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The purpose of this study was to investigate the effects of supplementation of whey protein (WP) versus leucine-matched collagen peptides (CP) on muscle thickness MT and performance after a resistance training (RT) program in young adults. Twenty-two healthy untrained participants were randomly assigned to either a WP (n = 11) or leucine-matched CP (n = 11) group and then submitted to a supervised 10-week RT program (3 days/week). The groups were supplemented with an equivalent amount of WP (35 g, containing 3.0 g of leucine) and CP (35 g, containing 1.0 g of leucine and 2.0 g of free leucine) during the intervention period (after each workout and in the evening on nontraining days). MT of the vastus lateralis and biceps brachii, isokinetic peak torque and mean power output of the elbow flexors, and peak power output of the lower body were assessed before and after the RT program. The WP group experienced a greater (interaction, p <.05) increase in the vastus lateralis (effect size, WP = 0.68 vs. CP = 0.38; % Δ, WP = 8.4 ± 2.5 vs. CP = 5.6 ± 2.6%) and biceps brachii muscle thickness (effect size, WP = 0.61 vs. CP = 0.35; % , WP = 10.1 ± 3.8 vs. CP = 6.0 ± 3.2%), with a similar increase in muscle performance (peak torque, mean power output, and peak power output) between groups (time p <.05). Supplementation with WP was superior to leucine content-matched CP supplementation in increasing muscle size, but not strength and power, after a 10-week RT program in young adults. [ABSTRACT FROM AUTHOR]

This study aimed to compare the effects of resistance training performed with low versus moderate loads on systemic resting blood pressure (BP) in older women. A total of 29 women (72.6 ± 5.1 years) were randomized into two groups: low load (LOW, n = 15) and moderate load (MOD, n = 14). An 8-week whole-body resistance training program was carried out 3 days/week (eight exercises, three sets, 10 or 15 repetition maximum). The LOW and MOD groups trained with a relative load of 15 and 10 repetition maximum, respectively. Outcome measures included resting systolic and diastolic BP. After 8 weeks, both groups presented significant changes (p <.05) in systolic BP (LOW = −3.0%; MOD = −4.6%) and mean BP (LOW = −1.9%; MOD = −3.1%). There was no change for diastolic BP in the posttest in both groups. The results suggest that low and moderate loads are equally effective for promoting decreases in resting BP in older women. [ABSTRACT FROM AUTHOR]

The authors aimed to compare the effects of creatine (Cr) supplementation combined with resistance training on skeletal muscle mass (SMM), total body water, intracellular water (ICW), and extracellular water (ECW) in resistance-trained men as well as to determine whether the SMM/ICW ratio changes in response to the use of this ergogenic aid. Twenty-seven resistance-trained men received either Cr (n = 14) or placebo (n = 13) over 8 weeks. During the same period, subjects performed two split resistance training routines four times per week. SMM was estimated from appendicular lean soft tissue assessed by dual-energy X-ray absorptiometry. Total body water, ICW, and ECW were determined by spectral bioelectrical impedance. Both groups showed improvements (p <.05) in SMM, total body water, and ICW, with greater values observed for the Cr group compared with placebo. ECW increased similarly in both groups (p <.05). The SMM/ICW ratio did not change in either group (p >.05), whereas the SMM/ECW ratio decreased only in the Cr group (p <.05). A positive correlation was observed (p <.05) between SMM and ICW changes (r =.71). The authors' results suggest that the increase in muscle mass induced by Cr combined with resistance training occurs without alteration of the ratio of ICW to SMM in resistance-trained men. [ABSTRACT FROM AUTHOR]

