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Helen T. Douda, Konstantina V. Kosmidou, Ilias Smilios, Konstantinos A. Volaklis and Savvas P. Tokmakidis

This five-year follow-up nonrandomized controlled study evaluated community-based training and detraining on body composition and functional ability in older women. Forty-two volunteers (64.3 ± 5.1 years) were divided into four groups: aerobic training, strength training, combined aerobic and strength, and control. Body composition and physical fitness were measured at baseline, after nine months of training and after three months of detraining every year. After five years of training, body fat decreased, and fat free mass, strength, and chair test performance increased (p < .05) in all training groups. Training-induced favorable adaptations were reversed during detraining but, eventually, training groups presented better values than the control group even after detraining. Thus, nine months of annual training, during a five-year period, induced favorable adaptations on body composition, muscular strength, and functional ability in older women. Three months of detraining, however, changed the favorable adaptations and underlined the need for uninterrupted exercise throughout life.

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Beau Kjerulf Greer, Kathleen M. Edsall and Anna E. Greer

The purpose of the current study was to determine whether expected changes in body weight via a 3-day low-carbohydrate (LC) diet will disrupt the reliability of air displacement plethysmography measurements via BOD POD. Twenty-four subjects recorded their typical diets for 3 days before BOD POD and 7-site skinfold analyses. Subjects were matched for lean body mass and divided into low-CHO (LC) and control (CON) groups. The LC group was given instruction intended to prevent more than 50 grams/day of carbohydrate consumption for 3 consecutive days, and the CON group replicated their previously recorded diet. Body composition measurements were repeated after dietary intervention. Test–retest reliability measures were significant (p < .01) and high for body fat percentage in both the LC and the CON groups (rs = .993 and .965, respectively). Likewise, skinfold analysis for body fat percentage reliability was high in both groups (rs = .996 and .997, respectively). There were significant differences between 1st and 2nd BOD POD measurements for body mass (72.9 ± 13.3 vs. 72.1 ± 13.0 kg [M ± SD]) and body volume (69.0 ± 12.7–68.1 ± 12.2 L) in the LC group (p < .05). However, there were no differences (p > .05) in BOD POD–determined body fat percentage, lean body mass, or fat mass between the 1st and 2nd trial in either group. Body composition measures via BOD POD and 7-site skinfolds remain reliable after 3 days of an LC diet despite significant decreases in body mass.

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Bruce Wayne Bailey, Pamela Borup, Larry Tucker, James LeCheminant, Matthew Allen and Whitney Hebbert

Background:

The aim of this study was to investigate the relationship between steps per day and adiposity among college women.

Methods:

This study was cross-sectional and included women ages 18–25. Participants wore a pedometer for 7 consecutive days. Body composition was assessed using air-displacement plethysmography. Height, weight, and waist and hip circumferences were assessed.

Results:

The women took 10,119 ± 2836 steps per day. When divided into quartiles by steps, the top 2 quartiles of women in the study had significantly lower BMI, percent body fat, and waist and hip circumferences than the bottom quartile of women (P ≤ .05). Percent body fat was different between the bottom 2 quartiles and the top 2 quartiles (P ≤ .05). The odds of having a body fat of greater than 32% were reduced by 21.9% for every increase of 1,000 steps taken per day (P ≤ .05).

Conclusions:

Steps per day are related to body composition in young adult women, but this relationship weakens with progressively higher step counts. A reasonable recommendation for steps in young adult women that is associated with the lowest BMIs and body fat seems to be between 10,000–12,000 steps per day.

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Thomas B. Walker, Jessica Smith, Monica Herrera, Breck Lebegue, Andrea Pinchak and Joseph Fischer

The purpose of this study was to investigate the ability of whey-protein and leucine supplementation to enhance physical and cognitive performance and body composition. Thirty moderately fit participants completed a modified Air Force fitness test, a computer-based cognition test, and a dual-energy X-ray-absorptiometry scan for body composition before and after supplementing their daily diet for 8 wk with either 19.7 g of whey protein and 6.2 g leucine (WPL) or a calorie-equivalent placebo (P). Bench-press performance increased significantly from Week 1 to Week 8 in the WPL group, whereas the increase in the P group was not significant. Push-up performance increased significantly for WPL, and P showed a nonsignificant increase. Total mass, fat-free mass, and lean body mass all increased significantly in the WPL group but showed no change in the P group. No differences were observed within or between groups for crunches, chin-ups, 3-mile-run time, or cognition. The authors conclude that supplementing with whey protein and leucine may provide an advantage to people whose performance benefits from increased upper body strength and/or lean body mass.

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Lucy-Joy M. Wachira, Stella K. Muthuri, Mark S. Tremblay and Vincent O. Onywera

Background:

The report card presents available evidence on the physical activity (PA) and body weight status of Kenyan children and youth. It highlights areas where Kenya is succeeding and those in which more action is needed.

Methods:

Comprehensive review and analysis of available data on core indicators for Kenyan children and youth 5−17 years were conducted. The grading system used was based on a set of specific criteria and existing grading schemes from similar report cards in other countries.

