RESUMO
PURPOSE: The optimal intensity of resistance training (RT) to improve muscular, physical performance, and metabolic adaptations still needs to be well established for older adults. Based on current position statements, we compared the effects of two different RT loads on muscular strength, functional performance, skeletal muscle mass, hydration status, and metabolic biomarkers in older women. METHODS: One hundred one older women were randomly allocated to perform a 12-wk whole-body RT program (eight exercises, three sets, three nonconsecutive days a week) into two groups: 8-12 repetitions maximum (RM) and 10-15RM. Muscular strength (1RM tests), physical performance (motor tests), skeletal muscle mass (dual-energy X-ray absorptiometry), hydration status (bioelectrical impedance), and metabolic biomarkers (glucose, total cholesterol, HDL-c, HDL-c, triglycerides, and C-reactive protein) were measured at baseline and posttraining. RESULTS: Regarding muscular strength, 8-12RM promoted higher 1RM increases in chest press (+23.2% vs +10.7%, P < 0.01) and preacher curl (+15.7% vs +7.4%, P < 0.01), but not in leg extension (+14.9% vs +12.3%, P > 0.05). Both groups improved functional performance ( P < 0.05) in gait speed (4.6%-5.6%), 30 s chair stand (4.6%-5.9%), and 6 min walking (6.7%-7.0%) tests, with no between-group differences ( P > 0.05). The 10-15RM group elicited superior improves in the hydration status (total body water, intracellular and extracellular water; P < 0.01), and higher gains of skeletal muscle mass (2.5% vs 6.3%, P < 0.01), upper (3.9% vs 9.0%, P < 0.01) and lower limbs lean soft tissue (2.1% vs 5.4%, P < 0.01). Both groups improved their metabolic profile. However, 10-15RM elicited greater glucose reductions (-0.2% vs -4.9%, P < 0.05) and greater HDL-c increases (-0.2% vs +4.7%, P < 0.01), with no between-group differences for the other metabolic biomarkers ( P > 0.05). CONCLUSIONS: Our results suggest that 8-2RM seems more effective than 10-15RM for increasing upper limbs' muscular strength, whereas the adaptative responses for lower limbs and functional performance appear similar in older women. In contrast, 10-15RM seems more effective for skeletal muscle mass gains, and increased intracellular hydration and improvements in metabolic profile may accompany this adaptation.
Assuntos
Treinamento Resistido , Humanos , Feminino , Idoso , Treinamento Resistido/métodos , Músculo Esquelético/fisiologia , Força Muscular/fisiologia , Glucose/metabolismo , Biomarcadores/metabolismoRESUMO
PURPOSE: Resistance training (RT) combined with appropriate dietary intake can promote a concomitant increase in skeletal muscle mass (SMM) and reduction in fat mass, a condition termed body recomposition. This study's primary purpose was to explore the effects of protein ingestion on body recomposition after 24 wk of RT in older women. METHODS: Data from 130 untrained older women (68.7 ± 5.6 yr, 66.5 ± 11.5 kg, 155.5 ± 6.0 cm, and 27.4 ± 4.0 kg·m-2) across six studies were retrospectively analyzed. The participants were divided into tertiles according to their customary protein intake (g·kg-1·d-1): lower (LP; n = 45), moderate (MP; n = 42), and higher (HP; n = 43) protein intake. Participants performed a whole-body RT program carried out over 24 wk (eight exercises, three sets, 8-15 repetitions, three sessions a week). SMM and fat mass were determined by dual-energy x-ray absorptiometry. RESULTS: All groups increased SMM from baseline (P < 0.05), with the HP and MP groups showing greater increases than the LP group (LP, 2.3%; MP, 5.4%; and HP, 5.1%; P < 0.05). Reductions in fat mass were similar for all three groups (LP, 1.7%; MP, 3.7%; and HP, 3.1%; P > 0.05). The composite z-score of the percentage changes from pretraining to posttraining indicated greater positive body recomposition values for HP and MP compared with LP (P < 0.05). CONCLUSIONS: Results suggest that protein intake is a moderating variable for body recomposition in older women undergoing RT, with a low protein intake having a less favorable effect on body recomposition.
Assuntos
Treinamento Resistido , Absorciometria de Fóton , Idoso , Composição Corporal/fisiologia , Proteínas Alimentares , Feminino , Humanos , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Estudos RetrospectivosRESUMO
This study analyzed the effects of the pyramidal resistance training (RT) system with two repetition zones on cardiovascular risk factors in older women (≥60 years old). Fifty-nine older women were randomly assigned in three groups: non-exercise control (CON, n = 19), narrow-pyramid system (NPR, n = 20), and wide-pyramid system (WPR, n = 20). Training was performed for eight weeks (eight exercises for the whole-body, 3x/week) in which NPR and WPR performed three sets of 12/10/8 and 15/10/5 repetitions, respectively. Regional body fat was estimated by dual-energy X-ray absorptiometry, and blood parameters related to glycemic, lipid, and inflammatory profiles were assessed. After the training period, although no difference was observed for the magnitude of the changes between NPR and WPR, significant group by time interactions indicated benefits with RT compared to CON for reducing body fat (mainly android body fat; -7%) and improving glucose, HDL-C, LDL-C and C-reactive protein (p < 0.05). Composite z-score of cardiovascular risk, created by the average of the intervention effects on the outcomes, indicate similar responses between NPR and WPR, differing from CON (p < 0.001). Results indicate that both the repetition zones of the pyramidal RT reduced similarly the cardiovascular risk in older women.
