Validating The Nike+ Sport Kit For Estimating Pace, Distance, And Energy Expenditure During Treadmill Exercise

To validate the accuracy of the Nike+ Wireless Sport Kit to estimate pace (min/km), distance (km), and energy expenditure (EE) (kcal/min) during treadmill walking and running, and for two different sensor configurations. Nine male and 9 female moderately endurance trained volunteers (mean + or - SD age: 28.83 + or - 1.90 y; height: 168.72 + or - 1.86 cm; body mass: 62.19 + or - 2.58 kg; VO2max: 54.36 + or - 1.15 mL/kg/min) completed a) a maximal oxygen consumption test and b) the Nike+ validation protocol comprised of level treadmill walking at 53.6, 80.4, and 107.2 m/min, and level treadmill running at 134.0, 160.8, 187.6, and 214.0 m/min. The Nike+ significantly overestimated pace (P [< or =] 0.034) and distance (P [< or =] 0.005) at walking speeds (53.6 and 80.4 m/min) by 23% and 9%, respectively; and significantly underestimated pace (P [< or =] 0.034) and distance (P [< or =] 0.005) at higher running speeds (160.8, 187.6, and 214.0 m/min) by 6% (pace only - laces), 10% and 15%, respectively.