# Validity of the Enode Sensor and My Jump 3 App for Assessing Countermovement Jump Performance
## 4 Discussion  
The current study reinforces the validity and reliability of both the Enode Sensor and My Jump 3 App as tools for measuring vertical jump heights, establishing them as accessible alternatives to traditional Force Plates. Both the Enode Sensor (mean bias: 2.3 cm; ICC: 0.914; R\({}^{2}\): 0.945; Pearson's r: 0.972; [PERSON]'s rho: 0.977) and My Jump 3 (mean bias: 1.3 cm; ICC: 0.968; R\({}^{2}\): 0.973; Pearson's r: 0.987; [PERSON]'s rho: 0.988) demonstrated strong accuracy relative to that of the Force Plate, with My Jump 3 exhibiting closer agreement, as indicated by its lower bias and higher proportion of explained variance. Consistent with previous research that highlights the utility of CM] assessments for evaluating lower-body power and neuromuscular function in athletes [1; 56], measurements with both devices demonstrated high degrees of correlation with Force Plate measurements, indicating these devices' potentials for accurate performance tracking in sports settings. The reliability analysis revealed that both devices had excellent Intraclass Correlation Coefficients (ICCs), with values of 0.914 for the Enode Sensor and 0.968 for My Jump 3, both statistically significant. High ICC values affirm the stability of these devices for repeated measurements over time, making them feasible for longitudinal monitoring in training contexts [32; 33]. This finding is particularly significant in sports, where practitioners require reliable tools to track performance changes and adjust training loads based on accurate feedback [4]. Moreover, the strong positive relationships observed between each device and the Force Plate, as indicated by [PERSON] and [PERSON] correlation coefficients (r = 0.972-0.988), align with previous studies on the My Jump App's validity for jump height assessment [17; 18; 19; 20; 34; 44]. This high degree of correlation validates the suitability of both the Enode Sensor and My Jump 3 App for assessing jump performance in both controlled and field environments, especially given their cost effectiveness and portability compared to those of conventional Force Plates [14; 19]. The Bland-Altman analysis further revealed that both devices slightly overestimated jump heights compared to those measured using the Force Plate, with mean biases of 2.281 cm and 1.297 cm for the Enode Sensor and My Jump 3, respectively. The My Jump 3 App showed closer agreement with the Force Plate, as evidenced by narrower limits of agreement (My Jump 3: from \(-\)0.014 to 3.048 cm; Enode Sensor: from \(-\)0.281 to 4.84 cm), indicating that My Jump 3 may offer greater precision. This finding aligns with studies that have reported near-perfect agreement between My Jump and Force Plate measurements [17; 57]. The higher precision of My Jump 3 could be advantageous for practitioners who require detailed performance analysis, such as in competitive environments or for elite athlete monitoring [14; 58]. The regression analysis results further substantiate the reliability of these devices. R\({}^{2}\) values of 0.945 for the Enode Sensor and 0.973 for My Jump 3 indicate that a large proportion of the variance in Force Plate measurements can be explained by these alternative tools. These findings echo prior studies that have validated wearable devices and mobile applications for CM] assessment, as they provide an accessible means to collect reliable jump data without the logistical constraints of laboratory settings [15; 19; 29]. The high R\({}^{2}\) values in the regression analyses suggest that both the Enode Sensor and My Jump 3 App can accurately predict jump heights, supporting their potential application across different athletic levels and training contexts. These results underscore the My Jump 3 App's accuracy as a measurement tool for vertical jump heights, suggesting it performs comparably to the Force Plate, which is widely regarded as the gold standard.