Search

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]

Amarante do Nascimento, M, Nunes, JPA, Pina, FLC, Ribeiro, AS, Carneiro, NH, Venturini, D, Barbosa, DS, Mayhew, JL, and Cyrino, ES. Comparison of 2 weekly frequencies of resistance training on muscular strength, body composition, and metabolic biomarkers in resistance-trained older women: Effects of detraining and retraining. J Strength Cond Res 36(5): 1437–1444, 2022—This study aimed to compare the effects of 2 weekly frequencies of resistance training (RT) on muscular strength, body composition, and metabolic biomarkers in previously resistance-trained older women after detraining and retraining. Forty subjects (>60 years) performed RT (8 exercises, 1 set of 10–15 repetitions maximum) 2 (G2x) or 3 (G3x) times per week over 12 weeks of training and retraining. After training, subjects were detrained for 12 weeks. After detraining, there were significant decreases (p < 0.05) in upper-body (∼12%) and lower-body (∼14%) muscular strength, fat-free mass (FFM) (∼2%), and testosterone (∼26%), whereas increases were revealed for fat mass (FM) (∼4%), relative body fat (∼3%), fasting glucose (∼8%), low-density lipoprotein cholesterol (LDL-C) (∼21%), and triglycerides (∼24%), with no differences between groups (p > 0.05). Following retraining, there were significant increases (p < 0.05) for upper (∼7%) and lower (∼10%) muscular strength, FFM (∼2%), and testosterone (∼20%). In contrast, decreases were found for FM (∼7%), relative body fat (∼3%), fasting glucose (∼6%), LDL-C (∼14%), and triglycerides (∼21%), also with no differences between groups (p > 0.05). Gains after retraining were lower than after training (p < 0.05) only for upper- and lower-body muscular strength (∼6%) and testosterone (∼11%). Total cholesterol, high-density lipoprotein cholesterol, IGF-1, and C-reactive protein did not change at any point in the study for either group (p > 0.05). Our results suggest that older women can regain previous RT program benefits following detraining, regardless of the weekly training frequency. However, some fitness components may take longer to reestablish than the initial training level. [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]

The purpose of this study was to analyze the effects of resistance training (RT) exercise order on muscle strength, hypertrophy, and anabolic hormones in older women. Forty-four older women were randomly assigned to 1 of 3 groups: a nonexercise control group (CON, n = 15) and two RT groups that performed a 12-week RT program in a multijoint to single-joint order (MJ-SJ, n = 14), or in a single-joint to multijoint order (SJ-MJ, n = 15). The RT protocol (33/week) encompassed 8 exercises, with 3 sets of 10-15 repetitions performed per exercise. One repetition maximumtests were used to evaluate muscle strength; dual-energy X-ray absorptiometry was used to estimate lean soft tissue. Both training groups showed significant and similar increases in muscle strength (MJ-SJ = 16.4%; SJ-MJ = 12.7%) and mass (MJ-SJ = 7.5%; SJ-MJ = 6.1%), whereas there were no significant changes in testosterone and insulin-like growth factor 1. The results suggest that both approaches are similarly effective in eliciting morphofunctional improvements in older women. [ABSTRACT FROM AUTHOR]

This study aimed to examine the independent and combined effects of pubertal and weight status on concurrent measurements of peak oxygen (...O2peak) in school-aged adolescent males. The final sample included 49 boys (12.3 ± 0.8 years). /O2peak was derived from an incremental progressive maximal protocol using a motorized treadmill. In addition, maximal oxygen uptake was estimated from a 20-m shuttle run test. Static allometric models were obtained as an alternative to performance output per unit of size descriptors. Weight status had a significant effect on ...O2peak using simple ratio standards per unit of body mass (BM) with adolescents classified as overweight and obese (OWOB) attaining lower values of ...O2peak. A similar trend was noted for the allometric models adopting body mass (ml⋅kgBM-0.542⋅min-1), stature (L⋅m-2.602⋅min), and fat-free mass (FFM; ml⋅kgFFM-0.907⋅min-1). Findings also suggest the influence and interaction of pubertal and weight status on absolute values of ...O2peak. Considering the data obtained, linear equations to estimate /O2peak from the 20-m shuttle run test should not be applied to boys who are OWOB because it will produce inaccurate assessments of cardiorespiratory fitness and penalize those who are heavier. Equations for ...O2peak prediction need to be specific for pubertal status and preferably consider FFM as a body size descriptor. [ABSTRACT FROM AUTHOR]

