4 and one at the end of Week 8) to exhaustion using an electromagnetically braked cycle ergometer to determine their anaerobic threshold and maximal exercise (Wmax) capacity. Patients in the DE group performed continuous exercise at a work rate that corresponded to the anaerobic threshold. Weight loss and loss of fat mass after 8 weeks were -6.4% (P=0.002) and -13.4% (DE) vs -5.8% (P=0.002) and -6.4% (P=0.008) (DO), respectively. Wmax capacity was 90.8+/-5 W (basal) vs 92.9+/-5 W (Week 4, P=0.1) and 100.4+/-6 W (Week 8, 10.5%, P=0.04) in the DO group, and 96.2+/-6 W (basal) vs 129.1+/-4 W (Week 4, 34.1%, P=0.002) and 137.5+/-5 W(Week 8, 42.9%, P=0.002) in the DE group. Despite similar decreases in body weight in both groups, patients in the DE group achieved a markedly higher level of Wmax, reflecting a better improvement in cardiopulmonary fitness, compared with patients in the DO group. Considering the improvement of aerobic fitness in the short term, an aerobic exercise-training programme should be considered for sedentary obese patients to improve their aerobic fitness and thereby reduce the negative outcomes of obesity.  相似文献   

4.
Body composition, maximal aerobic power (VO2 max), resting metabolic rate (RMR), and lipolytic activity of abdominal adipocytes were measured in 20 women (body mass index [BMI] = 33.5) during 14 wk of exercise training (4 h/wk at 60% of VO2 max) and dietary restriction (840 kcal/d). Frequent dieters (yo-yo) and women without a dietary history (non-yo-yo) were matched into the following groups: diet-exercise yo-yo (DE-Y), diet-exercise non-yo-yo (DE-NY), and diet-non-yo-yo group (D-NY). After 14 wk significant differences in weight loss and fat loss were revealed between D and DE groups but not between yo-yo and non-yo-yo dieters. RMR decreased in all groups but there was a significantly smaller decline after 14 wk for the diet-exercise groups. No effects of frequent dieting or exercise on basal and stimulated lipolytic activity were observed.  相似文献   

5.
Calorie-restricted low-fat diet and exercise in obese women   总被引:4,自引:0,他引:4  
The effects of caloric restriction and exercise on body composition, resting metabolic rate (RMR), and maximal oxygen uptake (VO2 max) were studied for 16 wk in 26 premenopausal obese women. Exercise (X) vs nonexercise (NX) was crossed with a low-fat, ad libitum-carbohydrate (AL) diet vs a restricted (R) (800 kcal) low-fat, high-carbohydrate diet in a 2 x 2 factorial design. Subjects were randomly assigned to one of the four treatment groups. Body-weight and percent-fat losses were significant (p less than 0.05) in all groups but greater in subjects assigned to the R diet (p less than 0.05) and/or X (p less than 0.10) groups. Exercise increased (p less than 0.01) VO2 max but neither exercise nor diet influenced fat-free mass or RMR (kcal.m-2.h-1), both of which remained unchanged over time. A program similar to that followed by the ALX group is recommended for long-term weight control and overall health.  相似文献   

6.
In this study, six obese women received a very-low-calorie diet (VLCD) for 3 wk. At day 0, body composition was assessed with a bioelectric impedance analyzer. The evolution in lean body mass (LBM) during the VLCD was estimated from nitrogen balance, measuring urine and fecal losses and taking into account skin, nitrate, and menstrual losses to avoid underestimation bias that could explain the decreased ratio of resting metabolic rate (RMR) to LBM previously reported. RMR was measured at days 0, 3, 5, and 21. The RMR-LBM ratio declined significantly during the VLCD period and decreased faster during the first week; the day 3, day 5, and day 21 ratio values were 94%, 91%, and 82%, respectively, of the original. The RMR-LBM ratio decrease after 21 d of a VLCD was near that found in chronic undernutrition. Results of previous studies that did not find any drop in the RMR-LBM ratio in obese adults on VLCDs might be explained by their LBM-assessment methods.  相似文献   

7.
A 4-6 mo study was conducted to examine effects of a very-low-calorie, high-protein diet and realimentation on energy expenditure, resting metabolic rate (RMR), and serum thyroid hormones of obese women aged 30-54 yr. Fifteen healthy women, greater than or equal to 126% ideal body weight, were placed on the diet (420 kcal/day) and lost an average of 1.1 kg/wk until a predetermined goal weight was attained. RMR, triiodothyronine (T3), and reverse T3 decreased significantly (p less than 0.05). Thyroxine remained unchanged. Upon gradual realimentation onto solid foods, all metabolic parameters increased significantly within 5 wk toward pre-diet baseline values, but RMR (kcal/h) and T3 values remained significantly below pre-study values. Estimates of mean energy expenditure, utilizing a technique based on energy intake and body composition changes, averaged 1719 kcal/day during the diet period.  相似文献   

