This study was performed to investigate the relationship between heart rate (HR) as a percentage of peak HR and oxygen uptake (V̇O2) as a percentage of peak V̇O2 in older adults while performing deep water running (DWR). Twenty-three (14 male and 9 female) apparently healthy older adults, age 50 to 70 years, volunteered. Deep water running to V̇O2peak was performed in 3-min stages at leg speeds controlled by a metronome beginning at 60 strides per minute and increasing 12 strides per minute each additional stage. Oxygen uptake and HR were continuously monitored by open-circuit spirometry and radiotelemetry, respectively. Simple linear regression analysis was used to establish the relationship between the physiological variables. The relationship between %V̇O2peak and %HRpeak was statistically significant, with the male (%V̇O2peak = 1.5301 [%HRpeak] − 54.4932 [r = .96, SEE = 6.0%]) and female (%V̇O2peak = 1.5904 [%HRpeak] - 62.3935 [r = .91, SEE = 6.9%]) regression equations being significantly different (p < .05). The regression equations of older adults and those for college-aged males (%VO2peak = 1.4634 [%HRpeak] − 49.619) and females (%V̇O2peak = 1.6649 [%HRpeak] − 67.862) were not significantly different.
The authors are with the Applied Physiology Laboratory, Department of Exercise Science and Leisure Management, The University of Mississippi, University, MS 38677.