Search Results

You are looking at 101 - 110 of 897 items for :

  • "body composition" x
Clear All
Restricted access

Olivier Rey, Jean-Marc Vallier, Caroline Nicol, Charles-Symphorien Mercier and Christophe Maïano

Purpose:

This study examined the effects of a five-week intervention combining vigorous interval training (VIT) with diet among twenty-four obese adolescents. Fourteen girls and ten boys (aged 14–15) schooled in a pediatric rehabilitation center participated.

Methods:

The VIT intensity was targeted and remained above 80% of maximal heart rate (HR) and over six kilocalories per minute. Pre- and postintervention measures were body composition (BMI, weight, body fat percentage), physical self-perceptions (PSP), physical fitness (6-min walking distance and work) and its associated physiological responses (HRpeak and blood lactate concentration). A series of two-way analyses of variance or covariance controlling for weight loss were used to examine the changes.

Results:

Significant improvements were found in body composition, physical fitness and PSP (endurance, activity level, sport competence, global physical self-concept and appearance). In addition, boys presented higher levels of perceived strength and global physical self-concept than girls. Finally, there was a significant increase in perceived endurance, sport competence, and global physical self-concept in girls only.

Conclusion:

This five-week VIT program combined with diet represents an effective means for improving body composition, physical fitness, and PSP in obese adolescents, the effects on PSP being larger among girls.

Restricted access

Paula B. Costa, Scott R. Richmond, Charles R. Smith, Brad Currier, Richard A. Stecker, Brad T. Gieske, Kimi Kemp, Kyle E. Witherbee and Chad M. Kerksick

” physique. Subsequently, these activities and others may increase these athletes’ risk for eating disorders. 3 – 5 However, identifying an ideal body composition profile presents a significant challenge given the nature of the sport, styles of presentation, and format of competition. 5 The combination of

Restricted access

Farah A. Ramirez-Marrero, John Miles, Michael J. Joyner and Timothy B. Curry

Background:

This study aimed to 1) describe physical activity (PA) in 15 post gastric bypass surgery (GB), 16 obese (Ob), and 14 lean (L) participants (mean ± se: age = 37.1 ± 1.6, 30.8 ± 1.9, 32.7 ± 2.3 yrs.; BMI = 29.7 ± 1.2, 38.2 ± 0.8, 22.9 ± 0.5 kg/m2, respectively); and 2) test associations between PA, body composition, and cardiorespiratory fitness (VO2max).

Methods:

Participants completed a PA questionnaire after wearing accelerometers from 5–7 days. Body composition was determined with DEXA and CT scans, and VO2max with open circuit spirometry. ANOVA was used to detect differences between groups, and linear regressions to evaluate associations between PA (self-reported, accelerometer), body composition, and VO2max.

Results:

Self-reported moderate to vigorous PA (MVPA) in GB, Ob, and L participants was 497.7 ± 215.9, 988.6 ± 230.8, and 770.7 ± 249.3 min/week, respectively (P = .51); accelerometer MVPA was 185.9 ± 41.7, 132.3 ± 51.1, and 322.2 ± 51.1 min/week, respectively (P = .03); and steps/day were 6647 ± 141, 6603 ± 377, and 9591 ± 377, respectively (P = .03). Ob showed a marginally higher difference between self-report and accelerometer MVPA (P = .06). Accelerometer-MVPA and steps/day were inversely associated with percent fat (r = –0.53, –0.46), and abdominal fat (r = –0.36, –0.40), and directly associated with VO2max (r = .36).

Conclusions:

PA was similar between GB and Ob participants, and both were less active than L. Higher MVPA was associated with higher VO2max and lower body fat.

Restricted access

Scott C. Forbes, Nathan Sletten, Cody Durrer, Étienne Myette-Côté, D. Candow and Jonathan P. Little

