Reference values for the incremental shuttle walk test in healthy subjects: from the walk distance to physiological responses

Abstract

OBJECTIVE: To determine reference values for incremental shuttle walk distance (ISWD) and peak physiological responses during the incremental shuttle walk test (ISWT), as well as to develop a series of predictive equations for those variables in healthy adults. METHODS: We evaluated 103 healthy participants ≥ 40 years of age (54 women and 49 men). We fitted each participant with a gas analysis system for use during the ISWT. Oxygen consumption (VO2), carbon dioxide production, minute ventilation, heart rate (HR), ISWD, and maximal walking velocity (MWV) were obtained as primary outcomes. We also assessed hand grip strength (HGS) and lean body mass (LBM). RESULTS: The regression analysis models, including physiological variables, ISWD, and MWV (adjusted for age, body mass, height, and sex), produced R2 values ranging from 0.40 to 0.65 (for HR and peak VO2, respectively). Using the models including LBM or HGS, we obtained no significant increase in the R2 values for predicting peak VO2, although the use of those models did result in slight increases in the R2 values for ISWD and MWV (of 8% and 12%, respectively). The variables ISWD, MWV, and ISWD × body mass, respectively, explained 76.7%, 73.3%, and 81.2% of peak VO2 variability. CONCLUSIONS: Our results provide reference values for ISWD and physiological responses to the ISWT, which can be properly estimated by determining simple demographic and anthropometric characteristics in healthy adults ≥ 40 years of age. The ISWT could be used in assessing physical fitness in the general adult population and in designing individualized walking programs.

Correlation of lung function and respiratory muscle strength with functional exercise capacity in obese individuals with obstructive sleep apnea syndrome

“…(29) Factors such as dyspnea, abnormalities in respiratory mechanics, respiratory muscle dysfunction, and arterial hypoxemia contribute to limiting exercise tolerance in OSAS patients. (14) In our study, the distance covered on both walk tests was lower than the reference distance for healthy individuals in the Brazilian population, (30)(31)(32) indicating that exercise tolerance was below normal in our obese patients with OSAS. The patients in our sample also had comorbidities such as hypertension and type 2 diabetes mellitus.…”

Dynamic physiological responses to the incremental shuttle walk test in adults

“…Instead, the LBM presented positively influence on three of the four studied dynamic relationships. These results are likely to be related to the well-known stroke volume-body mass relationship and to the underlying relationship between lean body mass and regular physical activity (34).…”

Efeito Do Treinamento Resistido No Desempenho Físico E Capacidade Funcional Respiratória De Mulheres Idosas

“…Ao término do teste, além das variáveis fisiológicas já anotadas, registrou-se o estágio no qual o teste foi interrompido e computada a distância percorrida em metros 4 . Para obtenção dos valores de referência do ISWT, foi utilizada a equação 18 : ISWT = 347,7 -(7,2 x Idade) -(3 x Peso) + (472,3 x Altura) + (137,2 x 0).…”

“…É um teste simples, desenvolvido em 1992, incremental e com velocidade controlada por sinais sonoros, o qual tem como finalidade avaliar o desempenho físico do indivíduo 16 . O ISWT foi criado como um instrumento de avaliação para indivíduos com doença pulmonar obstrutiva crônica 4 , porém sua aplicação é possível a indivíduos com diferentes condições de saúde e faixas etárias 17 , podendo ser utilizado na avaliação da capacidade física da população de adultos em geral 18 e, particularmente, em indivíduos idosos. Em síntese, com o passar dos anos, indivíduos idosos tendem à redução da força geral e encontram no TR alternativa metodológica à manutenção das condições apropriadas para o trofismo muscular em geral 19 e, possivelmente, ao desenvolvimento da capacidade funcional respiratória.…”