Determining the engergy expenditure and relative intensity of two crossfit workouts

Abstract

This study was designed to determine the energy expenditure and relative intensity of two Crossfit workouts. Fifteen subjects (7 males, 8 females) performed a VO2max test before participating in the CrossFit workouts. Additionally, subjects completed two different CrossFit workouts, which included a similar number of sets and repetitions. Each workout included a 5-minute warm-up, a skill phase, a workout of the day (WOD), and a 5-minute cool-down phase. During the CrossFit workouts heart rate was measured every minute using radiotelemetry. Subjects reported rating of perceived exertion (RPE) after each set of exercises and upon completion of the workout using the 6-20 Borg scale. Males had a significantly higher VO2, session RPE, and energy expenditure during both workouts compared to females. Heart rates were elevated to 90% of HRmax, and VO2 reached 80% VO2max in both workouts. Both values fall within the training range recommended by ACSM for improving cardiorespiratory endurance.