Rationale:

The North Carolina six-minute cycle (6MC) test was designed as an alternative measure of physical performance for cardiac rehabilitation (CR) facilities with limitations that did not allow for appropriate administration of the six-minute walk (6MW) test. Currently, little is known about how this self-paced test compares to the 6MW test from a physiologic perspective, or if gender differences exist between these tests in patients with cardiovascular disease.

Objective:

To compare peak physiologic responses between the 6MC and 6MW tests in older men and women with cardiovascular disease who have recently entered a CR program.

Methodology:

Eighty men and 21 women (mean age = 63.6 +/- 6.7 years) performed 6MC tests on a Schwinn AirDyne(TM) cycle ergometer at the same time of day for three consecutive visits within the first week of CR participation. Distance pedaled was calculated to the nearest 1/100 of a mile and converted to feet. These same participants also performed 6MW tests on their first CR visit. Resting and peak exercise heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), rate-pressure product (RPP), and Borg rating of perceived exertion (RPE) were measured during each test. Physiologic measures of the three 6MC tests were averaged and compared to the mean 6MW values.

Results:

The men's peak HR, SBP, RPP, and RPE responses were greater during the 6MC test than during the 6MW test. No differences were seen in peak HR, SBP, or RPP between tests in women. The women's peak exercise RPE was higher in the 6MC test than in the 6MW test. No differences in DBP were seen between tests in either gender.

Conclusions:

Staff of CR programs may expect higher cardiovascular responses when administering the 6MC test compared to the 6MW test in men, with similar responses noted between tests in women.