Nascimento, MA, Silva, DRP, Ribeiro, AS, Pina, FLC, Gerage, AM, Gobbo, LA, Mayhew, JL, and Cyrino, ES. Agreement between bioelectrical impedance and dual-energy x-ray absorptiometry to track changes in fat-free mass after resistance training in older women. J Strength Cond Res 34(6): 1700–1708, 2020—The aim of our study was to compare the agreement between bioelectrical impedance (BIA) and dual-energy X-ray absorptiometry (DXA) to track changes on fat-free mass (FFM) after a resistance training (RT) program in older women. Forty-three older women (65.2 ± 4.6 years, 59.5 ± 9.2 kg, 156.4 ± 6.0 cm, 24.3 ± 3.3 kg.m-2) participated in a RT intervention (12 weeks, 8 exercises, 2 sets, 10–15 repetitions, 3 nonconsecutive days per week). Fat-free mass changes were determined by a single-frequency BIA device (EQ1), 6 BIA prediction equations for older women (EQ2, EQ3, EQ4, EQ5, EQ6, and EQ7), and DXA. At pretraining, 3 equations overpredicted, and 3 underpredicted DXA FFM (F = 244.63, p < 0.001), although all equations had high correlations with DXA (r = 0.78–0.83). After training, 4 equations overpredicted and one underpredicted DXA FFM (F = 176.25, p < 0.001). Dualenergy X-ray absorptiometry detected significant gains in FFM (0.65 ± 0.82 kg; p < 0.05), as did EQ3 (0.55 ± 1.69 kg; p < 0.05), and EQ4 (0.61 ± 1.88 kg; p < 0.05), whereas the remaining equations did not indicate significant changes in FFM. Low correlations between FFM and equation change values suggest that single-frequency BIA-derived equations may not provide sufficient accuracy to track changes in FFM after 12 weeks of RT in older women. [ABSTRACT FROM AUTHOR]

This study examined the relationship between PhA and short-term maximal intensity efforts in soccer players, and was conducted in 99 male soccer players, ages 19–36 years. Bioelectrical impedance was used to assess body fat, fat free mass (FFM) and PhA (phase angle). Running Anaerobic Sprint Test (RAST) was used to evaluate physical performance. Food consumption was assessed through the 24-hour dietary recall method. Pearson correlation and multiple regressions were used for statistical analysis. Phase angle exhibited a positive relationship with maximum power (β=0.66; P<0.001), even after adjustment for the co-variables FFM and body fat (β=0.52; P=0.02). Phase angle was inversely related with fatigue index (β=− 0.61; P=0.04), even after adjusting for FFM (β=− 0.70; P=0.020). Our results indicated that independently of FFM and body fat, PhA was inversely associated with fatigue index and positively related with maximum power, revealing the PhA appeared as a valid predictor of fatigue. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyze the effects of resistance training (RT) performed with 1 or 3 sets per exercise on osteosarcopenic obesity (OSO) syndrome parameters in older women. Sixty-two older women (68.0 ± 4.3 years, 26.8 ± 4.4 kg/m2) participated in a 12-week RT program. Participants were randomly assigned into one of the three groups: two training groups that performed either 1 set (G1S, n = 21) or 3 sets (G3S, n = 20) 3 times weekly, or a control group (CG, n = 21). Body composition was assessed by dual X-ray absorptiometry, strength was evaluated by 1 repetition maximum testing. The G3S presented significantly higher strength changes than G1S. The changes for percentage of body fat were higher for G3S compared to G1S. There was no difference in skeletal muscle mass between G3S and G1S, however both training groups displayed greater increases in this outcome compared to CG. There was no effect for bone mineral density. The overall analysis indicated higher (P < 0.05) positive changes for G3S than G1S (composed Z-score: G3S = 0.62 ± 0.40; G1S = 0.11 ± 0.48). The results suggest that a 12-week RT period is effective to improve the risk factors of OSO, and that 3 sets induce higher improvements than a single set. [ABSTRACT FROM AUTHOR]