Results:

Of the 10 core indicators discussed, body composition was favorable (grade B) while overall PA levels, organized sport participation, and active play were assigned grades of C. Active transportation and sedentary behaviors were also favorable (grade B). Family/peers, school, governmental and nongovernmental strategies were graded C.

Conclusions:

The majority of Kenyan children and youth have healthy body composition levels and acceptable sedentary time, but are not doing as well in attaining the World Health Organization (WHO) recommendation on PA. Although Kenya seems to be doing well in most indicators compared with some developed countries, there is a need for action to address existing trends toward unhealthy lifestyles. More robust and representative data for all indicators are required.

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Magnus Carlsson, Tomas Carlsson, Daniel Hammarström, Christer Malm and Michail Tonkonogi

Purpose:

To investigate the relationship between race performance and lean mass (LM) variables, as well as to examine sex differences in body composition in elite-standard cross-country skiers.

Methods:

Thirty-four elite cross-country skiers (18 men and 16 women) underwent a dual-emission X-ray-absorptiometry body-composition test to determine LM, fat mass, and bone mineral content. For both sexes, performance data were collected from a sprint prologue and a distance race.

Results:

The absolute expression of LM variables (whole-body [LMWB], upper body [LMUB], and lower body [LMLB]) was significantly correlated with finishing time in the sprint prologue independent of sex. Distance-race performance was significantly related to LMWB, LMUB, and LMLB in women; however, no correlation was found in men. Men had a significantly higher LM and lower fat mass, independent of expression (absolute or relative), for the whole body, arms, trunk, and legs, except for the absolute fat mass in the trunk.

Conclusions:

The absolute expressions of LMWB, LMUB, and LMLB were significant predictors of sprint-prologue performance in both sexes, as well as of distance-race performance in women only. Compared with women, male skiers have a higher LM in the body segments that are major contributors to propelling forces. These results suggest that muscle mass in the lower and upper body is equally important for race performance; thus, more focus of elite skiers’ training should be directed to increasing whole-body muscle mass to improve their competitive performance capability.

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Ezzedine Bouhlel, Myriam Denguezli, Monia Zaouali, Zouhair Tabka and Roy J. Shephard

Purpose:

To evaluate the effect of Ramadan fasting on parameters of insulin resistance in trained athletes at rest and after aerobic exercise.

Methods:

Nine male rugby players (age 19 ± 2 yr, height 1.78 ± 0.74 m) were tested 3 times: 1 week before observance of Ramadan (C), at the end of the first week (R1), and during the fourth week (R2). They performed a progressive cycle-ergometer test at each visit. Data collected at rest and at the end of aerobic exercise included simple anthropometry (body mass, body-mass index, body fat, fat-free mass), biochemical parameters (serum glucose, cholesterol, HDL cholesterol, triglycerides, creatinine, and serum proteins), and selected hormone concentrations (plasma insulin, leptin, and adiponectin).

Results:

Ramadan fasting was associated with a reduction of body mass and body fat (R2 vs. C, p < .01) without significant change in leptin or adiponectin levels.

Conclusion:

Lipolysis might have occurred because of increased plasma triglycerides and HDL cholesterol concentrations.

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Robert Gorinski and Wendy Stuhldreher

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Jennifer Gornall and Rudolph G. Villani

The primary aim was to investigate whether the reduction in resting metabolic rate (RMR) and fat free mass (FFM) associated with a short-term very low kilojoule diet (VLKD) is altered by concurrent resistance exercise. Twenty overweight, premenopausal women were pair matched on body surface area and randomly assigned to either diet only (3,400 kJ/day) or diet combined with resistance training. Before and after 4 weeks of treatment, RMR was assessed by indirect calorimetry; total body mass (TBM), FFM, and fat mass (FM) by dual energy x-ray absorptiometry; total body water (TBW) by bioelectrical impedance; and strength by a weight-lifting test. Both groups had significantly lower TBM, FFM, FM, TBW, absolute RMR, and RMR, with FFM as the covariate, in the posttests than the pretests with no significant differences between groups. It was concluded that 4 weeks of resistance training did not prevent or reduce the decline in FFM and RMR observed with a VLKD.

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Kenneth H. Pitetti, Daniel A. Yarmer and Bo Fernhall

The purpose of this study was to compare the aerobic fitness and body mass index (BMI) of children and adolescents (8-18 yr) with and without mild mental retardation (MR). Sample size of participants with MR but without Down syndrome was 169 males and 99 females. Sample size of participants without MR was 289 males and 317 females. Analysis was made by gender and age: children (8-10 yr); early adolescents (11-14 yr); and late adolescents (15-18 yr). The 20-m shuttle run test (20 MST) was used to assess field test performance and predicted aerobic fitness. For all age groups, females and males without MR ran significantly more laps and had a significantly higher predicted aerobic fitness (V̇O2peak: ml $$ kg-1 $$ min-1) than their peers with MR. Additionally, participants with MR tended to have higher BMI than their peers without MR. The results of this study indicate that children and adolescents with MR have lower exercise capacity, lower aerobic fitness, and higher BMIs than their peers without MR.