Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “BODY”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 685 records · Page 38Linked to original sources

Effect of body build on weight-training-induced adaptations in body composition and muscular strength.

The aim of the present study was to investigate whether weight-training-induced adaptations in body composition and isokinetic strength differ as a function of body build. Body build of a subject was characterized as the extent to which a person's fat-free mass index (FFMI = fat-free mass.height-2;kg.m-2) differs from the regression of FFMI over fat mass index (FMI = fat mass.height-2;kg.m-2) as derived from a sedentary male population (N = 77). From this population two groups with either a slender (N = 10) or a solid (N = 11) body build were selected. For 12 wk the subjects performed a weight-training program twice a week. Training induced a significant (P < 0.05) increase in fat-free mass (FFM) in the solid group (1.6 kg, 2.3%) in contrast with the slender group, which showed no significant change in FFM. Both groups showed comparable decreases in fat mass (FM; slender: -1.7 kg, -10.8% versus solid: -2.4 kg, -11.3%) and increases in strength (on average 13.8%). In conclusion, the increase in FFM due to a weight-training program is modified by body build. This modification, however, is restricted to a larger increase in the solidly built group.

Adaptation, Physiological↗

Whole body BMC in pediatric Crohn disease: independent effects of altered growth, maturation, and body composition.

UNLABELLED: Whole body BMC was assessed in 104 children and young adults with CD and 233 healthy controls. CD was associated with significant deficits in BMC and lean mass, relative to height. Adjustment for lean mass eliminated the bone deficit in CD. Steroid exposure was associated with short stature but not bone deficits relative to height. INTRODUCTION: Children with Crohn disease (CD) have multiple risk factors for impaired bone accrual. The confounding effects of poor growth and delayed maturation limit the interpretation of prior studies of bone health in CD. The objective of this study was to assess BMC relative to growth, body composition, and maturation in CD compared with controls. MATERIALS AND METHODS: Whole body BMC and lean mass were assessed by DXA in 104 CD subjects and 233 healthy controls, 4-26 years of age. Multivariable linear regression models were developed to sequentially adjust for differences in skeletal size, pubertal maturation, and muscle mass. BMC-for-height z scores were derived to determine CD-specific covariates associated with bone deficits. RESULTS: Subjects with CD had significantly lower height z score, body mass index z score, and lean mass relative to height compared with controls (all p < 0.0001). After adjustment for group differences in age, height, and race, the ratio of BMC in CD relative to controls was significantly reduced in males (0.86; 95% CI, 0.83, 0.94) and females (0.91; 95% CI, 0.85, 0.98) with CD. Adjustment for pubertal maturation did not alter the estimate; however, addition of lean mass to the model eliminated the bone deficit. Steroid exposure was associated with short stature but not bone deficits. CONCLUSION: This study shows the importance of considering differences in body size and composition when interpreting DXA data in children with chronic inflammatory conditions and shows an association between deficits in muscle mass and bone in pediatric CD.

Absorptiometry, Photon↗

Do changes in body mass index percentile reflect changes in body composition in children? Data from the Fels Longitudinal Study.

OBJECTIVE: Our aim was to examine the degree to which changes in BMI percentile reflect changes in body fat and lean body mass during childhood and how age and gender affect these relationships. METHODS: This analysis used serial data on 494 white boys and girls who were aged 8 to 18 years and participating in the Fels Longitudinal Study (total 2319 observations). Total body fat (TBF), total body fat-free mass (FFM), and percentage of body fat (%BF) were determined by hydrodensitometry, and then BMI was partitioned into its fat and fat-free components: fat mass index (FMI) and FFM index (FFMI). We calculated predicted changes (Delta) in FMI, FFMI, and %BF for each 10-unit increase in BMI percentile using mixed-effects models. RESULTS: FFMI had a linear relationship with BMI percentile, whereas FMI and %BF tended to increase dramatically only at higher BMI percentiles. Gender and age had significant effects on the relationship between BMI percentile and FFMI, FMI, and %BF. Predicted Delta%BF for boys 13 to 18 years of age was negative, suggesting loss of relative fatness for each 10-unit increase in BMI percentile. CONCLUSIONS: In this longitudinal study of white children, FFMI consistently increased with BMI percentile, whereas FMI and %BF had more complicated relationships with BMI percentile depending on gender, age, and whether BMI percentile was high or low. Our results suggest that BMI percentile changes may not accurately reflect changes in adiposity in children over time, particularly among male adolescents and children of lower BMI.

