Evaluating the two-minute walk test as a time-efficient alternative to the six-minute walk test in Nigerian older adults: Insights from an exploratory mediation and moderation analysis

• A 2-minute walk test can be used instead of the 6-minute walk test for people who have high cardiovascular endurance. • Replacing the 6-minute walk test with a 2-minute walk test is not advisable for people with low cardiovascular endurance. • The choice between a 2-minute and a 6-minute walk test does not depend on age, sex at birth, or cognitive status of the older adults. This study aimed to test whether the 2-Minute Walk Test (2MWT) can substitute for the 6-Minute Walk Test (6MWT) when estimating functional capacity in Nigerian older adults and to identify physiological mediators or moderators of that relationship. We conducted a cross-sectional study and recruited 409 adults ≥ 60 years who completed both walk tests; gait speed was the primary outcome. Age, sex, body-mass index (BMI), Montreal Cognitive Assessment scores, and estimated VO₂ max were also recorded. This study indicated that 2MWT gait speed strongly predicted 6MWT gait speed (β = 0.547, p < 0.001), accounting for 35 % of its variance. Age, cognition, BMI, and VO₂ max did not mediate this association, but VO₂ max moderated it (interaction β = 0.0175, p < 0.05). Bland–Altman analysis showed a small systematic underestimation by the 2MWT, with acceptable agreement when mean speeds were 0.7–1.2 m s⁻¹. We concluded that the 2MWT could offer a time-efficient proxy for the 6MWT in low-resource settings, although clinicians should interpret results cautiously in individuals with low aerobic fitness.