Efetividade do treinamento de resistência à fadiga dos músculos dos membros inferiores dentro e fora d'água no equilíbrio estático e dinâmico de idosos Effectiveness of aquatic and non-aquatic lower limb muscle endurance training in the static and dynamic balance of elderly people

CONTEXTUALIZAÇÃO: O envelhecimento compromete a habilidade do sistema nervoso central (SNC) de realizar a manutenção do equilíbrio corporal bem como diminui a capacidade das reações adaptativas. Para prevenir as quedas, é necessário aprimorar as condições de recepção de informações sensoriais. OBJETIVOS: Comparar o impacto de um programa estruturado de exercícios de resistência muscular dos membros inferiores dentro e fora d'água no equilíbrio estático e dinâmico em idosos. MÉTODOS: Trata-se de um estudo clínico, prospectivo, aleatório, em que as variáveis utilizadas foram avaliadas antes e após o programa de treinamento. Foram avaliados 36 idosos por meio de quatro testes: Escala de Equilíbrio de Berg, Dynamic Gait Index, velocidade da marcha, Marcha Tandem. Posteriormente, houve a alocação dos voluntários em três grupos: grupo de exercício na piscina terapêutica, grupo de exercício no solo e grupo controle. Os grupos de exercícios foram submetidos a um programa de resistência muscular dos membros inferiores aplicado durante seis semanas, duas sessões semanais com 40 minutos de duração. Os voluntários foram reavaliados após seis semanas. Os dados foram analisados estatisticamente pelo teste ANOVA univariada para comparação entre os três grupos antes e após a intervenção. RESULTADOS: O programa de resistência muscular dos membros inferiores promoveu aumento significativo do equilíbrio dos idosos (p<0,05) nos testes avaliados após o programa de treinamento. CONCLUSÃO: O programa de resistência muscular proporcionou uma melhora significativa no equilíbrio estático e dinâmico de idosos comunitários. Foi possível inferir também que essa melhora ocorreu independentemente do meio em que o programa foi realizado, ou seja, se dentro ou fora d'água.<br>BACKGROUND: Aging compromises the ability of the central nervous system to maintain body balance and reduces the capacity for adaptive reactions. To prevent falls, the reception conditions for sensory information need to be improved. OBJECTIVES: To evaluate the impact of a structured aquatic and a non-aquatic exercise program for lower-limb muscle endurance on the static and dynamic balance of elderly people. METHODS: This was a prospective randomized clinical study in which the variables were assessed before and after the training program. Thirty-six elderly people were evaluated using four tests: the Berg Balance Scale, Dynamic Gait Index, gait speed and tandem gait. The participants were randomized into three groups: aquatic exercise group, non-aquatic exercise group and control group. The exercise groups underwent a program for lower-limb muscle endurance that consisted of 40-minute sessions twice a week for six weeks. The participants were reevaluated after six weeks. The data were analyzed statistically using the univariate ANOVA test for comparisons between the groups before and after the intervention. RESULTS: The program for lower-limb muscle endurance significantly increased balance (p<0.05) in the evaluation tests after the training program. CONCLUSION: The muscle endurance program provided a significant improvement in static and dynamic balance among community-dwelling elderly people. It was also possible to infer that this improvement occurred regardless of the environment, i.e. aquatic or non-aquatic

Cardiorespiratory responses and prediction of peak oxygen uptake during the shuttle walking test in healthy sedentary adult men.

BACKGROUND:The application of the Shuttle Walking Test (SWT) to assess cardiorespiratory fitness and the intensity of this test in healthy participants has rarely been studied. This study aimed to assess and correlate the cardiorespiratory responses of the SWT with the cardiopulmonary exercise testing (CEPT) and to develop a regression equation for the prediction of peak oxygen uptake (VO2 peak) in healthy sedentary adult men. METHODS:In the first stage of this study, 12 participants underwent the SWT and the CEPT on a treadmill. In the second stage, 53 participants underwent the SWT twice. In both phases, the VO2 peak, respiratory exchange ratio (R), and heart rate (HR) were evaluated. RESULTS:Similar results in VO2 peak (P>0.05), R peak (P>0.05) and predicted maximum HR (P>0.05) were obtained between the SWT and CEPT. Both tests showed strong and significant correlations of VO2 peak (r = 0.704, P = 0.01) and R peak (r = 0.737, P<0.01), as well as the agreement of these measurements by Bland-Altman analysis. Body mass index and gait speed were the variables that explained 40.6% (R2 = 0.406, P = 0.001) of the variance in VO2 peak. The results obtained by the equation were compared with the values obtained by the gas analyzer and no significant difference between them (P>0.05) was found. CONCLUSIONS:The SWT produced maximal cardiorespiratory responses comparable to the CEPT, and the developed equation showed viability for the prediction of VO2 peak in healthy sedentary men

Comparison between the results of cardiorespiratory variables and RPE at the end of the test, obtained in SWT and CEPT.

<p>The data is presented as mean (SD). *<i>P</i><0.05. SWT = Shuttle Walking Test; CEPT = cardiopulmonary exercise testing; VO₂ = oxygen uptake; R = respiratory exchange ratio; HR = heart rate; RPE = rating of perceived exertion. ^†Paired-t test; ^¥Wilcoxon test.</p><p>Comparison between the results of cardiorespiratory variables and RPE at the end of the test, obtained in SWT and CEPT.</p

General characteristics of the participants of the second stage.

<p>The data is presented as mean (SD). BMI = body mass index. HR = heart rate.</p><p>General characteristics of the participants of the second stage.</p

Agreement between VO2 peak and R peak obtained in the SWT and CEPT.

<p>Bland-Altman plot of the difference between the VO₂ peak of the SWT and CEPT plotted against the mean VO₂ peak of the SWT and CEPT (A) and difference R peak of the SWT and CEPT plotted against the mean R peak of the SWT and CEPT (B). SWT = Shuttle Walking Test; CEPT = cardiopulmonary exercise testing; VO₂ = oxygen uptake; R = respiratory exchange ratio.</p