Adolescent↗

Body-size judgments and eye movements associated with looking at body regions in obese and normal weight subjects.

Eye movements of 20 male and 20 female obese and nonobese subjects were monitored during two body-size estimation tasks using a computer-based video technology. Analysis indicated no differences in body-size estimation between subjects using the staircase method. All subjects slightly underestimated body size; however, obese subjects were more sensitive than normal-weight subjects in detecting size distortion when a signal-detection task was employed. Eye-movement data indicated subjects looked longest at the chest, followed by waist, head, thighs, and calves/feet, in both the staircase and the signal-detection methods. Women viewed the waist region longer than men. On a signal-detection task subjects were better at detecting body-size distortion when viewing the body from the back than from front or profile.

Adolescent↗

Relationship between body image and percent body fat among college male varsity athletes and nonathletes.

Three groups of students from a large midwestern university (15 varsity swimmers, 15 varsity football players, and 15 nonathletes) were administered a 20-item questionnaire concerned with body image and subsequently underwent skinfold measurements to assess percent body fat. Scores obtained were correlated to estimate the relationship between body image and adiposity. For the groups combined (N = 45) the relationship was significant and inverse (r = -0.51). For the nonathletic group a significant value -0.76 was found; for the two groups of athletes there was no relationship (rs = 0.002 and -0.059 for football players and swimmers, respectively). We conclude that body image as measured in this study in inversely related to percent body fat among college men, especially among students not engaged in varsity sports.

Adipose Tissue↗

Body composition evaluation in peritoneal dialysis patients using anthropometric formulas estimating body water.

In adult patients on peritoneal dialysis (PD), estimates of body water (V), fat-free mass (FFM), and body fat (BF) can be obtained by using anthropometric formulas for estimating V. Estimates of V, FFM, and BF can also be obtained by using reference (standard) methods in which V is evaluated by a standard dilution method. To test whether the estimates obtained by the various methods agree, we analyzed published studies that measured V by a standard method in adult PD patients. We then calculated V, FFM, and BF by the Watson, Hume, Sahlgrenska, Chumlea, Lee, and Chertow formulas for the "average subject" in the published studies. We compared the standard and the anthropometric estimates using the limits-of-agreement method of Bland and Altman. Our analysis included six studies involving a total of 262 patients (89 women, 173 men). The six studies measured V by a reference method and allowed calculation of anthropometric V, FFM, and BF for the average patient. We calculated these values: VStandard, 36.8 +/- 4.7 L; VSahlgrenska, 36.9 +/- 4.3 L [p = nonsignificant (NS); Bland-Altman limits of agreement: -3.1 L to 3.3 L]; FFMStandard 50.9 +/- 5.2 kg; FFMSahlgrenska, 50.6 +/- 4.3 kg (Bland-Altman limits of agreement: -5.4 kg to 4.8 kg); BFStandard, 20.3 +/- 3.0 kg; BFSahlgrenska, 20.6 +/- 2.3 kg (Bland-Altman limits of agreement: -4.8 kg to 5.4 kg). Results obtained using the Watson, Hume, Chumlea, and Lee formulas also agreed with the standard estimates. The Chertow formula produced results that systematically overestimated the standard V and FFM values and that underestimated the standard BF. The Watson, Hume, Sahlgrenska, Chumlea, and Lee anthropometric formulas used to calculate V provide estimates of body composition that approximate those obtained using standard methods in PD patients with average body composition. Anthropometric estimates may cause large systematic errors in PD patients whose body composition varies from the average, particularly obese or overhydrated patients.

