Total Body Fat Tissue Mass Research Articles

Effect of body composition on bone mineral density in Moroccan patients with juvenile idiopathic arthritis.

IntroductionThe link between bone mass and body composition is widely recognized, but only few works were selectively performed on subjects with juvenile idiopathic arthritis. The aim of our study was to investigate the effect of body composition on bone mineral density (BMD) in Moroccan patients with juvenile idiopathic arthritis.MethodsThirty three children with juvenile idiopathic arthritis (JIA) were included in a cross-sectional study. The diagnosis of JIA was made according to the criteria of the International League of Association of Rheumatology (ILAR). Body mass index (BMI) was calculated from the ratio of weight/height2(kg/m2). Pubertal status was determined according to the Tanner criteria. Bone status, body composition and bone mineral content (BMC) were analyzed by using dual-energy X-ray absorptiometry (DXA). BMD was assessed at the lumbar spine (L1-L4) and at total body in (g/cm2). Total body fat tissue mass (FTM) and lean tissue mass (LTM) were also analyzed by DXA and expressed in kilograms. In children, low BMD was defined as a Z-score less than -2 and osteoporosis was defined as a Z-score less than -2 with a fracture history.ResultsA cross-sectional study was conducted in 33 Moroccan patients with JIA aged between 4 and 16 years, Fat mass was not related to bone density; in contrast, BMD was positively associated to LTM in total body(r = =0.41, p= 0.04) but not in lumbar spine (r = 0.29, p= 0.17). There exist significant correlation between BMC and BMD in total body (r = 0.51, p = 0.01).ConclusionThis study suggests that the LTM is a determining factor of the BMD during adolescence. Other studies with a broader sample would be useful to confirm this relation.

DEXA-assessed regional body composition changes in young female military soldiers following 12-weeks of periodised training

Dual-energy X-ray absorptiometry (DEXA) was used to assess whole body and regional soft tissue mass, fat mass and lean body mass compositional changes in 68 female recruits (age 20.8 ± 1.14 years; body mass 59.5 ± 8.79 kg; stature 159.57 ± 5.53 cm) pre- and post 12-weeks of military basic training. A decrease in total body fat tissue mass (10.2%) and regional percent fat (10.9%) was measured with an increase in total lean body mass (8.7%). Of interest were the differences in the responses in the tissue composition of the arms (16.2% loss in fat mass with an 11.6% gain in lean mass), trunk (17.0% decrease in fat mass with a 10.4% increase in lean mass) and the legs (10.5% increase in lean mass but no change in fat mass). These findings show the importance of considering regional rather than whole body composition changes when assessing the effects of a training programme. Statement of Relevance: Female soldiers experienced a change in total body fat tissue (−10.2%) and lean body mass (+8.7%) after basic training; however, no significant fat mass decrease was evident in the leg region. Regional rather than whole body composition changes need to be considered when assessing the effects of a training programme.

Effect of climacteric transition and hormone replacement therapy on body weight and body fat distribution

In the present study we evaluated the effects of climacteric modifications on body weight and fat distribution. From women attending a menopause clinic we selected 2175 untreated, normal healthy women who were divided into three groups: premenopausal (n = 540), perimenopausal (n = 750) and postmenopausal (n = 885), and compared them with 354 postmenopausal women receiving different forms of hormone replacement therapy (HRT). The total body fat tissue mass and distribution were analyzed using dual-energy X-ray absorptiometry. Body weight and body mass index (BMI) were significantly higher in perimenopausal and postmenopausal than in premenopausal women. Mean total body fat and fat as a percentage of soft tissue were significantly (p < 0.05) higher in the perimenopausal and postmenopausal groups than in the premenopausal group. Fat tissue and regional fat tissue as a percentage of total fat tissue were higher in the trunk (p < 0.0001) and arms (p < 0.0001) in perimenopausal and postmenopausal than in premenopausal women. In postmenopuasal women, leg fat tissue was significantly (p < 0.05) lower than in premenopausal and perimenopausal groups. Total body and leg lean tissue were significantly lower (p < 0.05) in postmenopausal than in premenopausal and perimenopausal women. In age-matched women with similar BMI, total body fat as a percentage of soft tissue was significantly (p < 0.001) higher in the perimenopausal and postmenopausal groups than in the premenopausal group. As for body fat distribution, fat as a percentage of total fat tissue was significantly higher in the trunk (p < 0.0001) region in perimenopausal and postmenopausal women compared with the premenopausal group. In the legs, fat as a percentage of total fat tissue was significantly higher (p < 0.05) in the premenopausal than in the postmenopausal group. In the arms a slight but not significant (p < 0.18) difference was shown in fat distribution between the three untreated groups. In age-matched HRT-treated postmenopausal women, the fat tissue was similar to that in the premenopausal group. The present results confirm that endocrine changes during the menopausal transition, rather than the aging process, are related to changes in body weight and fat distribution. Perimenopausal and postmenopausal women show a shift to a central, android fat distribution that can be counteracted by HRT.

