Joint and muscle-tendon coordination strategies during submaximal jumping (dataset)

Previous research has demonstrated that humans prioritize minimizing energy wastage during submaximal jumping movements by minimizing countermovement depth. However, physical movement constraints may require altered coordination strategies that rely on changes in muscle contractile mechanics. This study compared submaximal jumping with either a preferred or deep countermovement depth to examine how joint and muscle coordination strategies would be adapted in the deep condition. Three-dimensional motion capture, two force plates, electromyography and ultrasonography were used to examine changes in joint kinetics and kinematics, muscle activation and muscle kinematics for the lateral gastrocnemius and soleus. Results demonstrated that a decrease in ankle joint work during the deep countermovement depth was due increased knee flexion, leading to unfavourably short bi-articular muscle lengths and reduced active fascicle length change during ankle plantar flexion. Therefore, ankle joint work was likely decreased due to reduced fascicle length change and operating position on the force-length relationship. Alternatively, hip joint work was significantly increased as a result of altered muscle activation strategies, likely possible due to a substantially greater activation period compared to plantar flexor muscles during jumping. Therefore, coordination strategies at individual joints may be dependent on time availability, where a short plantar flexor activation time results in dependence on intrinsic muscle properties, while the longer time for contraction of muscles at the hip allows for adjustments to voluntary control.