Objective: The purpose of the present study was to analyze whether improvements in fast walking speed induced by resistance training (RT) are associated with changes in body composition, muscle quality, and muscular strength in older women.Methods: Twenty-three healthy older women (69.6 ± 6.4 years, 64.95 ± 12.9 kg, 1.55 ± 0.07 m, 27.06 ± 4.6 kg/m²) performed a RT program for 8 weeks consisting of 8 exercises for the whole body, 3 sets of 10–15 repetitions maximum, 3 times a week. Anthropometric, body composition (fat-free mass [FFM], skeletal muscle mass [SMM], legs lean soft tissue [LLST], fat mass), knee extension muscular strength (KE1RM), muscle quality index (MQI [KE1RM/LLST]), and 10-meter walking test (10-MWT) were performed before and after the intervention.Results: Significant (P < .05) changes were observed from pre- to post-training for FFM (+1.6%), MQI (+7.2%), SMM (+2.4%), LLST (+1.8%), KE1RM (+8.6%), fat mass (−1.4%), and time to perform 10-MWT (−3.7%). The percentage change in 10-MWT was significantly associated with percentage change in MQI (r = −0.46,P = .04) and KE1RM (r = −0.45,P = .04), however not associated percentage of changes in SMM (r = 0.01,P = .97), LLST (r = −0.22,P = .33), and body fat (r = 0.10,P = .66).Conclusion: We conclude that the improvement in the 10-MWT after an 8-week RT program is associated with increases in lower limb muscular strength and muscle quality, but not with muscle mass or body fat changes in older women. [ABSTRACT FROM PUBLISHER]

• The phase angle (PhA) may have relevant practical application. • The bioimpedance spectroscopy can monitoring the bone health. • Men and women showing a different relationship between PhA and bone health. This study aimed to investigate the relationship between crude bioimpedance variables with bone mineral density (BMD) in older adults. One hundred eighty-four older men and women (≥ 60 years old) composed the sample. BMD (whole-body) was measured through dual-energy X-ray absorptiometry. Bioimpedance spectroscopy was used to estimate whole-body resistance and reactance as well as to calculate the phase angle (PhA) and fat-free mass (FFM). Age, gender, body mass, FFM, height, calcium intake, vitamin D intake, number of fractures, number of diseases, and number of medications were included as covariates in the regression analyses. BMD fractions were significantly (P < 0.01) associated with PhA (femur: r = 0.524; neck: r = 0.450; and forearm: r = 0.437). Independently of age, body mass, FFM, calcium intake, vitamin D, number of diseases, fratures and medications, PhA remains a significant explanator of the variability of total (β = 0.22; P < 0.001), femur (β = 0.10; P = 0.018), and neck BMD (β = 0.07; P = 0.05) for men, and total (β = 0.08; P = 0.002), femur (β = 0.06; P = 0.005), neck (β = 0.04; P = 0.03), and forearm BMD (β = 0.05; P = 0.004) for women. Our results suggest that a higher PhA is associated with BMD in older men and women fractions regardless of relevant covariates highlighting the biological meaning of this simple and crude bioimpedance-based measure in the elderly population. [ABSTRACT FROM AUTHOR]