Concurrent Validity of the Optojump Infrared Photocell System in Lower Limb Peak Power Assessment: Comparative Analysis with the Wingate Anaerobic Test and Sprint Performance

Aim: This study analyzed the concurrent validity of the Optojump infrared photocell system for estimating lower limb peak power by comparing it with the 15 s Wingate anaerobic test (WAnT) and examining relationships with sprint performance indicators. Methods: Twelve physically active university students (ten males, two females; age: 23.39 +/- 1.47 years; body mass: 73.08 +/- 9.19 kg; height: 173.67 +/- 6.97 cm; BMI: 24.17 +/- 1.48 kg<middle dot>m(-2)) completed a cross-sectional validation protocol. Participants performed WAnT on a calibrated Monark ergometer (7.5% body weight for males, 5.5% for females), 30 s continuous jump tests using the Optojump system (Microgate, Italy), and 30 m sprint assessments with 10 m and 20 m split times. Peak power was expressed in absolute (W), relative (W<middle dot>kg(-1)), and allometric (W<middle dot>kg(-0.67)) terms. Results: Thirty-second continuous jump testing produced systematically higher peak power values across all metrics (p < 0.001). Mean differences indicated large effect sizes: relative power (Cohen's d = 0.99; 18.263 +/- 4.243 vs. 10.99 +/- 1.58 W<middle dot>kg(-1)), absolute power (d = 0.86; 1381.71 +/- 393.44 vs. 807.28 +/- 175.45 W), and allometric power (d = 0.79). Strong correlations emerged between protocols, with absolute power showing the strongest association (r = 0.842, p < 0.001). Linear regression analysis revealed that 30 s continuous jump-derived measurements explained 71% of the variance in Wingate outcomes (R-2 = 0.710, p < 0.001). Sprint performance showed equivalent predictive capacity for both tests (Wingate: R-2 = 0.66; 30 s continuous jump: R-2 = 0.67). Conclusions: The Optojump infrared photocell system provides a valid and practical alternative to laboratory-based ergometry for assessing lower limb anaerobic power. While it systematically overestimates absolute values compared with the Wingate anaerobic test, its strong concurrent validity (r > 0.80), large effect sizes, and equivalent predictive ability for sprint performance (R-2 = 0.66-0.71) confirm its reliability as a field-based assessment tool. These findings underscore the importance of sport-specific, weight-bearing assessment technologies in modern sports biomechanics, providing coaches, practitioners, and clinicians with a feasible method for monitoring performance, talent identification, and training optimization. The results further suggest that Optojump-based protocols can bridge the gap between laboratory precision and ecological validity, supporting both athletic performance enhancement and injury prevention strategies.