Anthropometry↗

Tetrapolar body impedance is influenced by body posture and plasma sodium concentration.

Tetrapolar body impedance measures body resistance, which is highly correlated to total body water and fat-free mass. We investigated the change in resistance measured with tetrapolar impedance, resulting from fluid shifts, following an altered body posture and changes in resistance following an altered electrolyte composition of the extracellular fluid during hypertonic saline and mannitol infusion. An increase in body resistance was measured during recumbency, which was positively correlated with the calculated shift of interstitial fluid to the intravascular space. This effect was completely abolished after 5 min in the upright position. During infusion of 5% saline or 20% mannitol the change in resistance and the change in plasma sodium concentration were inversely correlated. Therefore the measurement of resistance is essentially influenced by alterations in the amount and composition of extracellular fluids. Using the resistance measurements standardization is obligatory for posture and plasma sodium concentration. This is particularly important when repeated measurements are performed.

Adult↗

Effect of body size and body composition on survival in peritoneal dialysis patients.

BACKGROUND: Using 24-hour urinary creatinine excretion as a measure of muscle mass, we examined whether body composition influences the survival of incident peritoneal dialysis (PD) patients. We hypothesized that patients with high body mass index (BMI) and low muscle mass might be considered to have high levels of body fat. METHODS: Using serum creatinines and creatinine clearances reported on Medical Evidence Form 2728, 24-hour urinary creatinine was calculated in 10 140 incident PD patients with normal (18.5 - 24.9 kg/m2) or high (> or = 25 kg/m2) BMI. Patients were classified as low and normal/high muscle mass groups based on the 25th percentile of 24-hour urinary creatinine (0.64 g/day). RESULTS: In multivariable parametric survival models, compared to the normal BMI-normal/high muscle mass patients, high BMI-normal/high muscle mass patients had lower hazard of all-cause [hazard ratio (HR) 0.90, 95% confidence interval (CI) 0.83 - 0.97] and cardiovascular (HR 0.88, 95% CI 0.79 - 0.97) death; high BMI patients with low muscle mass had higher hazard of all-cause (HR 1.29, 95% CI 1.17 - 1.42) and cardiovascular (HR 1.21, 95% CI 1.06 - 1.39) death. CONCLUSION: Both body size and body composition influence survival of incident PD patients. As incident PD patients with high BMI and normal or high muscle mass have the best survival, PD patients should be encouraged to gain muscle mass rather than fat mass.

Adult↗

Determining the rate of body heat storage by incorporating body composition.

The rate of body heat storage (S) is often used as an index of thermal stress. The traditional approach for determining S assumes that the specific heat (Cp) of all body tissues may be averaged to 0.83 kcal X kg-1 X degrees C-1, irrespective of the actual proportion of different tissues in the body. The present theoretical analysis primarily partitions the body into N compartments. However, this analytical approach involves the difficulty of making an exact evaluation of the mass and temperature of multiple compartments. Therefore, by adopting a two-compartment (core and shell) model, the specific heat capacities, mass fractions, and changes in the temperatures of the two compartments are combined, and S is defined as a function of adiposity (= mass fraction of peripheral tissues). Evaluation of a newly developed equation showed close agreement with observations during a series of cold-water immersion trials, and indicated that the new approach seems to adequately predict S as related to body composition.

Adult↗

[Spirometric studies in clinically healthy workers in steel mills. I. Effect of age, body height and body weight on the variability of selected ventilation indicators].

Of 2750 examined workers of the Lenin steel mill a group of 520 so called healthy men aged 20-60 has been selected, who had developed chronic specific and inspecific diseases of the respiratory tract, and circulatory diseases during myocardial insufficiency and arterial hypertension. This population underwent tests performed by the F function, test of significance of differences between coefficients of multiple determination in the function of age, growth and body weight, and in the function of: age and height; age and body weight, height and body weight, which allowed to determine the contribution of age, height and body weight in the significance of the following spirometric indices: VC, FEV1%VC, RV, ERV, FRC, RV% TLC, TLC. Age exhibited statistically significant contribution to the total variance of VC, FEV1%VC, RV, ERV, FRC RV%TLC, and insignificant--in case of TLC. Height exhibits significant impace on VC, RV, ERV, FRC, TLC, RV%TLC. Statistically insignificant dependence on height was obtained in case of FEV1%VC. Inclusion of body weight showed a statistically significant explanatory value for VC, RC, ERV, FRC RV%TLC, and insignificant for TLC and FEV1%VC.

