Aleksic Jelena, Mesaroš David, Kanevsky Dmitry, Knežević Olivera M, Cabarkapa Dimitrije, Faj Lucija, Mirkov Dragan M
Faculty of Sport and Physical Education, University of Belgrade, 11000 Belgrade, Serbia.
School of Electrical Engineering, University of Belgrade, 11000 Belgrade, Serbia.
Life (Basel). 2024 Dec 11;14(12):1641. doi: 10.3390/life14121641.
The countermovement vertical jump (CMJ) is widely used in sports science and rehabilitation to assess lower body power. In controlled laboratory environments, a complex analysis of CMJ performance is usually carried out using motion capture or force plate systems, providing detailed insights into athlete's movement mechanics. While these systems are highly accurate, they are often costly or limited to laboratory settings, making them impractical for widespread or field use. This study aimed to evaluate the accuracy of MMPose, a markerless 2D pose estimation framework, for CMJ analysis by comparing it with force plates. Twelve healthy participants performed five CMJs, with each jump trial simultaneously recorded using force plates and a smartphone camera. Vertical velocity profiles and key temporal variables, including jump phase durations, maximum jump height, vertical velocity, and take-off velocity, were analyzed and compared between the two systems. The statistical methods included a Bland-Altman analysis, correlation coefficients (r), and effect sizes, with consistency and systematic differences assessed using intraclass correlation coefficients (ICC) and paired samples -tests. The results showed strong agreement (r = 0.992) between the markerless system and force plates, validating MMPose for CMJ analysis. The temporal variables also demonstrated high reliability (ICC > 0.9), with minimal systematic differences and negligible effect sizes for most variables. These findings suggest that the MMPose-based markerless system is a cost-effective and practical alternative for analyzing CMJ performance, particularly in field settings where force plates may be less accessible. This system holds potential for broader applications in sports performance and rehabilitation, enabling more scalable, data-driven movement assessments.
反向纵跳（CMJ）在运动科学和康复领域被广泛用于评估下肢力量。在受控的实验室环境中，通常使用动作捕捉或测力台系统对CMJ表现进行复杂分析，从而深入了解运动员的运动力学。虽然这些系统非常精确，但它们往往成本高昂或仅限于实验室环境使用，这使得它们在广泛应用或现场使用时不切实际。本研究旨在通过将无标记二维姿态估计框架MMPose与测力台进行比较，评估其在CMJ分析中的准确性。12名健康参与者进行了5次CMJ，每次跳跃试验同时使用测力台和智能手机摄像头进行记录。分析并比较了两个系统的垂直速度曲线和关键时间变量，包括跳跃阶段持续时间、最大跳跃高度、垂直速度和起跳速度。统计方法包括Bland-Altman分析、相关系数（r）和效应量，使用组内相关系数（ICC）和配对样本t检验评估一致性和系统差异。结果显示，无标记系统与测力台之间具有高度一致性（r = 0.992），验证了MMPose在CMJ分析中的有效性。时间变量也显示出高可靠性（ICC > 0.9），大多数变量的系统差异最小，效应量可忽略不计。这些发现表明，基于MMPose的无标记系统是分析CMJ表现的一种经济高效且实用的替代方法，特别是在难以使用测力台的现场环境中。该系统在运动表现和康复领域具有更广泛的应用潜力，能够实现更具可扩展性的数据驱动的运动评估。
