The validity and reliability of a novel mobile app to measure agility performance in the physically active youth population

• Main Authors: Juan A. Escobar Álvarez, Rocío Carrasco-Zahínos, Pedro R. Olivares, Sebastián Feu, Robinson Ramírez-Velez, Miguel Ángel Pérez Sousa
• Format: Article
• Language: English
• Published: Asociación Española de Ciencias del Deporte 2020-12-01
• Series: European Journal of Human Movement
• Subjects: app; agility; validity; reliability
• Online Access: https://www.eurjhm.com/index.php/eurjhm/article/view/569

Agility is a key component of physical fitness in adolescents. However, the measurement of this variable is usually complex, requiring high cost instruments and complex software. To test the validity and reliability of a novel iPhone app (Lap Tracker Auto-timer) to measure agility performance among adolescents. Twenty-four physically active adolescents (15.7 ± 2.3 years old) participated in two testing sessions (separated by 7 days). They performed three 4 x 10 m agility test trials measured by Photocell or the iPhone app. The correlation analysis revealed high validity (r = .92; 95% confidence interval [CI] = .88 – .95), with a standard error of the estimate of 0.56 s (p < 0.001). The coefficient of variation (CV; 0.09) and intraclass correlation coefficient (ICC; .93; 95% CI = .85 – .97) showed an acceptable reliability. This study demonstrated that the iPhone App Lap Tracker Auto-timer could be a valid, reliable and low-cost tool to evaluate agility performance in adolescents. However, more studies are required to guarantee the utility of this app.