Biomechanical Comparison in Different Jumping Tasks Between Untrained Boys and Men

Abstract

This study examines the biomechanical differences during different vertical jump tasks in 12 prepubescent and 12 adult males. The sagittal knee kinematics, vertical ground reaction force (vGRF) and electromyographic (EMG) activity of 5 lower extremity muscles were recorded. Compared with boys, men presented higher peak vGRF during the propulsive phase in all examined jumps, but lower values during the braking phase, even when related to body mass. Normalized EMG agonist activity in all phases was higher in men (p < .05), while antagonist coactivation was enhanced in boys (p < .05). The knee joint was on average 9 degrees more flexed at touchdown in men during drop jump tasks, but boys exhibited 12 degrees and 17 degrees higher knee flexion at the deepest point when performing drop jump from 20 and 40 cm, respectively. In conclusion, the performance deficit observed in boys in all jump types is a reflection of their immature technique, which could be partly attributed to the less efficient stiffness regulation and activation of their neuromuscular system.

Consistency of Field-Based Measures of Neuromuscular Control Using Force-Plate Diagnostics in Elite Male Youth Soccer Players

“…Conversely, younger children appear to land with greater knee and hip extension, which combined with heightened muscle co-contraction upon impact, will lead to higher pVGRF (9, 48). Supporting this notion, lower pVGRF related to body mass during the breaking phase of a DVJ have been reported in adults versus boys (25). This may be due to more efficient stretch reflex utilization and greater levels of muscle activation prior to landing and during the breaking phase of the jump (24).…”

“…In order to accurately assess neuromuscular control in male youth soccer players, there is a need for reliable and valid testing protocols (41). Currently in youth males, the most common mode of assessment is measurement of landing forces during a drop vertical jump (DVJ) (24, 25, 40). This protocol has shown strong reliability in male and female high school athletes (ICC range = 0.89 – 0.98) (40).…”

Is There a Progressive Withdrawal of Physiological Protections against High-Intensity Exercise-Induced Fatigue during Puberty?

“…Conversely, O'Brien et al [42] reported higher co-activation levels in adults compared to children, which seems consistent with the greater force production capacity in adults. Finally, higher co-activation levels have been observed in children during poly-articular movements such as walking [53] and jumping [54,55].…”

Cold-water immersion alters muscle recruitment and balance of basketball players during vertical jump landing

“…It is often related to injuries in basketball, either by stepping on the foot of another player or by any type of imbalance (Mckay, Goldie, Payne, & Cakes, 2001). Several studies have evaluated the landing after the jump (Lazaridis et al, 2013;Nyland et al, 2011;Oliver & Smith, 2010;Ruan & Li, 2010;Un et al, 2013;Ziv & Lidor, 2010) as well as the effect of cooling on electromyographic (EMG) activity and balance oscillation (Fischer, Van Lunen, Branch, & Pirone, 2009), however, the results are still divergent. Schmid, Moffat, and Gutierrez (2010) and Wang, Toner, Lemonda, and Zohar (2010) observed reductions in unipodal vertical jump performance after the use of cryotherapy (with a crushed-ice bag and cold-water immersion, respectively).…”