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Altered countermovement jump force profile and muscle-tendon unit kinematics following combined ballistic training.

ABSTRACT: Combined heavy- and light-load ballistic training is often employed in high-performance sport to improve athletic performance and is accompanied by adaptations in muscle architecture. However, little is known about how training affects muscle-tendon unit (MTU) kinematics during the execution of a sport-specific skill (e.g., jumping), which could improve our understanding of how training improves athletic performance. The aim of this study was to investigate vastus lateralis (VL) MTU kinematics during a countermovement jump (CMJ) following combined ballistic training. Eighteen young, healthy males completed a 10-week program consisting of weightlifting derivatives, plyometrics, and ballistic tasks under a range of loads. Ultrasonography of VL and force plate measurements during a CMJ were taken at baseline, mid-test, and post-test. The training program improved CMJ height by 11 ± 13%. During the CMJ, VL's MTU and series elastic element (SEE) length changes and velocities increased from baseline to post-test, but VL's fascicle length change and velocity did not significantly change. It is speculated that altered lower limb coordination and increased force output of the lower limb muscles during the CMJ allowed more energy to be stored within VL's SEE. This may have contributed to enhanced VL MTU work during the propulsion phase and an improved CMJ performance following combined ballistic training.

SUBMITTER: Hoffman BW

PROVIDER: S-EPMC9544266 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Altered countermovement jump force profile and muscle-tendon unit kinematics following combined ballistic training.

Hoffman Ben W BW Raiteri Brent J BJ Connick Mark J MJ Beckman Emma M EM Macaro Angelo A Kelly Vincent G VG James Lachlan P LP

Scandinavian journal of medicine & science in sports 20220727 10

Combined heavy- and light-load ballistic training is often employed in high-performance sport to improve athletic performance and is accompanied by adaptations in muscle architecture. However, little is known about how training affects muscle-tendon unit (MTU) kinematics during the execution of a sport-specific skill (e.g., jumping), which could improve our understanding of how training improves athletic performance. The aim of this study was to investigate vastus lateralis (VL) MTU kinematics d ...[more]

PMID: 35844051

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Project description:The aim of this study was to identify the acute effects of a differential-learning training program on football kicking performance and countermovement jump. Twenty youth Portuguese under-15 football players participated in this study. All players were exposed to two training approaches: i) traditional, in which the players performed a total of 36 kicks in a blocked and repetitive approach; and ii) differential learning, which consisted in the 36 kicks using differential variations in each kick. Football kicking impact and velocity were assessed using a Stalker radar gun, while the kicking accuracy was assessed by aggregating the total number of points achieved during 12 kicks into a goal, which was divided into quantifiable scoring zones. Lastly, leg power was measured using a countermovement jump. Measurements were performed at baseline, post-intervention, and following a 35-minute training match. The comparisons between the baseline and post-test revealed that the differential learning approach promoted a possibly ~5% increase in the countermovement jump (small effects) and a likely ~3% increase in the average velocity (small effects) when compared with the traditional training approach. From the accuracy perspective, there was a moderate decrease from the baseline to the post-test and post-match in accurate kicks into zone 1 (centre of the goal) and a moderate decrease from the baseline to the post-match in accurate kicks into zone 5 (lateral zones at short height) in the differential intervention. In turn, a small increase in the accurate kicks into zones 4 and 6 (lateral zones of the goal and nearest to the bar, respectively) was found from the baseline to the post-match in the differential intervention. Overall, the differential learning intervention was more beneficial than a traditional training protocol with respect to acute improvements in countermovement jump performance, football kicking velocity and higher scoring zones kicking accuracy.

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Altered countermovement jump force profile and muscle-tendon unit kinematics following combined ballistic training.

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Altered countermovement jump force profile and muscle-tendon unit kinematics following combined ballistic training.

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