8.
OBJECTIVE: We compared health outcomes in obese adults who underwent 12 wk of exercise counseling with or without dietary counseling, followed by 12 wk of observational monitoring. METHODS: Ninety adults (77 women and 13 men; 42.6 +/- 6.0 y; body mass index, 31.5 +/- 2.8 kg/m(2)) were randomly assigned to exercise-only (EX) or diet-plus-exercise (DEX) groups and counseled weekly by exercise physiologists on a 12-wk walking program. DEX subjects were also counseled by dietitians on a hypocaloric diet (-500 kcal/d). From weeks 12 to 24, subjects were monitored but not counseled. At weeks 0, 12, and 24, data collection included body composition (air displacement plethysmography), fitness (maximum oxygen consumption, 3-min step-test, and timed mile), plasma lipids, weight loss efficacy (Weight Efficacy Life-Style Questionnaire), quality of life (Medical Outcomes Study Health Survey-Short Form 36), and mood (Profile of Mood States). RESULTS: At 12 and 24 wk, weight and body mass index decreased in DEX subjects (both P < 0.05) but not in EX subjects. However, lean body mass increased significantly in EX (24 wk, P < 0.05) but not in DEX subjects. In both groups, fat mass decreased (P < 0.05 for EX subjects at 24 wk; P < 0.05 for DEX subjects at 12 and 24 wk) and waist circumference decreased (P < 0.05 for EX subjects at 12 and 24 wk; P < 0.05 for DEX subjects at 12 and 24 wk). At 12 and 24 wk, DEX subjects showed decreased levels of total plasma cholesterol and triacylglycerols (both P < 0.05) and improvements with regard to the Weight Efficacy Life-Style Questionnaire (P < 0.05), three domains of the Medical Outcomes Study Health Survey-Short Form 36 (all P < 0.05), and three domains of the Profile of Mood States (all P < 0.05) that were not seen in EX subjects. CONCLUSIONS: Exercise counseling for 12 wk in obese adults improves some body composition indices that can be sustained over 12 wk of monitoring. The addition of dietary counseling increases improvements in body composition, lipid profiles, and several psychological parameters.  相似文献   

9.
OBJECTIVE: To determine the impact of diet-induced weight loss on cardiac autonomic nervous system modulation and arrhythmias in subjects with severe obesity and the influence of a high-fat or a high-carbohydrate diet regimen on heart rate variability in reduced-obese individuals. RESEARCH METHODS AND PROCEDURES: Eight severely obese subjects (BMI > or = 40.0 kg/m(2)) underwent a 3-month weight loss program followed by a 3-month reduced-weight maintenance regimen. Thereafter, each subject was admitted for an inpatient period of 17 days on two separate occasions. A high-carbohydrate (60%) or high-fat (55%) diet of appropriate energy content for weight maintenance was prescribed during each inpatient phase. Heart rate variability was derived from a 24-hour Holter monitoring system in all subjects during their inpatient stay. Cardiac Holter monitoring was performed at three occasions (baseline, diet phase I, and diet phase II), including the second night of a two overnight calorimetry chamber stay. RESULTS: After the diet regimen, there was a 10% decrease in weight. There were no significant changes in systolic and diastolic blood pressure, arrhythmias, glucose, insulin, total cholesterol, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, respiratory exchange ratio, and resting energy expenditure between experiments. Mean heart rate was lower after weight loss compared with baseline (p < 0.001). After weight loss, there was an increase in the parasympathetic indices of heart rate variability showing an increase in cardiac vagal modulation (all p < 0.05). DISCUSSION: Weight loss is associated with significant improvement in autonomic cardiac modulation through enhancement of parasympathetic modulation, which clinically translates into a decrease in heart rate.  相似文献   

