Timing differences in the generation of ground reaction forces between the initial and secondary landing phases of the drop vertical jump

Aim: The purpose of this study was to quantify ground reaction forces for some of the most commonly utilised volleyball blocking approaches and to examine their kinetic and kinematic characteristics. Basic procedures: The study was comprised of 18 healthy recreationally active women who volunteered to participate. Immediately after completion of the warm-up protocol, subjects performed 5 blocking approaches: stationary blocking approach (SBA), shuffle block to the right (SHBR), shuffle block to the left (SHBL), swing block to the right (SWBR) and swing block to the left (SWBL). In order to allow adequate recovery, each trial was randomly assigned and separated by a 1-2 minute rest interval. A uni-axial force plate with data acquisition system sampling at 1000 Hz was used to measure ground reaction forces. Main findings: SWBR and SWBL unveiled the greatest peak concentric force and rate of force development when compared to SBA, while no difference was observed when compared to SHBR and SHBL. Results: No significant differences were observed in peak landing force, impulse, and vertical jump height between any of the blocking approaches examined in this study. Conclusions: Knowing biomechanical characteristics of some of the most commonly utilised volleyball blocking approaches may help athletes to appropriately respond and quickly adjust to the opponent’s attacking position. Kinetic and kinematic variables are likely to be augmented with an advanced level of competition and can be trained and improved by properly designed and implemented strength and conditioning programmes.

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Landing Constraints Influence Ground Reaction Forces and Lower Extremity EMG in Female Volleyball Players

Journal of Applied Biomechanics ◽

10.1123/jab.20.1.38 ◽

2004 ◽

Vol 20 (1) ◽

pp. 38-50 ◽

Cited By ~ 20

Author(s):

Mark D. Tillman ◽

Rachel M. Criss ◽

Denis Brunt ◽

Chris J. Hass

Keyword(s):

Muscle Activity ◽

Repeated Measures ◽

Muscle Activation ◽

Vertical Jump ◽

Lateral Loading ◽

Initial Contact ◽

Ground Reaction Forces ◽

Vertical Loading ◽

Volleyball Players ◽

Reaction Forces

The purposes of this study were to analyze double-limb, dominant-limb, and nondominant-limb landings, each with a two-footed takeoff, in order to detect potential differences in muscle activity and ground reaction forces and to examine the possible influence of leg dominance on these parameters. Each of the three jump landing combinations was analyzed in 11 healthy female volleyball players (age 21 ± 3 yrs; height 171 ± 5 cm, mass 61.6 ± 5.5 kg, max. vertical jump height 28 ± 4 cm). Ground reaction forces under each limb and bilateral muscle activity of the vastus medialis, hamstrings, and lateral gastrocnemius muscles were synchronized and collected at 1,000 Hz. Normalized EMG amplitude and force platform data were averaged over five trials for each participant and analyzed using repeated-measures ANOVA. During the takeoff phase in jumps with one-footed landings, the non-landing limb loaded more than the landing limb (p= 0.003). During the 100 ms prior to initial contact, single-footed landings generated higher EMG values than two-footed landings (p= 0.004). One-footed landings resulted in higher peak vertical loading, lateral loading, and rate of lateral loading than two-footed landings (p< 0.05). Trends were observed indicating that muscle activation during one-footed landings is greater than for two-footed landings (p= 0.053 vs.p= 0.077). The greater forces and rate of loading produced during single-limb landings implies a higher predisposition to injury. It appears that strategic planning and training of jumps in volleyball and other jumping sports is critical.

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Characterization of Multiple Movement Strategies in Participants With Chronic Ankle Instability

Journal of Athletic Training ◽

10.4085/1062-6050-480-17 ◽

2019 ◽

Vol 54 (6) ◽

pp. 698-707 ◽

Cited By ~ 1

Author(s):

J. Ty Hopkins ◽

S. Jun Son ◽

Hyunsoo Kim ◽

Garritt Page ◽

Matthew K. Seeley

Keyword(s):

Sagittal Plane ◽

Ankle Instability ◽

Vertical Jump ◽

Frontal Plane ◽

Chronic Ankle Instability ◽

Control Group ◽

Ground Reaction Forces ◽

Sensorimotor Deficits ◽

Movement Strategies ◽

Reaction Forces

Context Chronic ankle instability (CAI) is characterized by multiple sensorimotor deficits, affecting strength, postural control, motion, and movement. Identifying specific deficits is the key to developing appropriate interventions for this patient population; however, multiple movement strategies within this population may limit the ability to identify specific movement deficits. Objective To identify specific movement strategies in a large sample of participants with CAI and to characterize each strategy relative to a sample of uninjured control participants. Design Descriptive laboratory study. Setting Biomechanics laboratory. Patients or Other Participants A total of 200 individuals with CAI (104 men, 96 women; age = 22.3 ± 2.2 years, height = 174.2 ± 9.5 cm, mass = 72.0 ± 14.0 kg) were selected according to the inclusion criteria established by the International Ankle Consortium and were fit into clusters based on movement strategy. A total of 100 healthy individuals serving as controls (54 men, 46 women; age = 22.2 ± 3.0 years, height = 173.2 ± 9.2 cm, mass = 70.7 ± 13.4 kg) were compared with each cluster. Main Outcome Measure(s) Lower extremity joint biomechanics and ground reaction forces were collected during a maximal vertical jump landing, followed immediately by a side cut. Data were reduced to functional output or curves, kinematic data from the frontal and sagittal planes were reduced to a single representative curve for each plane, and representative curves were clustered using a Bayesian clustering technique. Estimated functions for each dependent variable were compared with estimated functions from the control group to describe each cluster. Results Six distinct clusters were identified from the frontal-plane and sagittal-plane data. Differences in joint angles, joint moments, and ground reaction forces between clusters and the control group were also identified. Conclusions The participants with CAI demonstrated 6 distinct movement strategies, indicating that CAI could be characterized by multiple distinct movement alterations. Clinicians should carefully evaluate patients with CAI for sensorimotor deficits and quality of movement to determine the appropriate interventions for treatment.