Background: This investigation aimed to analyze the agreement between the GT3X accelerometer and the ActivPAL inclinometer for estimating and detecting changes in sedentary behavior of different contexts among adolescents. Methods: Secondary data from an intervention using standing desks in the classroom conducted within 2 sixth-grade classes (intervention [n = 22] and control [n = 27]) were used. The intervention took place over 16 weeks, with activity assessments (ActivPAL and GT3X) being performed 7 days before and in the last week of the intervention. Baseline information from both groups was considered for cross-sectional analysis (209 valid days), while data from 20 participants (intervention group) were used for longitudinal analysis. Results: The authors observed that GT3X overestimated sedentary time at school (16.8%), after school (13.5%), and during weekends (7.3%) compared with ActivPAL (P < .05). Outside the school (after school [r = -.188] and on weekends [r = -.260]), there was a trend to higher overestimation among adolescents with less sedentary behavior. Longitudinally, the GT3X was unable to detect changes resulting froman intervention in school hours (ActivPAL = -34.7 min·9 h-1 vs GT3X= +6.7 min·9 h-1; P < .05). Conclusions: The authors conclude that GT3X (cut-point of <100 counts·min-1) overestimated sedentary time of free-living activities and did not detect changes resulting from a classroom standing desk intervention in adolescents. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of protein intake beyond habitual intakes associated with resistance training on metabolic syndrome (MetS)-related parameters, isokinetic strength, and body composition in health older women. A total of 30 older women (68.8 ± 4.3 years) participated in this investigation and were assigned to receive 35 g of whey protein or placebo combined with resistance training, over 12-weeks, three times per week. Blood samples, blood pressure, dietary intake, strength, and body composition were assessed before and after the intervention period. Two-way analysis of variance for repeated measures was applied for comparisons. Both groups improved the skeletal muscle mass, muscular strength, waist circumference, triglycerides, high-density lipoprotein, glucose, resistance, reactance, and MetS Z-score risk. However, the improvements in skeletal muscle mass, waist circumference, and MetS Z-score risk were significantly greater in protein group when compared with control group. Moreover, protein group significantly decreased %body fat when compared with control group. Higher protein intake combined with resistance training promoted greater improvements in skeletal muscle mass, %body fat, waist circumference, and MetS Z-score risk in older women. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyze the association between muscle quality index (MQI) and phase angle (PhA) after a program of progressive resistance training (RT) in older women. Sixty-six older women with previous RT experience (68.8 ± 4.6 years, 156.6 ±5.3 cm, 66.0 ± 13.0 kg, and 26.7 ± 4.6 kg/m²) underwent 12 weeks of RT (3 x/week, eight exercises, and 10-15 repetition maximum). Anthropometry, muscular strength (one-repetition maximum tests), and body composition (dual-energy X-ray absorptiometry and spectral bioimpedance) were measured pre- and posttraining. There were observed significant increases for PhA, MQI, muscular strength, muscle mass, and reactance, whereas no significant changes in body fat and resistance were found. A significant correlation was observed between the RT-induced relative changes in PhA and MQI (r = .620). We conclude that improvements in MQI induced by RT are associated with increases in PhA. Therefore, PhA may be a valid tool to track changes in MQI after 12 weeks of RT in older women. [ABSTRACT FROM AUTHOR]

The purpose of the study was to clarify the independent association between sedentary behavior and physical activity with multiple chronic diseases and medicine intake in older individuals. Sedentary behavior and physical activity were measured by questionnaires. Diseases and medication use were self-reported. Poisson's regression was adopted for main analysis, through crude and adjusted prevalence ratio and confidence interval of 95%. For men, sedentary time >4 hr/day presented a 76% higher prevalence of ≥2 chronic diseases, while physical inactivity increases the likelihood of using ≥2 medicines in 95%. For women, sedentary behavior >4 hr/day presented an 82% and 43% greater prevalence for ≥2 chronic diseases and the intake of ≥2 medicines, respectively. Sedentary behavior represents an independent associated factor of multiple chronic diseases in older men and women. In addition, inactivity for men and sedentarism for women are associated with the amount of medicine intake. [ABSTRACT FROM AUTHOR]

