RESUMO
The purpose of the present study was to examine the association between fat-free mass (FFM), quadriceps strength and sarcopenia with aerobic fitness indexes of elderly women. A total of 189 volunteers (66.7 ± 5.46 years) underwent aerobic capacity measurement through a symptom-limited cardiopulmonary exercise test to determine their individual ventilatory thresholds (VT) and peak oxygen uptake (VO2 peak). Quadriceps muscle strength was assessed using an isokinetic dynamometer. Also, dual energy X-ray absorptiometry was used to assess FFM and cutoff values were used to classify subjects as sarcopenic or nonsarcopenic. Correlations, student t-test and analysis of variance were used to examine the data. Both FFM and quadriceps strength variables were positively and significantly correlated with the measured aerobic capacity indexes. These results were observed for peak exercise as well as for ventilatory thresholds. Individuals classified as sarcopenic presented significantly lower muscle strength and (VO2 peak) when compared to nonsarcopenic. It can be concluded that FFM and quadriceps strength are significantly related to aerobic capacity indexes in older women, and that besides presenting lower quadriceps strength, women classified as sarcopenic have lower peak oxygen consumption. Taken together, the present results indicate that both FFM and strength play a role in the age-related decline of aerobic capacity. Key pointsMaximal aerobic capacity, generally expressed as peak oxygen consumption (VO2 peak), declines with advancing age and this process is associated with an increased risk for cardiovascular diseases.Also, the aging process is associated with a progressive loss of muscle mass and strength and this phenomenon has been referred to as Sarcopenia. Sarcopenia has been described in both elderly men and women and has been linked to multiple negative clinical outcomes.The present study provide evidence that muscle-related phenotypes are associated with aerobic capacity of older individuals, thus suggesting that sarcopenia explains in part the decline in aerobic fitness observed with advancing age.
RESUMO
INTRODUÇÃO E OBJETIVO: O consumo de oxigênio pico (VO2pico) e o limiar anaeróbio (LA) são amplamente aceitos como importantes medidas da aptidão aeróbia. Tradicionalmente, o treinamento aeróbio é visto como o principal meio de se aumentar esses índices. Em contrapartida, o treinamento resistido (TR) não é tipicamente prescrito para este fim. Em indivíduos idosos, tem sido sugerido que o TR é capaz de aprimorar a capacidade aeróbia; entretanto, a temática é controversa. O objetivo do presente estudo foi verificar os efeitos do treinamento resistido sobre índices da capacidade aeróbia de mulheres idosas. METODOLOGIA: Participaram voluntariamente 50 idosas, as quais foram distribuídas em dois possíveis grupos: grupo controle (GC - n = 25; idade média 68,00 ± 6,38) e grupo treinamento (GT - n = 25; idade média 68,04 ± 6,78 anos). Todas as participantes realizaram teste ergoespirométrico em esteira conduzido até a exaustão voluntária antes e após a intervenção. O GT foi submetido a um programa de TR para os principais grupos musculares três vezes por semana durante um período de 24 semanas. Ao GC foi solicitado que mantivessem suas rotinas habituais. Split plot Anova foi utilizada para verificar possíveis diferenças intra e intergrupos. RESULTADOS: Foi observado que o GT apresentou aumento significativo nas variáveis tempo de teste e VO2, tanto no momento do LA como no momento da exaustão. No GC nenhuma das variáveis dependentes sofreu alteração significativa. CONCLUSÃO: Conclui-se que 24 semanas de TR é capaz de promover melhora no desempenho durante teste de esforço cardiopulmonar em uma amostra de mulheres idosas. Futuros estudos serão importantes para elucidar os mecanismos responsáveis por tais adaptações.
INTRODUCTION AND OBJECTIVES: Peak oxygen uptake (VO2 peak) and anaerobic threshold (AT) have been widely accepted as important predictors of aerobic fitness. Traditionally, aerobic training is viewed as the main way to increase these indices. Conversely, resistance training (RT) is not typically prescribed for this purpose. In elderly subjects, it has been suggested that RT may increase aerobic capacity; however, the literature is controversial. The purpose of the present study was to verify the effects of 24 weeks of RT on aerobic capacity indexes of elderly women. METHOD: Fifty elderly women voluntarily took part in this study and were divided into two possible groups: control group (CG - n=25; mean age of 68.00 ± 6.38 years) and training group (TG - n=25; mean age of 68.04 ± 6.78 years). All volunteers underwent cardiopulmonary exercise test on treadmill until volitional exhaustion before and after the intervention period. A split plot ANOVA test was used to examine differences within and between groups. RESULTS: It was observed that the TG exhibited significant increase in the variables time of test and oxygen uptake for both AT and exhaustion moments. The CG did not show any significant alterations for any of the dependent variables. CONCLUSIONS: It can be concluded that 24 weeks of RT are capable of promoting improvement in performance during a cardiopulmonary exercise test in a sample of elderly women. Further studies are necessary to elucidate the mechanisms responsible for these adaptations.