Validity of the two-minute walk test to assess exercise capacity and estimate cardiorespiratory fitness in individuals after stroke: a cross-sectional study

ABSTRACT

Objectives

The purpose of this study was to investigate the construct validity of the 2-minute walk test (2MWT) to assess the exercise capacity and the criterion-concurrent validity of the 2MWT and the 6-minute walk test (6MWT) to estimate the cardiorespiratory fitness of ambulatory individuals with chronic stroke. In addition, to provide an equation to predict the distance covered in the 6MWT and another to predict the peak oxygen consumption (VO_2peak) for these individuals.

Methods

This is a cross-sectional and prospective study. A convenience sample with 57 individuals with chronic stroke was recruited. The 2MWT, the 6MWT and the cardiopulmonary exercise test (CPET) were performed in a laboratory. The Spearman’s correlation coefficient was used to investigate the validity. To develop the equations, stepwise multiple linear regression analysis was used.

Results

A significant correlation of very high magnitude between the distance covered in the 2MWT and the 6MWT was found (r_s = 0.93; p < 0.001). A significant correlation of moderate magnitude between the distance covered in the 2MWT and the VO_2peak (r_s = 0.53; p < 0.001) similar to the correlation between the 6MWT and the VO_2peak (r_s = 0.55; p < 0,001) were found. Furthermore, an equation was developed to predict the VO_2peak (R² = 0.690; p < 0.001; VO_2peak = 13.532 + 0.078*distance walked in the 2MWT +4.509*sex-0.172*age), and another to predict the distance covered in the 6MWT (R² = 0.827; p < 0.001; MWT = −1.867 + 3.008*distance walked in the 2MWT).

Conclusion

2MWT showed adequate construct and concurrent validity. Furthermore, it is possible to use the prediction equations developed to estimate the VO_2peak or the distance covered in the 6MWT.

KEYWORDS:

• Two-minute walk test
• cardiopulmonary exercise test
• exercise capacity
• cardiorespiratory fitness
• stroke

Geolocation information

Escola de Educação Física, Fisioterapia e Terapia Ocupacional, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. (−19.875837°S, −43.975869°W).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior), FAPEMIG (Fundação de Amparo à Pesquisa do Estado de Minas Gerais), CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico- Finance code 001), PRPq/UFMG (Pró-reitoria de Pesquisa da Universidade Federal de Minas Gerais).