Walking tests during the exercise training: Specific use for the cardiac rehabilitation

Abstract

Walk tests, principally the six-minute walk test (6mWT), constitute a safe, useful submaximal tool for exercise tolerance testing in cardiac rehabilitation (CR). The 6mWT result reflects functional status, walking autonomy and efficacy of CR on walking endurance, which is more pronounced in patients with low functional capacity (heart failure - cardiac surgery). The 6mWT result is a strong predictor of mortality. However, clinically significant changes and reliability are still subject to debate - probably because of the ambiguity in terms of the target speed (either comfortable or brisk walking). Of the other time-based walk tests, the 2-minute-walk test is the only one applicable during CR, reserved for patients with severe disabilities by its psychometric properties. Fixed-distance tests (principally the 200m fast walk test) and incremental shuttle walking, tests explore higher levels of effort and may represent a safe and inexpensive alternative to laboratory-based tests during CR. These walking tests may be useful for personalizing prescription of training programs. However, the minimum clinically significant difference has not yet been determined. Lastly, walking tests appear to be potential useful tools in promoting physical activity and behavioural changes at home. Thus, validation of other walk tests with better psychometric properties will be necessary.

Outcome Measures in Clinical Practice: Five Questions to Consider When Assessing Patient Outcome

“…But, to what extent does the 6MWT accurately reflect functional aerobic capacity as compared to the 'gold standard' CPET? The review by Casillas et al [19] noted the 6MWT to be well correlated with both the maximum power reached during a cycle CPET (correlation = 0.93) and VO 2 peak (correlation estimates varied from 0.50 to 0.82) [20]. With moderate to high correlation values, we can be confident that the 6MWT reasonably represents exercise tolerance and aerobic capacity, and displays a high level of validity in patients with CVD.…”

“…Example: Patients with cardiovascular disease (CVD) are often quite limited in physical activity resulting from an intolerance to exercise as part of their disease burden [19]. Cardiac rehabilitation is an important component of increasing functional capacity and improving quality of life.…”

“…To appropriately prescribe an exercise program, testing to determine exercise tolerance and aerobic capacity is required. However, many patients with severe CVD are unable to participate in maximal cardiopulmonary exercise testing (CPET) [19], and CPET is not necessarily representative of real-life functional capacity [19]. As a result, more functional, submaximal field tests have come into favor, including the 6MWT.…”

“…Example: If a patient with CVD walks 300 m or less, this can be interpreted as having poor exercise tolerance (and is associated with poor prognosis) [19] compared to age and sex-matched population norms of 494 and 576 m for healthy women and men, respectively [21]. We consider two aspects of change.…”

Are first ventilatory threshold and 6-minute walk test heart rate interchangeable? A pilot study in healthy elderlies and cardiac patients

“…Other easier and faster testing modalities thus appear useful to evaluate patients at various submaximal levels that are more relevant to daily activities [13,14] Even if there are still no recommendations regarding potential alternatives to CPET, functional evaluations, such as walk tests are thus being more and more used. The 6-min walk test (6-MWT) is now widely proposed to assess functional exercise capacity and prognosis since it is reproducible, well tolerated and corresponds to submaximal moderate exercise.…”