Neuromuscular functioning of athletes and non-athletes in the drop jump

1998 ◽  
Vol 78 (5) ◽  
pp. 432-440 ◽  
Author(s):  
Jukka T. Viitasalo ◽  
Aki Salo ◽  
Jukka Lahtinen
Keyword(s):  
Drop Jump ◽  
Neuromuscular Functioning

scholarly journals Biomechanical Symmetry during Drop Jump Landing and Takeoff in Adolescent Athletes Following Recent Anterior Cruciate Ligament Reconstruction

Symmetry ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 639
Author(s):  
Eva M. Ciccodicola ◽  
Nicole M. Mueske ◽  
Mia J. Katzel ◽  
Curtis D. VandenBerg ◽  
James Lee Pace ◽  
...  
Keyword(s):  
Power Generation ◽  
Anterior Cruciate Ligament ◽  
Anterior Cruciate Ligament Reconstruction ◽  
Ligament Reconstruction ◽  
Cruciate Ligament ◽  
Jump Height ◽  
Drop Jump ◽  
Adolescent Athletes ◽  
Cruciate Ligament Reconstruction ◽  
Anterior Cruciate

This study investigated asymmetry between lower extremities during the landing and takeoff phases of a vertical drop jump (VDJ) in adolescent athletes following anterior cruciate ligament reconstruction (ACLR) and examined if performance was affected by reducing jump height. Thirty-three athletes who underwent ACLR and were referred for 3D biomechanical assessment before returning to play (mean age 15.9, SD 1.3 years; 16/33 female; mean time since surgery 7.4, SD 1.2 months) completed the VDJ while kinematics and kinetics were collected using motion capture. Lower extremity symmetry was compared between phases using paired t-tests. Jump height was calculated to measure performance. Asymmetries in ankle inversion, ankle adduction, knee adduction, hip adduction, hip adduction moment, and hip rotation moment were observed in both phases. Asymmetry was also observed in both phases for sagittal moments and power integrals at the knee and ankle and total power integral, with the magnitude of asymmetry being smaller during takeoff for power absorption/generation. Jump height was related to power generation integrals during takeoff but not to the asymmetry of power generation. Since asymmetries are translated from landing through takeoff, rehabilitation should address both phases to decrease injury risk and maximize performance after return to play.

scholarly journals Change of Direction Deficit in National Team Rugby Union Players: Is There an Influence of Playing Position?

Sports ◽  
2018 ◽  
Vol 7 (1) ◽  
pp. 2 ◽  
Author(s):  
Tomás Freitas ◽  
Pedro Alcaraz ◽  
Chris Bishop ◽  
Julio Calleja-González ◽  
Ademir Arruda ◽  
...  
Keyword(s):  
Rugby Union ◽  
Drop Jump ◽  
Repetition Maximum ◽  
Change Of Direction ◽  
National Team ◽  
Standing Long Jump ◽  
Long Jump ◽  
Median Split ◽  
Rugby Players

The aim of this study was to investigate the change of direction (COD) ability and deficits of elite rugby union players, discriminating between position (backs and forwards), and between “faster and slower players”, in multiple COD tasks. Twenty-four male rugby union players from the Brazilian senior National team completed the following assessments: Squat and countermovement jumps; drop jump; standing long jump, horizontal triple jumps; 40-m linear sprint; Pro-agility, L-Drill, and Zig-zag COD tests; and squat 1-repetition maximum. The differences between backs and forwards and between faster and slower performers were examined using magnitude-based inferences. Backs were faster (in both linear and COD speed tests) and jumped higher than forwards. Moreover, they generated an inferior sprint momentum. No differences were found in COD deficit between playing positions. However, when dividing the sample by median split, faster players outperformed their slower counterparts in all power–speed variables and presented higher COD deficits. These results suggest that separating rugby players by playing position might not discriminate players with different COD skills and that the median split analysis is more sensitive to identifying these differences. Furthermore, the present data indicate that faster rugby players are less efficient at changing direction and tolerating higher approach velocities in COD maneuvers.

scholarly journals SÉRIES MÚLTIPLAS DE SQUAT JUMP AUMENTAM O SALTO VERTICAL DE SALTADORES DE ELITE NO ATLETISMO?