10.
Fifteen premenopausal obese women, seven abdominal obese (AO) and eight gluteal-femoral obese (GFO), followed an energy-reduced diet of 1000 kcal/d (4.2 MJ/d) over 8 wk. Body-fat distribution was assessed using a cutoff point of 0.80 for the waist-to-hips girth ratio. Before and after the dietary treatment resting metabolic rate (RMR) and diet-induced thermogenesis (DIT) (after a normal breakfast) were measured by indirect calorimetry. Body-weight reduction and energy intake during the diet period did not differ significantly between both groups. Before weight loss the AO group had slightly greater RMR than the GFO group. After weight loss mean RMR decreased about 10% in the AO group and about 2.5% in the GFO group. Before weight loss DIT was slightly but not significantly higher in the AO group than in the GFO group. After weight loss DIT increased significantly in the GFO group. Weight loss was generally associated with decreased blood glucose, serum triglycerides, and total serum cholesterol levels in the AO women but not in the GFO women.  相似文献   

11.
To assess the individual and combined effects of weight loss and weight training on body weight and body composition, 40 obese women were randomly assigned to one of four groups for an 8 wk weight-loss study. These groups were control (C); diet without exercise (DO); diet plus weight training (DPE); and weight training without diet (EO). Body weight decreased for DO (-4.47 kg) and DPE (-3.89 kg) compared with C (-0.38 kg) and EO (0.45 kg). Lean body weight (LBW) increased for EO (1.07 kg) compared with DO (-0.91 kg) and C (-0.31 kg) and for DPE (0.43 kg) compared with DO. Upper-arm muscle areas (determined by radiograph) increased for DPE (11.2 cm2) and EO (10.4 cm2) compared with C (2.7 cm2) and DO (2.1 cm2). It was concluded that weight training results in comparable gains in muscle area and strength for DPE and EO. Adding weight training exercise to a caloric restriction program results in maintenance of LBW compared with DO.  相似文献   

12.
Resting energy expenditure (REE), maximum oxygen uptake (VO2max), and body composition were measured in seven moderately obese women during 9 wk of dietary restriction (800 kcal/d). During weeks 4-6, subjects underwent exercise training (30 min cycling/d, 5 d/wk, at 70% VO2max). The first 3 wk of caloric restriction decreased REE by 13% (from 1437 +/- 76 to 1254 +/- 66 kcal/24 h, means +/- SEM, p less than 0.05). Exercise training increased VO2max (from 1717 +/- 108 to 1960 +/- 120 mL/min, means +/- SEM, p less than 0.05) but did not elevate the dietary-depressed REE (from 1254 +/- 66 to 1262 +/- 62 kcal/24 h). The greatest decrease in body fat (3.7 +/- 0.4 kg) occurred during exercise training, resulting in a small apparent increase in REE when expressed per kilogram total body weight. However, expressed per unit lean body mass, REE remained suppressed throughout the period of caloric restriction. We conclude that exercise training of sufficient intensity to substantially increase VO2max does not reverse the dietary-induced depression of REE.  相似文献   

13.
ObjectiveVery-low-calorie diets (VLCDs) are an effective method for weight reduction in Caucasians. This study investigated the efficacy and safety of two different VLCDs (450 or 800 kcal/d) in obese Taiwanese.Methods132 participants with BMI ≥30 kg/m2 were randomized to two VLCD groups for body weight reduction for 12 weeks. Each group had 66 participants. Anthropometric and metabolic parameters were measured.ResultsThe intention-to-treat analysis revealed that the percentage change in body weight over the 12-week treatment period was –9.14% in the VLCD-450 group and –8.98% in the VLCD-800 group. A total of 27 (40.9%) participants in the VLCD-450 group and 29 (43.9%) participants in the VLCD-800 group achieved 10% or more weight loss at the end of treatment. The body weight, waist circumference, hip circumference, fat mass, blood pressure, triglycerides, and blood glucose were statistically improved from baseline but not between the two groups. The improvement rate of nonalcoholic fatty liver disease (NAFLD) was 41.5% in the VLCD-450 group and 50.0% in the VLCD-800 group. The incidence of adverse events did not differ significantly between the groups and no serious adverse events were reported in either group.ConclusionBoth the VLCD-450 and 800 kcal/d can effectively and safely reduce body weight and improve NAFLD in 12 weeks in obese Taiwanese participants. However, there is no additional benefit in prescribing the more restrictive diet intervention in Taiwanese.  相似文献   