High-intensity interval training (HIIT) has been shown to improve cardiorespiratory fitness, performance, body composition, and insulin sensitivity. Creatine (Cr) supplementation may augment responses to HIIT, leading to even greater physiological adaptations. The purpose of this study was to determine the effects of 4 weeks of HIIT (three sessions/week) combined with Cr supplementation in recreationally active females. Seventeen females (age = 23 ± 4 yrs; BMI = 23.4 ± 2.4) were randomly assigned to either Cr (Cr; 0.3 g・kg-1・d-1 for 5 d followed by 0.1 g・kg-1・d-1 for 23 days; n = 9) or placebo (PLA; n = 8). Before and after the intervention, VO2peak, ventilatory threshold (VT), time-trial performance, lean body mass and fat mass, and insulin sensitivity were assessed. HIIT improved VO2peak (Cr = +10.2%; PLA = +8.8%), VT (Cr = +12.7%; PLA = +9.9%), and time-trial performance (Cr = -11.5%; PLA = -11.6%) with no differences between groups (time main effects, all p < .001). There were no changes over time for fat mass (Cr = -0.3%; PLA = +4.3%), whole-body lean mass (Cr = +0.5%; PLA = -0.9%), or insulin resistance (Cr = +3.9%; PLA = +18.7%). In conclusion, HIIT is an effective way to improve cardiorespiratory fitness, VT, and time-trial performance. The addition of Cr to HIIT did not augment improvements in cardiorespiratory fitness, performance or body composition in recreationally active females.

Restricted access

Alex S. Ribeiro, Brad J. Schoenfeld, Danilo R.P. Silva, Fábio L.C. Pina, Débora A. Guariglia, Marcelo Porto, Nailza Maestá, Roberto C. Burini and Edilson S. Cyrino

The purpose of this study was to compare different split resistance training routines on body composition and muscular strength in elite bodybuilders. Ten male bodybuilders (26.7 ± 2.7 years, 85.3 ± 10.4 kg) were randomly assigned into one of two resistance training groups: 4 and 6 times per week (G4× and G6×, respectively), in which the individuals trained for 4 weeks, 4 sets for each exercise performing 6–12 repetitions maximum (RM) in a pyramid fashion. Body composition was assessed by dual energy X-ray absorptiometry, muscle strength was evaluated by 1RM bench-press testing. The food intake was planned by nutritionists and offered individually throughout the duration of the experiment. Significant increases (p < .05) in fat-free mass (G4× = +4.2%, G6× = +3.5%) and muscular strength (G4× = +8.4%, G6× = +11.4%) with no group by time interaction were observed. We conclude that 4 and 6 weekly sessions frequencies of resistance training promote similar increases in fat-free mass and muscular strength in elite bodybuilders.

Restricted access

Maxwell Ruby, Chris P. Repka and Paul J. Arciero

Background:

Yoga/Stretching (YS) and functional resistance (FR) training are popular exercise routines. A protein-pacing (PP) diet is a common dietary regimen. Thus, we assessed the effectiveness of a PP diet alone and in combination with either YS or FR to improve body composition and cardiometabolic health.

Methods:

Twenty-seven overweight women (age = 43.2 ± 4.6 years) were randomized into 3 groups: yoga (YS, n = 8) or resistance (FR, n = 10) training (3 days/week) in conjunction with PP diet (50% carbohydrate, 25% protein, and 25% fat) or PP diet-only (PP, n = 9) throughout 12-week study. PP maintained preexisting levels of physical activity. Body weight (BW), total (BF) and abdominal (ABF) body fat, waist circumference (WC), plasma biomarkers, and aerobic fitness (VO2) were measured at baseline and 12 weeks.

Results:

WC and total cholesterol improved in all groups, whereas glycemia tended to improve (P = .06) in S. BF, ABF, and VO2 increased significantly in YS and FR (P < .05). Feelings of vigor increased in YS and tension decreased in FR (P < .05).

Conclusions:

YS training tended to decrease blood glucose compared with FR and PP and is equally effective at enhancing body composition, and aerobic fitness in overweight women providing a strong rationale for further research on YS training.

Restricted access

Gary Slater, David Jenkins, Peter Logan, Hamilton Lee, Matthew Vukovich, John A. Rathmacher and Allan G. Hahn

This investigation evaluated the effects of oral β-Hydroxy-β-Methylbutyrate (HMB) supplementation on training responses in resistance-trained male athletes who were randomly administered HMB in standard encapsulation (SH), HMB in time release capsule (TRH), or placebo (P) in a double-blind fashion. Subjects ingested 3 g · day−1 of HMB or placebo for 6 weeks. Tests were conducted pre-supplementation and following 3 and 6 weeks of supplementation. The testing battery assessed body mass, body composition (using dual energy x-ray absorptiometry), and 3-repetition maximum isoinertial strength, plus biochemical parameters, including markers of muscle damage and muscle protein turnover. While the training and dietary intervention of the investigation resulted in significant strength gains (p < .001) and an increase in total lean mass (p = .01), HMB administration had no influence on these variables. Likewise, biochemical markers of muscle protein turnover and muscle damage were also unaffected by HMB supplementation. The data indicate that 6 weeks of HMB supplementation in either SH or TRH form does not influence changes in strength and body composition in response to resistance training in strength-trained athletes.

