ACCURACY OF A WRIST-WORN ACTIVITY MONITOR DURING RESISTANCE TRAINING EXERCISES AT DIFFERENT MOVEMENT SPEEDS

O. Anderson1, A.H.K. Montoye, FACSM2, D. Boss2, J.A. Steeves3, and S.A. Conger1 1Boise State University, Boise, ID;2Alma College, Alma, MI; 3Maryville College, Maryville, TN Speed of movement can affect the accuracy of objective physical activity (PA) monitors. It is likely that speed of movement could affect the accuracy of accelerometer-based PA monitors during other types of exercise. PURPOSE: To assess the ability of the Atlas Wearables Wristband2, an accelerometer-based PA monitor developed specifically for resistance training (RT), to identify the individual RT exercise type and count repetitions during RT exercises at various movement speeds. METHODS: Male and female participants (n=50) aged 18-55 yrs were recruited for this study. Each participant wore an Atlas Wearables Wristband2 on his/her left wrist. Participants completed seven sets of ten repetitions for five different upper/lower body RT exercises (barbell bench press, dumbbell (DB) bent-over row, DB calf raise, DB overhead triceps extension, and DB bicep curl) using a self-selected, light weight. The speed of each set was randomized and completed at a different metronome-paced cadence ranging from a slow cadence of 4 s/rep to a fast cadence of 1 s/rep (sets differed by 0.5 s/rep increments). Percentage of correct activity type identification and repetition counting were calculated. In addition, mean absolute percent error (MAPE) and bias were calculated for repletion counting. One-way ANOVAs were used to compare the actual exercise type/number of repetitions between the seven different speeds. RESULTS: For each exercise, there tended to be significant difference between the slower speeds and the fastest speed for activity type identification and repletion counting (p\u3c0.05). Overall across all exercises, the highest accuracy for activity type identification and repetition counting and the lowest MAPE and bias occurred during the 1.5 s/rep speed (the second fastest speed tested).CONCLUSION: The accuracy of the Atlas Wearables Wristband2 to identify exercise type and count repetitions varied based on the speed of movement during RT exercises. Overall, the exercise type and repetition count accuracy tended to improve as the speed of movement increased up to 1.5 s/rep. The results of this study suggest that researchers using this device should train participants to complete prescribed exercises at specific speeds for the highest accuracy in identifying exercise and counting repetitions during RT exercise