Intensity and physiological responses to the 6-minute walk test in middle-aged and older adults: a comparison with cardiopulmonary exercise testing

Abstract

The 6-minute walk test (6MWT) is a simple field test that is widely used in clinical settings to assess functional exercise capacity. However, studies with healthy subjects are scarce. We hypothesized that the 6MWT might be useful to assess exercise capacity in healthy subjects. The purpose of this study was to evaluate 6MWT intensity in middle-aged and older adults, as well as to develop a simple equation to predict oxygen uptake (V˙O2) from the 6-min walk distance (6MWD). Eighty-six participants, 40 men and 46 women, 40-74 years of age and with a mean body mass index of 28±6 kg/m2, performed the 6MWT according to American Thoracic Society guidelines. Physiological responses were evaluated during the 6MWT using a K4b2 Cosmed telemetry gas analyzer. On a different occasion, the subjects performed ramp protocol cardiopulmonary exercise testing (CPET) on a treadmill. Peak V˙O2 in the 6MWT corresponded to 78±13% of the peak V˙O2 during CPET, and the maximum heart rate corresponded to 80±23% of that obtained in CPET. Peak V˙O2 in CPET was adequately predicted by the 6MWD by a linear regression equation: V˙O2 mL·min-1·kg-1 = -2.863 + (0.0563×6MWDm) (R2=0.76). The 6MWT represents a moderate-to-high intensity activity in middle-aged and older adults and proved to be useful for predicting cardiorespiratory fitness in the present study. Our results suggest that the 6MWT may also be useful in asymptomatic individuals, and its use in walk-based conditioning programs should be encouraged.

Sarcopenia as a Mediator of the Effect of a Gerontogymnastics Program on Cardiorespiratory Fitness of Overweight and Obese Older Women: A Randomized Controlled Trial

“…Aerobic endurance was assessed using the 6-min walk test (6 MWT). The 6 MWT has been shown to be a valid, reliable, objective, inexpensive, and easy test used to evaluate cardiorespiratory capacity [ 56 , 57 , 58 , 59 , 60 ]. It is a simple test to perform and is better related to the person’s daily life activities than other tests [ 58 , 59 ].…”

Correlação entre a distância percorrida em testes de caminhada e o nível de atividade física de adultos e idosos assintomáticos

“…Adicionalmente, os autores 18 detectaram índices de transição entre exercício moderado e intenso no ISWT no qual o modelo de regressão linear revelou forte coeficiente de determinação. Apesar de Sperandio et al 17 terem obtido valores semelhantes em relação ao TC6, o ritmo do exercício é controlado pelo sujeito e atinge-se o estado estável aeróbio, o que resulta em menor recrutamento de fibras musculares glicolíticas.…”

“…O teste de caminhada de 6 minutos (TC6) e o Incremental shuttle walk test (ISWT) estão entre os testes de caminhada de campo mais utilizados, principalmente para medição da capacidade funcional de exercício 14 . A existência de correlação entre a distância percorrida no TC6 e NAFVD, mensurado por acelerometria, é válida como índice de condicionamento aeróbio em pacientes com doenças crônicas, idosos e adultos [15][16][17] .…”

Screening for physical inactivity among adults: the value of distance walked in the six-minute walk test. A cross-sectional diagnostic study

“…Furthermore, the peak V'O 2 in CPET was accurately predicted by the six-minute walking distance (R 2 = 0.76), through the equation derived. 24 Although this tool is suitable for evaluating the functional exercise capacity of the majority of middleaged and older adults, some studies have failed to demonstrate any association between self-reported physical activity and sixminute walking distance. 25,26 This inconsistency may be due to self-reported physical activity.…”