Influence of female and male sex steroids on body composition in the rabbit model

Objective To study the influence on body composition of estrogen replacement therapy (ERT) in female rabbits and of replacement therapy with testosterone (TRT) in male rabbits using dual-energy X-ray absorptiometry (DEXA). Methods Cholesterol-fed female and male rabbits receiving a weight-restricted diet (100 g/day) were used. Total lean tissue mass (LTM), total body fat tissue mass (FTM) and total tissue mass (TTM) were determined by DEXA at baseline, after which the animals were gonadectomized and treated with sex steroids. Soft body composition was then determined again after 30–31 weeks of treatment. Results Relative to controls, ERT with estradiol (E2) doses of 2 and 4 mg/day significantly increased LTM ( p < 0.001), whereas E2 0.5 and 1 mg/day had a neutral effect on LTM. The change in fat mass, however, was not statistically significant between groups. In male rabbits, compared with castrated control rabbits, LTM decreased in testosterone-treated animals (by 7–12%; p < 0.001) but FTM decreased relatively more (by 66–79%; p < 0.0001). In both genders, body weight correlated with TTM as determined by DEXA (r = 0.89–0.91, p < 0.0001). Conclusion In this in vivo model of growing rabbits, estrogen replacement significantly increased LTM in female animals, whereas testosterone replacement significantly decreased FTM in males, suggesting that soft body composition of both genders is significantly affected by replacement with sex steroids. Until comparable human data are available, it is speculated that similar changes in soft body composition may occur in humans treated with sex steroids.

Influence of female and male sex steroids on body composition in the rabbit model

Objective To study the influence on body composition of estrogen replacement therapy (ERT) in female rabbits and of replacement therapy with testosterone (TRT) in male rabbits using dual-energy X-rayabsorptiometry (DEXA).Methods Cholesterol-fed female and male rabbits receiving a weight-restricted diet (100 g/day) were used. Total lean tissue mass (LTM), total body fat tissue mass (FTM)and total tissue mass (TTM) were determined by DEXA at baseline, after which the animals were gonadectomized and treated with sex steroids. Soft body composition was then determined again after 30–31weeks of treatment.Results Relative to controls, ERT with estradiol (E2) doses of 2 and 4 mg/day significantly increased LTM ( p < 0.001), whereas E2 0.5 and 1 mg/dayhad a neutral effect on LTM. The change in fat mass, however, was not statistically significant between groups. In male rabbits, compared with castrated control rabbits, LTM decreased in testosterone-treatedanimals (by 7–12%; p < 0.001) but FTM decreased relatively more (by 66–79%; p < 0.0001). In both genders, body weight correlated with TTM as determined by DEXA (r= 0.89–0.91, p < 0.0001).Conclusion In this in vivo model of growing rabbits, estrogen replacement significantly increased LTM in female animals, whereas testosteronereplacement significantly decreased FTM in males, suggesting that soft body composition of both genders is significantly affected by replacement with sex steroids. Until comparable human data are available,it is speculated that similar changes in soft body composition may occur in humans treated with sex steroids.