The main purpose of this study was to compare the effects of resistance training (RT) performed two versus three times per week on phase angle (a cellular health indicator) in older women. A total of 39 women (69.1 ± 5.5 years) were randomly assigned to perform a RT program two (G2X) or three (G3X) days per week for 12 weeks. The RT was a whole-body program (eight exercises, one set, 10–15 repetitions). Phase angle, resistance, reactance, and total body water were assessed by bioimpedance spectroscopy. Intracellular water, reactance, and phase angle increased significantly in G2X (2.1%, 3.0%, and 5.6%, respectively) and G3X (5.0%, 6.9%, and 10.3%, respectively) from pretraining to posttraining, with no significant difference between groups. Bioimpedance resistance decreased similarly in both groups (G2X = −1.7% vs. G3X = −3.2%). We conclude that a single set RT program with a frequency of 2 days per week may be sufficient to promote an improvement in cellular health in older women. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of whey protein (WP) supplementation on muscular strength, hypertrophy, and muscular quality in older women preconditioned to resistance training (RT). In a randomized, double-blind, and placebo (PLA)-controlled design, 31 older women (67.4 ± 4.0 years, 62.0 ± 6.9 kg, 155.9 ± 5.7 cm, and 25.5 ± 2.4 kg/m2) received either 35 g of WP (n = 15) or 35 g of PLA (n = 16) over a 12-week study period while performing an RT program three times a week. Dietary intake, one-repetition maximum test, and skeletal muscle mass by dual-energy X-ray absorptiometry were assessed before and after the intervention period. Both groups showed significant (p <.05) improvements in skeletal muscle mass and total strength, and the WP group realized greater increases (p <.05) in these measures compared with PLA (skeletal muscle mass: WP = +4.8% vs. PLA = +2.3%; strength: WP = +8.7% vs. PLA = +4.9%). Muscular quality increased (p <.05) in both groups (WP = +2.9% vs. PLA = +1.5%) without statistical differences (p >.05) noted between conditions. We conclude that WP supplementation in combination with RT induces higher increases in both strength and hypertrophy in older women preconditioned to RT. [ABSTRACT FROM AUTHOR]

Background: This study describes the levels and patterns of television (TV) viewing in Brazilian adults and investigates associations of TV viewing with hypertension, type 2 diabetes, and heart disease. Methods: Data from the Brazilian Health Survey, a nationally representative survey that was conducted in 2013 (N = 60,202 men and women age≥ =18 y), were used. Information regarding TV viewing, physician diagnoses of type 2 diabetes, hypertension, and heart disease was collected via interview-administered questionnaire. Data on covariables (including chronological age, educational status, skin color, sodium consumption, sugar consumption, tobacco smoking, alcohol consumption, and leisure-time physical activity) were also selfreported. Logistic regression models and population attributable fractions were used for the etiological analyses. Results: The prevalence (95% confidence interval) of >4 hours per day of TV viewing was 12.7% (12.0-13.4) in men and 17.5% (16.8-18.3) in women. Men and women being younger or older, moderately educated, living alone, smoking tobacco, and drinking alcohol were associated with higher reported TV viewing time. Odds ratios (95% confidence interval) revealed that >4 hours per day of TV viewing was associated with type 2 diabetes [male: 1.64 (1.23-2.17) and female: 1.33 (1.09-1.63)], hypertension [male: 1.36 (1.14-1.63) and female: 1.20 (1.05-1.37)], and heart disease [male: 1.96 (1.43-2.69) and female: 1.30 (1.00-1.68)]. Exceeding 4 hours per day of TV viewing was responsible for 6.8% of type 2 diabetes, 3.7% of hypertension, and 7.5% of heart disease cases. Conclusions: Independent of covariates, >4 hours per day of TV viewing was associated with type 2 diabetes, hypertension, and heart disease. High volumes of TV viewing are prevalent and appear to contribute to chronic disease burden. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of two different resistance training (RT) systems on oxidative stress biomarkers in older women. Fifty-nine older women (67.9 ± 5.0 years) were randomly assigned to one of three groups. Two training groups performed an 8 week RT program either in traditional (TD, n = 20) or a pyramid (PR, n = 20) system 3 times per week, or a control group (CG, n = 19). The TD program consisted of 3 sets of 8-12 RM with constant load for the 3 sets, whereas the PR training consisted of 3 sets of 12/10/8 RM with incremental loads for each set. As compared with the CG, both TD and PR achieved upregulation of the antioxidant system as evidenced by higher (p < .05) values of total radical-trapping antioxidant parameter plasma concentration after intervention (TD= 930.4 ± 160.0 µmolTrolox, PR= 977.8 ± 145.2 µmolTrolox, CG= 794.4 ± 130.2 µmolTrolox). For the protein oxidation adducts, TD and PR presented lower (p < .05) scores compared with CG (TD= 91.2 ± 25.0 µmol/L, PR= 93.0 ± 30.3 µmol/L, CG= 111.0 ± 20.4 µmol/L). However, there were no differences (p > .05) between trained groups in the antioxidant capacity markers and in the protein oxidation adducts markers. The results suggest that 8 weeks of progressive RT promotes an improvement in markers of oxidative stress in older women independent of the load-management RT system. [ABSTRACT FROM AUTHOR]

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 (G4x and G6x, 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 (G4x = +4.2%, G6x = +3.5%) and muscular strength (G4x = +8.4%, G6x = +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. [ABSTRACT FROM AUTHOR]