Cardiometabolic and perceptual responses to maximal exercise: Comparing graded walking to running

Abstract

Graded exercise testing on a treadmill can be accomplished by increasing speed and/or grade. The purpose of this study was to compare cardiometabolic responses during graded walking and ungraded running. Thirty healthy, active adults (21 females, 9 males; VO2peak = 39.9 ± 5.4 ml/kg/min) completed two counterbalanced maximal exercise tests (Walk Max & Run Max). Walk tests started at a self-selected brisk speed, increased grade by 2% each minute. Run tests started at 3.5 mph and increased speed by 0.5 mph each minute. Expired gases, HR, overall RPE (RPE-O), legs only RPE (RPE-L), and RER were assessed. Data were analysed using dependent t-tests. Walk Max and Run Max protocols yielded results indicating maximal effort. VO2 was higher for the Run Max protocol (p < .05; ES = 0.4). RPE-L was higher for the Walk Max protocol (p < .05; ES = 0.4). RPE-O was not different between protocols (p > .05). RER was also higher for the Walk Max protocol (p < .05; ES = 0.7). Total exercise time for both protocols was similar (p > .05). Max protocols delivering work by walking and running are both viable and provide options to suit the circumstances and/or preferences of the patient/client. Walk and run protocols can be appropriate for young, healthy, and active individuals. Walk protocols may limit participant anxiety related to falls and thus has the potential to increase exercise self-efficacy. Walk protocols are also an excellent choice when the participant cannot or should not perform a run-based protocol.