Climacteric modifications in body weight and fat tissue distribution

Objective To estimate the effects of climacteric modifications on body weight and fat distribution.Methods From 8764 women attending the authors' Menopause Clinic, 1075 untreated, normal healthy women were selected and divided into three groups: premenopausal (n = 380), perimenopausal (n = 263) and postmenopausal (n = 432). The total body fat tissue mass and distribution were analyzed using the dual energy X-ray method.Results Body weight and body mass index (BMI) were significantly higher in perimenopausal and postmenopausal than in premenopausal women. The mean total body fat and the percentage of fat with respect to soft tissue were significantly (p < 0.05) higher in the perimenopausal and postmenopausal groups than in the premenopausal group. The amount of fat tissue and the regional fat percentage with respect to total fat tissue were higher in the trunk (p < 0.05) and arm (p < 0.05) regions in perimenopausal and postmenopausal than in premenopausal women. In the postmenopausal group, the leg fat tissue was significantly (p < 0.05) less than in the premenopausal and perimenopausal groups. Total body and leg lean tissue was significantly (p < 0.01) less in postmenopausal than in premenopausal and perimenopausal women. In the premenopausal group, body weight and BMI were positively correlated with age (r = 0.37 and r = 0.54, respectively). No significant correlations were observed in the perimenopausal group. In postmenopausal women, body weight and BMI were loosely correlated with age (r = 0.13 and r = 0.11, respectively).In three groups of 63 age-matched women, with similar BMI, the percentage of total body fat with respect to soft tissue was significantly (p < 0.001) higher in the perimenopausal and postmenopausal groups than in the premenopausal group. Regarding body fat distribution, the percentage of fat with respect to total fat tissue was significantly higher in the trunk (p < 0.001) region in perimenopausal and postmenopausal women than in premenopausal women. In the leg region, the percentage of fat with respect to total fat tissue was significantly (p < 0.05) higher in the premenopausal group than in the postmenopausal group. In the arm region, a slight but not significant (p < 0.08) difference was shown in fat distribution among the three groups.Conclusions Climacteric changes rather than the aging process are relevant for prediction of body weight and fat distribution, especially for perimenopausal and postmenopausal women, who show a shift to a central, android fat distribution.

Additional weight-bearing during exercise is more important than duration of exercise for anabolic stimulus of bone: a study of running exercise in female rats

Mechanical loading is necessary for maintenance of skeletal integrity, but the most effective type, intensity, and duration of exercise are not known. In vivo experiments have indicated that the strain generated by the stimulus is more important than the duration of the stimulus. To elucidate this question, we studied 5-month-old female Wistar rats exercised on a motor-driven exercise belt for 17 weeks, 5 days per week (average velocity 20 m/min). Group 1 served as controls, group 2 was trained for 30 min, group 3 was trained for 30 min with a 50-g backpack, and group 4 was trained for 15 min with a 50-g backpack. Total body bone mineral content (BMC), bone mass of the lower extremities (LEBMC), total body lean soft-tissue mass (LSTM), and total body fat-tissue mass (FTM) were measured by dual-energy absorptiometry (DXA) at 0, 6, and 17 weeks. The BMC increased more in group 4 than in controls (15% vs. 8%, p < 0.03). In the other two intervention groups, no significant increases of total body BMC occurred compared with controls, although a trend was observed (12%). The LEBMC increased significantly in all exercising groups after 17 weeks, being 16% in group 2, 15% in group 3, and 20% in group 4, compared with 6% in controls ( p < 0.05). The increase in LSTM after 6 weeks was most pronounced in group 3, at 20%, compared with 10% in the control group ( p < 0.001). After 6 weeks of exercising, group 3 showed the most pronounced decrease in FTM, amounting to 33%, compared with a 1% increase in group 1 ( p < 0.001). Biomechanical testing of the femoral neck and cylinders of the femoral cortex yielded a pattern similar to that observed in BMC measurements of the total body and lower extremities. Biomechanical testing of the fourth lumbar vertebrae yielded no significant differences among the four groups. We conclude that a short duration of exercise with additional weight-bearing using a backpack leads to the most pronounced effects on total body BMC and LEBMC. In all exercising groups, the regional effect on the LEBMC was more pronounced than the effect on total body BMC; this was also reflected in the biomechanical properties.

Impact of regional and total body composition and hormones on resting energy expenditure in overweight postmenopausal women

The independent impact of regional and total body composition and sex and thyroid hormone levels on resting energy expenditure (REE) was assessed in 121 healthy, overweight (body mass index [BMI], 25 to 42 kg/m 2), postmenopausal women (aged 49 to 58 years). REE was measured by indirect calorimetry with a ventilated hood, and the total, trunk, and peripheral body composition by dual-energy x-ray absorptiometry (DXA). Sex and thyroid hormone levels were also measured. REE correlated significantly ( P < .05) better with trunk lean tissue mass ([LTM] r = .61) than with total-body ( r = .53) or peripheral LTM ( r = .30). Trunk LTM ( R 2 = .37), total-body fat tissue mass ([FTM] R 2 = .04), androstenedione ( R 2 = .03), and total triiodothyronine ([T 3] R 2 = .02) were all significantly independently associated with REE. Together they explained 46% (model R 2) of the interindividual variation in REE, with a standard error of estimate (SEE) of 549 kJ/d. We conclude that the interindividual variation in REE is explained mainly by differences in the visceral component of LTM, with additional minor information from the total-body FTM, androstenedione, and T 3.