2018 ◽  
Vol 26 (1) ◽  
pp. 39
Author(s):  
Tulio Alfano Moura ◽  
Leonardo Dos Santos Oliveira ◽  
Robson Furlan Ricardo ◽  
Marcelo Alves Costa ◽  
Victor Hugo Alves Okazaki
Keyword(s):  
Drop Jump ◽  
Squat Jump

Em provas do atletismo que requerem potência muscular, há uma maior tendência de utilização de fibras do tipo II. Desta forma, exercícios de força como atividade condicionante podem acarretar em melhora no processo de contração muscular e no desempenho da atividade seguinte. Portanto, o objetivo do estudo foi analisar o efeito de diferentes atividades condicionantes na altura de salto vertical em atletas de provas de salto no atletismo. Doze atletas de elite do atletismo brasileiro (7 homens e 5 mulheres; 16 a 27 anos), em início de temporada esportiva, realizaram um teste de salto vertical com contra-movimento. Os testes foram realizados após três condições em dias distintos, a saber: I) Sem Atividade Condicionante (Controle), II) Squat Jump com 80% da massa corporal e III) Drop Jump de uma altura de 40cm. Foram realizados três saltos verticais após cada atividade condicionante. Adotou-se um intervalo de três minutos entre a realização da atividade condicionante e salto vertical e de um minuto entre cada tentativa de salto vertical. Foi demonstrado efeito do fator atividade condicionante para a altura de salto vertical, F(11, 22) = 9,69; P < 0,001. A condição Squat Jump apresentou maior altura do salto vertical quando comparada à condição controle (P = 0,003; ?2 = 0,64). Em contrapartida, não foi encontrado aumento do salto vertical na condição Drop Jump quando comparada à condição controle (P = 0,99). O número de saltos e o limitado controle da técnica utilizada durante a realização do Drop Jump podem ter influenciado o desempenho do salto vertical. Desta forma, o aparecimento da potencialização pós-ativação está condicionado à intensidade e à natureza da atividade condicionante. Por conseguinte, sugerimos que a realização de Squat Jump pode ser benéfica para o desempenho de atletas de modalidades de potência.

scholarly journals Machine Learning-Based Estimation of Ground Reaction Forces and Knee Joint Kinetics from Inertial Sensors While Performing a Vertical Drop Jump

Sensors ◽  
2021 ◽  
Vol 21 (22) ◽  
pp. 7709
Author(s):  
Serena Cerfoglio ◽  
Manuela Galli ◽  
Marco Tarabini ◽  
Filippo Bertozzi ◽  
Chiarella Sforza ◽  
...  
Keyword(s):  
Neural Network ◽  
Machine Learning ◽  
Knee Joint ◽  
Field Analysis ◽  
Ground Reaction Forces ◽  
Drop Jump ◽  
Joint Moments ◽  
Data Set ◽  
Joint Kinetics ◽  
Reaction Forces

Nowadays, the use of wearable inertial-based systems together with machine learning methods opens new pathways to assess athletes’ performance. In this paper, we developed a neural network-based approach for the estimation of the Ground Reaction Forces (GRFs) and the three-dimensional knee joint moments during the first landing phase of the Vertical Drop Jump. Data were simultaneously recorded from three commercial inertial units and an optoelectronic system during the execution of 112 jumps performed by 11 healthy participants. Data were processed and sorted to obtain a time-matched dataset, and a non-linear autoregressive with external input neural network was implemented in Matlab. The network was trained through a train-test split technique, and performance was evaluated in terms of Root Mean Square Error (RMSE). The network was able to estimate the time course of GRFs and joint moments with a mean RMSE of 0.02 N/kg and 0.04 N·m/kg, respectively. Despite the comparatively restricted data set and slight boundary errors, the results supported the use of the developed method to estimate joint kinetics, opening a new perspective for the development of an in-field analysis method.

scholarly journals Biomechanical Symmetry During Drop Jump Landing And Takeoff In Adolescent Athletes Following Recent ACL Reconstruction

2021 ◽  
Vol 53 (8S) ◽  
pp. 142-143
Author(s):  
Tracy Zaslow ◽  
Eva Ciccodicola ◽  
Nicole Mueske ◽  
Mia Katzel ◽  
Curtis Vandenberg ◽  
...  
Keyword(s):  
Acl Reconstruction ◽  
Drop Jump ◽  
Adolescent Athletes ◽  
Jump Landing
Sign in / Sign up

Export Citation Format

Share Document