14.
BACKGROUND: There is little information on whether bioelectrical impedance analysis (BIA) accurately predicts changes in body composition associated with energy restriction, exercise, or both. OBJECTIVE: We had 2 objectives: to determine the validity of the leg-to-leg BIA system in 1) estimating body composition in obese and nonobese women, with a cross-sectional design, and 2) assessing changes in body composition in obese women in response to 12 wk of energy restriction, exercise training, or both. DESIGN: Subjects were 98 moderately obese women (43.2 +/- 0.6% body fat, 45.0 +/- 1.1 y of age) and 27 nonobese control subjects (24.0 +/- 1.5% body fat, 43.5 +/- 2.5 y of age). Obese subjects were randomly divided into 1 of 4 groups, with fat-free mass, fat mass, and percentage body fat estimated with BIA and underwater weighing before and after 12 wk of intervention. The 4 groups were diet only (4.19-5.44 MJ/d), exercise only (five, 45-min sessions/wk at 78.5 +/- 0.5% of maximum heart rate), both exercise and diet, and control (no diet or exercise). RESULTS: No significant difference was found between underwater weighing and BIA in estimating the fat-free mass of the obese and nonobese women (all subjects combined, r = 0.78, P < 0.001, SEE = 3.7 kg) or in estimating decreases in fat mass during 12 wk of energy restriction, exercise, or both in obese subjects (F[3.85] = 1.45, P = 0.233). CONCLUSIONS: The leg-to-leg BIA system accurately assessed fat-free mass in obese and nonobese women, and changes in fat mass with diet alone or when combined with exercise.  相似文献   

15.
Although a very-low-calorie diet (VLCD) is considered safe and has demonstrated benefits among other types of diets, data are scarce concerning its effects on improving health and weight loss in severely obese patients. As part of the personalized weight loss program developed at the Duga Resa Special Hospital for Extended Treatment, Croatia, we evaluated anthropometric, biochemical, and permanent DNA damage parameters (assessed with the cytochalasin B-blocked micronucleus cytome assay—CBMN) in severely obese patients (BMI ≥ 35 kg m−2) after 3-weeks on a 567 kcal, hospital-controlled VLCD. This is the first study on the permanent genomic (in)stability in such VLCD patients. VLCDs caused significant decreases in weight (loss), parameters of the lipid profile, urea, insulin resistance, and reduced glutathione (GSH). Genomic instability parameters were lowered by half, reaching reference values usually found in the healthy population. A correlation was found between GSH decrease and reduced DNA damage. VLCDs revealed susceptible individuals with remaining higher DNA damage for further monitoring. In a highly heterogeneous group (class II and III in obesity, differences in weight, BMI, and other categories) consisting of 26 obese patients, the approach demonstrated its usefulness and benefits in health improvement, enabling an individual approach to further monitoring, diagnosis, treatment, and risk assessment based on changing anthropometric/biochemical VLCD parameters, and CBMN results.  相似文献   

16.
The effect of caloric restriction (1200 kcal/d intake) in combination with high (High) (80-90% of peak VO2) or low (Low) (40-50% of peak VO2) exercise work rates on the composition of lost body mass was determined in 27 obese women (percent fat, 36.7 +/- 4.2%; mean +/- SD). All subjects trained 3 d/wk for 8 wk, with the High (n = 14) and Low (n = 13) groups exercising for 25 and 50 min/d, respectively. After posttesting there were no differences between the groups with respect to pre- to posttest changes (mean of combined groups) in body mass (-7%), fat-free mass (-10%), fat mass (-16%), percent fat (-10%), and sum of five skinfold-thickness measurements (-16%). This study suggests that with regard to conservation of fat-free mass, the selection of an exercise intensity for a diet and exercise regimen may be left to the preference of the clinician and/or dieter.  相似文献   

17.
BACKGROUND: Energy restriction is known to induce a decline in fat oxidation during the postdiet period. Reduced fat oxidation may contribute to weight regain. OBJECTIVE: The present study investigated the effect of the addition of low-intensity exercise training to energy restriction on postdiet fat oxidation and on the contribution of the sympathetic nervous system to fat oxidation. DESIGN: Forty obese men were divided randomly into 2 groups: diet (D) and diet plus exercise (DE). Both groups followed an energy restriction program for 10 wk. Subjects in the DE group also participated in a low-intensity exercise training program [40% maximal oxygen uptake (VO2max)] for 12 wk. Before the intervention and after 12 wk, with subjects at stable body weights, we measured body composition, VO2max, and substrate oxidation at rest, during exercise at 50% VO2max, and during recovery. Measurements were made with and without administration of the beta-adrenergic antagonist propranolol. RESULTS: Both interventions led to significant decreases in body weight, fat mass, and fat-free mass (P < 0.001); these decreases did not differ significantly between the D and DE groups. Neither intervention significantly affected VO2max. The effect of the intervention on the respiratory exchange ratio differed significantly between the D and DE groups [two-way analysis of variance (ANOVA), P < 0.05]. The effect on the beta-adrenergic-mediated respiratory exchange ratio tended to be different between the 2 groups (two-way ANOVA, P = 0.09). CONCLUSION: Addition of low-intensity exercise training to energy restriction counteracts the decline in fat oxidation during the postdiet period.  相似文献   