Adult↗

Influences of body weight, body composition, and substrate oxidation rate on resting postabsorptive glucose production and gluconeogenesis.

OBJECTIVE: To determine the influence of body weight, fat mass, and fat distribution on resting endogenous glucose production in healthy lean and overweight individuals. DESIGN: measurements were performed in the resting postabsorptive state in individuals receiving an unrestricted diet. SETTING: Institute of Physiology of Lausanne University. MEASUREMENTS: resting post absorptive glucose production, glycogenolysis and gluconeogenesis; resting energy expenditure and net substrate oxidation. RESULTS: Endogenous glucose production was positively correlated with body weight, lean body mass, energy expenditure and carbohydrate oxidation. Gluconeogenesis was positively correlated with net lipid oxidation and energy expenditure, and negatively correlated with net carbohydrate oxidation. No correlation with body fat or fat distribution was observed. CONCLUSIONS: Gluconeogenesis shows a large interindividual variability. Net lipid oxidation and not body fat appears to be a major determinant of gluconeogenesis.

Adult↗

Precision and accuracy of total body bone mass and body composition measurements in the rat using x-ray-based dual photon absorptiometry.

Lean body mass (LBM), total body bone mineral mass (BMC), total body bone areal density (BMD), and body fat mass (FM) were measured in rats by dual photon absorptiometry (DXA), using two different instruments. The coefficients of variation for repeated measurements of LBM and FM were about 0.4 and 2.5%, respectively, over an animal body weight range of 150 to 600 g. For BMC and BMD, the coefficients of variation were less than 2%. The correlation coefficients for LBM, FM, BMC, and BMD measured on the two densitometers were all greater than 0.94. The slope of the regression line relating LBM measured by DXA and LBM measured by carcass analysis was 0.999, and the correlation coefficient was 0.99. For FM the slope was 1.05, and the correlation coefficient was 0.98. BMC measures by DXA were falsely low in small animals. For larger animals, the correlation between BMC and ash weight was 0.93, but the slope of the regression line was 0.78. DXA measures of LBM and FM were accurate and reproducible for rats weighing between 150 and 600 g. There was a size-dependent error in BMC, which will be significant in longitudinal measurements of bone mass.

Absorptiometry, Photon↗

Effects of long-term calcium intake on body weight, body fat and bone in growing rats.

Increased calcium intake may reduce body weight and fat in non-growing individuals. This study explored the long-term effects of high versus low calcium intake on body weight, body fat, BMC, BMD and bone size in growing male and female rats. Ninety male and 90 female Sprague-Dawley rats were randomly assigned either to a high calcium (1%) or low calcium (0.25%) diet from age 3 weeks until 40 weeks. Half of the animals were fed ad libitum, and half of the animals were on an adjusted feeding schedule (the food intake of the low calcium animals was reduced to maintain equal body weight with high calcium animals of the same gender). DXA and radiographic measurements (femur and skull length and width) were collected at the age of 4, 13 and 34 weeks. Growing male rats fed the low calcium diet ad libitum gained more weight and more fat than rats on a high calcium diet. When food intake was controlled, male rats on the low calcium diet still had a greater fat mass (despite their similar body weight) and smaller skeletal measurements than the high calcium animals. Growing female rats initially responded like the males: when fed ad libitum low calcium animals had an increased body weight and fat mass; when food intake was controlled the low calcium animals had a greater fat mass and smaller skeletal measurements. However, these differences were found at 13 weeks and not at 34 weeks, suggesting a transient effect with no long-term differences between high and low calcium intake in the growing female rats.