Restricted access

Sijie Tan, Cheng Chen, Mingyang Sui, Lunan Xue and Jianxiong Wang

Objectives:

To explore the effects of exercise training on body composition, cardiovascular function, and physical fitness in 5-year-old obese and lean children.

Methods:

42 obese and 62 lean children were randomly allocated into exercise and control groups separately. Body composition, cardiovascular function, and physical fitness were measured at baseline and the end of the intervention. The exercise groups participated in 10 weeks of supervised moderate intensity exercise training (at 50% of heart rate reserve), 50 training sessions in total.

Results:

The physical activity program was successfully completed and no sport injury occurred. Exercise training decreased BMI, waist circumference, body fat%, and fat mass; and slowed down the growth speed of body mass of both trained obese and lean children. Exercise training significantly decreased systolic blood pressure of obese children and decreased their heart rate responses during exercise. Trained obese children improved the performances of long jump, 10-m × 4 shuttle run, and 3-m balance beam walk; while trained lean children improved more items of physical fitness.

Conclusions:

10 weeks of moderate intensity exercise training is an effective and safe treatment for children aged 5 years, either obese or with normal body mass.

Restricted access

Kristel Võsoberg, Vallo Tillmann, Anna-Liisa Tamm, Toivo Jürimäe, Meeli Saar, Katre Maasalu, Inga Neissaar, Evelin Lätt and Jaak Jürimäe

The aim of this study was to describe longitudinal changes in body composition, leptin, adiponectin, and ghrelin over a 36-month period in prepubertal rhythmic gymnasts (RG) and their age-matched untrained controls (UC) entering into puberty. Thirty-five RG (8.0 ± 0.6 yrs) and 33 UC (8.2 ± 0.6 yrs) were followed at 12-month intervals for the next 3 years. Height, weight, pubertal stage, body composition, leptin, adiponectin, and ghrelin were measured at each time points. The pubertal development over the next 36 months was slower in the RG compared with UC. Leptin was increased in UC and remained unchanged in RG over 3-year study period (3.7 ± 3.6 vs. 0.2 ± 1.1 ng/ml; p < .05). In RG, baseline leptin was negatively correlated with the change in body fat percentage over a 36-month period (r = −0.34; p < .05). The change in adiponectin over the study period was negatively correlated with the change in BMI (r = −0.43; p < .05). RG had relative leptin deficiency per body fat mass. In conclusion, relatively high leptin concentration at the beginning of puberty may predict those girls who do not increase their body fat percentage through coming years and therefore may have increased risk for delayed puberty.

Restricted access

Antonio García-Hermoso, Mairena Sánchez-López and Vicente Martínez-Vizcaíno

The purpose of this meta-analysis of randomized trials was to determine the effectiveness of aerobic plus resistance exercise interventions on body composition related to variables in overweight and obese youth. A computerized search was made of 7 databases. The analysis was restricted to randomized controlled trials that examined the effect of aerobic and resistance exercise on body composition (body weight, body mass index, fat mass, fat-free mass, and waist circumference) in obese youth. Two independent reviewers screened studies and extracted data. Weighted mean differences (WMD) and 95% confidence intervals were calculated. Nine studies were selected for meta-analysis as they fulfilled the inclusion criteria (n = 365). Aerobic plus resistance exercise interventions (8–24 weeks duration) produced a decrease in body weight (WMD=-3.31 kg), body mass index (WMD=-1.05 kg/m2), and fat mass (WMD=-1.93% and 5.05 kg), but changes in fatfree mass and waist circumference were not observed. These changes were accentuated through programs of at least 60 min of exercise per session, generating greater reductions in body weight (WMD=-4.11 kg), fat mass (WMD=-4.07%), and increase in fat-free mass (WMD = 2.45 kg). This meta-analysis provides insight into the effectiveness of short-term aerobic plus resistance exercise interventions for decreasing body weight, body mass index, and fat mass in pediatric obesity.