18.
OBJECTIVE: We investigated the effect of hypocaloric mixed diets with different proportions of carbohydrate, protein, and fat on resting metabolic rate and the thermic effect of food in obese women. METHODS: Three mixed hypocaloric diets were consumed in random order during separate periods lasting 7 d each. Between each dietary period there was a washout period of 10 d. Diet 1 had a higher proportion of energy from carbohydrate (72%), diet 2 had a higher proportion of energy from protein (43%), and diet 3 had a higher proportion of energy from fat (68%). Indirect calorimetry and lung function tests were done after the completion of each 7-d diet. Seven obese women, ages 22 to 45 y and with body mass indexes of 32 to 59 kg/m(2), participated in the study. Oxygen consumption, carbon dioxide production, resting metabolic rate, and the thermic effect of food by indirect calorimetry were measured. Lung function tests included spirometry in the seated and upright positions, arterial blood gas analysis, and maximal inspiratory and expiratory pressures. RESULTS: There were no statistically significant differences in the resting metabolic rate and the thermic effect of food resulting from the three diets. The mean resting metabolic rates (kJ/d) were 7453 +/- 1446 for diet 1, 7461 +/- 1965 for diet 2, and 7076 +/- 2048 for diet 3. The mean thermic effects of food (kcal/min) were -0.02 +/- 0.07 for diet 1, -0.01 +/- 0.25 for diet 2, and 0.05 +/- 0.13 for diet 3. Lung function tests were normal before and after the hypocaloic diets: partial pressure of oxygen (mmHg) values were 81 +/- 13, 77 +/- 8, and 78 +/- 11 for diets 1 to 3, respectively; and partial pressure of carbon dioxide (mmHg) were 37 +/- 4, 37 +/- 3, and 37 +/- 4 for diets 1 to 3, respectively. CONCLUSIONS: Obese women with normal lung function tests and consuming mixed hypocaloric diets showed no alteration in resting metabolic rate and a reduced or absent thermic effect of food independently of the macronutrient composition.  相似文献   

19.
BACKGROUND: Some investigators fear that dieting may precipitate binge eating and other adverse behavioral consequences. OBJECTIVE: The objective of the study was to examine whether dieting would elicit binge eating and mood disturbance in individuals free of these complications before treatment. DESIGN: A total of 123 obese women were randomly assigned to 1) a 1000 kcal/d diet that included 4 servings/d of a liquid meal replacement (MR); 2) a 1200-1500 kcal/d balanced deficit diet (BDD) of conventional foods; or 3) a nondieting (ND) approach that discouraged energy restriction. All women attended weekly group sessions for 20 wk and biweekly sessions from week 20 to week 40. RESULTS: At week 20, participants in the MR, BDD, and ND groups lost 12.1 +/- 6.7%, 7.8 +/- 6.0%, and 0.1 +/- 2.4% of initial weight, respectively (P < 0.001). During the first 20 wk, there were no significant differences among groups in the number of persons who had objective binge episodes or in reports of hunger or dietary disinhibition. Symptoms of depression decreased significantly more (P < 0.001) in the MR and BDD groups than in ND participants. At week 28, significantly more (P < 0.003) cases of binge eating were observed in MR participants than in the 2 other groups. No differences, however, were observed between groups at weeks 40 or 65 (a follow-up visit). At no time did any participant meet criteria for binge-eating disorder. CONCLUSION: Concerns about possible adverse behavioral consequences of dieting should not dissuade primary care providers from recommending modest energy restriction to obese individuals.  相似文献   

20.
目的探讨劳累性心绞痛患者中,静息心电图正常的发生率厦产生原因。方法205例经冠状动脉造影证实为冠状动脉病变的劳累性心绞痛患者,分为心电图异常组和心电图正常组,对心电图正常组患者进行体袁心电图、Hoher、平板运动试验检查。结果静息心电图正常者83例,其中Holter检查ST—TCMV5呈缺血型者23例,平板运动试验阳性厦可疑阳性共46例,单支冠状动脉轻度狭窄和三支冠状动脉重度狭窄并侧支循环病例中。心电图正常组的例数多于心电图异常组(P均〈0.05)。静息心电图正常的劳累性心绞痛发生率为40.48%。结论病变冠状动脉主要在单支轻度狭窄及三支重度狭窄并侧支循环血管。  相似文献   

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