Absorptiometry, Photon↗

Quantitative study of the comma-shaped body, S-shaped body and vascularized glomerulus in the second and third human gestational trimesters.

BACKGROUND: The rat developing metanephros has been quantified, but not the human developing kidney. AIMS: To contribute to the knowledge of the human developing kidney by studying the relative growth of the glomerular structures subtypes in the last two gestational trimesters. MATERIAL AND METHODS: The glomerular compartment of 21 human fetal left kidneys was studied. A stereological study determined the volume density (V(V)), the surface density (S(V)), and the numerical density in the plane (N(A)) of the developing glomeruli in the stages of comma-shaped body (C), S-shaped body (S), and vascularized glomerulus. Growth curves used log-transformed data and the allometric model. RESULTS: Reduction of both C and S bodies, and, consequently, a relative growth of the vascularized glomerulus from the second to the third trimesters. The differences between ages were not significant to the S body V(V) and S(V), but there was a significant N(A) reduction from the second to the third trimesters. An age-related reduction of the C body and an intense growth of the vascularized glomerulus were observed in this period. The allometric coefficient b was negative in both C and S bodies and positive in the vascularized glomerulus in the last two gestational trimesters. CONCLUSION: The growth equations and the observed tendencies of these glomerular subtypes in human fetal life could be useful to assess the kidney maturity through invasive or noninvasive investigative methods in the future.

Embryonic and Fetal Development↗

Spatial representation in body coordinates: evidence from errors in remembering positions of visual and auditory targets after active eye, head, and body movements.

Eight participants were presented with auditory or visual targets and then indicated the target's remembered positions relative to their head eight seconds after actively moving their eyes, head or body to pull apart head, retinal, body, and external space reference frames. Remembered target position was indicated by repositioning sounds or lights. Localization errors were found related to head-on-body position but not of eye-in-head or body-in-space for both auditory (0.023 dB/deg in the direction of head displacement) and visual targets (0.068 deg/deg in the direction opposite to head displacement). The results indicate that both auditory and visual localization use head-on-body information, suggesting a common coding into body coordinates--the only conversion that requires this information.

Acoustic Stimulation↗

Two-body and three-body wear of glass ionomer cements.

OBJECTIVES: Glass ionomer cements (GIC) have been modified in an attempt to improve their mechanical properties. The objective of the present paper was to compare the two-body and three-body wear of four modified GIC. The tested materials were Fuji IX (GC Corporation), Hi-Fi (Shofu) and Ketac Molar Aplicap (3M/ESPE). The cermet cement Ketac Silver Maxicap (3M/ESPE) was used as reference material. METHODS: Two-body wear tests were carried out in the computer controlled 'artificial mouth' of the Munich Dental School, three-body wear was tested with the ACTA wear machine. RESULTS: The resulting average two-body wear rates (in microm) were: Fuji IX 327 (SD +/- 82) < Ketac Molar 379 (SD +/- 94) < Hi-Fi 376 (SD +/- 90) < Ketac silver 449 (SD +/- 127). The differences between the materials were significant (P < 0.05, ANOVA, modified LSD-test) with the exception of Ketac Molar and Hi-Fi. The average three-body wear rates (in microm) were: Hi-Fi 30 (SD +/- 10) < Ketac Molar +/- 42 (SD +/- 12) < Fuji IX 49 (SD +/- 14) < Ketac silver 73 (SD +/- 23). The difference between Ketac silver and the three other materials was significant (P < 0.05, ANOVA, modified LSD-test). No significant difference was calculated between Hi-Fi, Ketac Molar and Fuji IX. CONCLUSIONS: As Ketac Molar, Hi-Fi and Fuji IX show better wear resistance compared to Ketac silver both in occlusal-contact and contact-free areas, it may be assumed that the wear resistance of a glass ionomer cement may be improved more by changing the powder: liquid ratio than by incorporating silver particles into the glass powder.

Analysis of Variance↗