Abstract: Hulsey, CR, Soto, DT, Koch, AJ, and Mayhew, JL. Comparison of kettlebell swings and treadmill running at equivalent rating of perceived exertion values. J Strength Cond Res 26(5): 1203–1207, 2012—The purpose of this study was to compare metabolic demand of a kettlebell (KB) swing routine with treadmill (TM) running at equivalent rating of perceived exertion (RPE). Thirteen subjects (11 male, 2 female, age = 21.4 ± 2.1 years, weight = 73.0 ± 9.2 kg) completed a 10-minute KB swing routine consisting of 35-second swing intervals followed by 25-second rest intervals. Men used a 16-kg KB, and women used an 8-kg KB. After 48 hours of rest, the subjects completed a 10-minute TM run at equivalent RPEs as measured during the swing workout. Metabolic data were monitored each minute during each exercise using an automated cart, with the final 7 minutes used for analysis. The RPE and heart rate (HR) recorded at minutes 5, 7, 9, and 10 increased by 2–3 and 7–9%, respectively, for each exercise, producing a significantly increasing pattern but no significant difference between exercises. Average HR and RPE were not significantly different between KB and TM and averaged 90 and 89%, respectively, of age-predicted HRmax. Oxygen consumption, METS, pulmonary ventilation, and calorie expenditure were significantly higher for TM (25–39%) than for KB. Respiratory exchange ratio (TM = 0.94 ± 0.04, KB = 0.95 ± 0.05) and respiratory rate (TM = 38 ± 7, KB = 36 ± 4 b·min−1) were not significantly different between the exercises at any time point. During TM and KB exercises matched for RPE, the subjects are likely to have higher oxygen consumption, work at a higher MET level, and burn more kilocalories per minute during TM running than during KB swings. However, according to the American College of Sports Medicine standards, this KB drill could provide sufficient exercise stress to produce gains in aerobic capacity.