Intensity of Curves for Women Workout

Abstract

Curves for Women is the largest fitness franchise in the world with over 8000 locations and 2 million members throughout North America and Europe. The signature 30-minute workout includes a 25-minute circuit (2 rounds of 30-second bouts on 12 hydraulic resistance machines alternating with 30 seconds of stationary jogging, marching, or walking) followed by 5 minutes of stretching. Despite its popularity with consumers, there is a paucity of quantitative information regarding the intensity and energy expenditure related to this exercise session. PURPOSE To quantify the exercise intensity and calorie expenditure of a typical Curves workout. METHODS Apparently healthy women 20–55 yr were recruited from the membership of two local Curves locations. Each subject completed a treadmill VO2max test in addition to 2, 30-minute Curves workouts, performed on separate occasions. For all testing, heart rate was assessed using radiotelemetry and gas exchange was measured via portable metabolic analyzer. RESULTS Fifteen women (43±11 yrs, 78±20 kg, VO2max 29±7 ml/kg/min) participated in the study. During the circuit portion of the workout, oxygen consumption averaged 17±3 ml/kg/min (59±7% of VO2max, range 47–68%), heart rate averaged 126±12 bpm (75±7% of HRmax, range 63–83%), and RPE averaged 13.3 (range 12.3–14.8). Energy expenditure estimated via indirect calorimetry was 163±19 kcal (range 139–205 kcal) during the 25-minute circuit and 184±23 kcal (range 150–233) for the entire 30-minute session. CONCLUSION This study suggests that women performing a 30-minute Curves workout are exercising at an intensity within ACSM guidelines for improving aerobic capacity. Additionally, measured energy expenditure was comparable to published data for other common aerobic (brisk walking) and circuit weight training regimes and should be sufficient to favorably alter energy balance. Supported by the American Council on Exercise.