Assuntos
Doenças Cardiovasculares , Treinamento Resistido , Idoso , Composição Corporal , Doenças Cardiovasculares/prevenção & controle , Exercício Físico , Feminino , Humanos , Pessoa de Meia-Idade , Força Muscular , Fatores de RiscoRESUMO
BACKGROUND: Oxidative stress is an imbalance between antioxidant system and production of free radicals and has been associated with the age-related deleterious changes. The defense system can be modulated by exercise and nutrition. OBJECTIVE: The purpose of this investigation was to evaluate the effect of whey protein supplementation pre- or post-resistance training on oxidative stress and antioxidant enzyme activity in pre-conditioned older women. METHODS: In a randomized, double-blind, and placebo-controlled design, 70 older women (≥60 years) were randomly assigned to one of the following three groups: whey protein-placebo (WP-PLA, n = 24), placebo-whey protein (PLA-WP, n = 23), and placebo-placebo (PLA-PLA, n = 23). Each group received 35 g of whey product or placebo pre- and post-training. The RT program was carried out over 12 weeks (3x/week; 3x 8-12 repetitions maximal). Oxidative stress and blood markers were assessed before and after intervention period. ANOVA for repeated measures was used for data analysis. RESULTS: There was a significant time effect (P < 0.05), with all groups showing improvements in all oxidative stress markers and antioxidant enzyme activity. A significant (P < 0.001) interaction time vs group was observed for uric acid, with both WP-PLA and PLA-WP presenting greater reductions compared with the PLA-PLA, without differences between the timing of protein intake (WP-PLA: -8.3%; PLA-WP: -11.0%; PLA-PLA:-2.0%). CONCLUSION: In already pre-conditioned older women, whey protein supplementation reduces plasma uric acid concentration with no further effect on antioxidant enzyme activity and oxidative stress markers. ClinicalTrials.gov: NCT03247192.
Assuntos
Antioxidantes/metabolismo , Suplementos Nutricionais , Estresse Oxidativo , Treinamento Resistido , Proteínas do Soro do Leite/administração & dosagem , Idoso , Biomarcadores/sangue , Catalase/sangue , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Superóxido Dismutase/sangueRESUMO
Aging is associated with sarcopenia and dynapenia, with both processes contributing to functional dependence and mortality in older adults. Resistance training (RT) and increased protein intake are strategies that may contribute to health improvements in older adults. Therefore, the aim was to investigate the effects of whey protein (WP) supplementation consumed either immediately pre- or post-RT on skeletal muscle mass (SMM), muscular strength, and functional capacity in pre-conditioned older women. Seventy older women participated in this investigation and were randomly assigned to one of three groups: whey protein pre-RT and placebo post-RT (WP-PLA, n = 24), placebo pre-RT and whey protein post-RT (PLA-WP, n = 23), and placebo pre- and post-RT (PLA-PLA, n = 23). Each group ingested 35 g of WP or PLA. The RT program was carried out over 12 weeks (three times per week; 3 × 8â»12 repetition maximum). Body composition, muscular strength, functional capacity, and dietary intake were assessed pre- and post-intervention. Two-way analysis of covariance (ANCOVA) for repeated measures, with baseline scores as covariates were used for data analysis. A time vs. group interaction (p < 0.05) was observed with WP-PLA and PLA-WP presenting greater increases compared with PLA-PLA for SMM (WP-PLA = 3.4%; PLA-WP = 4.2%; PLA-PLA = 2.0%), strength (WP-PLA = 8.1%; PLA-WP = 8.3%; PLA-PLA = 7.0%), and the 10-m walk test (WP-PLA = −10.8%; PLA-WP = −11.8%; PLA-PLA = −4.3%). Whey protein supplementation was effective in promoting increases in SMM, muscular strength, and functional capacity in pre-conditioned older women, regardless of supplementation timing. This trial was registered at ClinicalTrials.gov: NCT03247192.
Assuntos
Envelhecimento , Força Muscular , Músculo Esquelético/fisiologia , Treinamento Resistido , Proteínas do Soro do Leite/administração & dosagem , Absorciometria de Fóton , Composição Corporal , Índice de Massa Corporal , Brasil , Dieta , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-IdadeRESUMO
The aim of this study was to analyze the effects of 8 weeks of conjugated linoleic acid (CLA) supplementation associated with aerobic exercise on body fat and lipid profile on obese women. We performed a randomized, double-blinded and placebo-controlled trial with 28 obese women who received 3.2 g/day of CLA or 4 g/day of olive oil (placebo group) while performing an 8-week protocol of aerobic exercise. Dietary intake (food record), body fat (dual-energy X-ray absorptiometry), and biochemical analysis (blood sample) were assessed before and after the intervention period. Independent of CLA supplementation, both groups improved (p < .05) oxygen uptake (CLA group, 13.2%; PLC group, 14.8%), trunk fat (CLA group, -1.0%; PLC group, -0.5%), leg fat (CLA group, -1.0%; PLC group, -1.6%), and total body fat (CLA group, -1.7%; PLC group, -1.3%) after the 8-week intervention. No main effect or Group × Time interaction was found for total cholesterol, triglycerides, and plasma lipoproteins (p > .05). We conclude that CLA supplementation associated with aerobic exercise has no effect on body fat reduction and lipid profile improvements over placebo in young adult obese women.