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The Effects of Cryotherapy on Ground-Reaction Forces Produced during a Functional Task

Journal of Sport Rehabilitation ◽

10.1123/jsr.9.1.3 ◽

2000 ◽

Vol 9 (1) ◽

pp. 3-14 ◽

Cited By ~ 15

Author(s):

Stephen J. Kinzey ◽

Mitchell L. Cordova ◽

Kevin J. Gallen ◽

Jason C. Smith ◽

Justin B. Moore

Keyword(s):

Outcome Measures ◽

Ground Reaction Force ◽

Repeated Measures ◽

Vertical Jump ◽

Weight Bearing ◽

Reaction Force ◽

Ground Reaction Forces ◽

Vertical Ground Reaction Force ◽

Reaction Forces ◽

Vertical Ground

Objective:To determine whether a standard 20-min ice-bath (10°C) immersion of the leg alters vertical ground-reaction-force components during a 1 -legged vertical jump.Design:A 1 × 5 factorial repeated-measures model was used.Setting:The Applied Biomechanics Laboratory at The University of Mississippi.Participants:Fifteen healthy and physically active subjects (age = 22.3 ± 2.1 years, height = 177.3 ± 12.2 cm, mass = 76.3 ± 19.1 kg) participated.Intervention:Subjects performed 25 one-legged vertical jumps with their preferred extremity before (5 jumps) and after (20 jumps) a 20-min cold whirlpool to the leg. The 25 jumps were reduced into 5 sets of average trials.Main Outcome Measures:Normalized peak and average vertical ground-reaction forces, as well as vertical impulse obtained using an instrumented force platform.Results:Immediately after cryotherapy (sets 2 and 3), vertical impulse decreased (P= .01); peak vertical ground-reaction force increased (set 2) but then decreased toward baseline measures (P= .02). Average vertical ground-reaction force remained unchanged (P>.05).Conclusions:The authors advocate waiting approximately 15 min before engaging in activities that require the production of weight-bearing explosive strength or power.

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The Effects Of Lower Body Fatigue On Vertical Jump Ground Reaction Forces

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000519625.43784.36 ◽

2017 ◽

Vol 49 (5S) ◽

pp. 962

Author(s):

Christina N. Cooper ◽

Nicole M. Sauls ◽

Judith Davis ◽

Jasmine Wimbish ◽

Ashley Vazquez ◽

...

Keyword(s):

Vertical Jump ◽

Ground Reaction Forces ◽

Lower Body ◽

Reaction Forces

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An artificial neural network method for predicting three-dimensional lower limb joint moments during vertical jump from measured ground reaction forces

Journal of Biomechanics ◽

10.1016/s0021-9290(06)83695-x ◽

2006 ◽

Vol 39 ◽

pp. S193

Author(s):

T.-W. Lu ◽

S.-M. Shih ◽

Y. Liu ◽

W.-C. Hsu

Keyword(s):

Neural Network ◽

Artificial Neural Network ◽

Lower Limb ◽

Vertical Jump ◽

Three Dimensional ◽

Ground Reaction Forces ◽

Joint Moments ◽

Network Method ◽

Artificial Neural Network Method ◽

Reaction Forces

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Center of Pressure, Vertical Ground Reaction Forces, and Neuromuscular Responses of Special-Forces Soldiers to 43-km Load Carriage in the Field

Journal of Applied Biomechanics ◽

10.1123/jab.2019-0283 ◽

2020 ◽

Vol 36 (5) ◽

pp. 307-312

Author(s):

James Scales ◽

Jamie M. O’Driscoll ◽

Damian Coleman ◽

Dimitrios Giannoglou ◽

Ioannis Gkougkoulis ◽

...

Keyword(s):

Body Weight ◽

Injury Risk ◽

Center Of Pressure ◽

Vertical Jump ◽

Load Carriage ◽

Ground Reaction Forces ◽

Increased Risk ◽

Heel Contact ◽

Before And After ◽

Reaction Forces

The primary purpose of this study was to examine lateral deviations in center of pressure as a result of an extreme-duration load carriage task, with particular focus on heel contact. A total of 20 (n = 17 males and n = 3 females) soldiers from a special operation forces unit (body mass 80.72 [21.49] kg, stature 178.25 [8.75] cm, age 26 [9] y) underwent gait plantar pressure assessment and vertical jump testing before and after a 43-km load carriage event (duration 817.02 [32.66] min) carrying a total external load of 29.80 (1.05) kg. Vertical jump height decreased by 18.62% (16.85%) from 0.30 (0.08) to 0.24 (0.07) m, P < .001. Loading peak and midstance force minimum were significantly increased after load carriage (2.59 [0.51] vs 2.81 [0.61] body weight, P = .035, Glass delta = 0.44 and 1.28 [0.40] vs 1.46 [0.41] body weight, P = .015, Glass delta = 0.45, respectively) and increases in lateral center of pressure displacement were observed as a result of the load carriage task 14.64 (3.62) to 16.97 (3.94) mm, P < .029. In conclusion, load carriage instigated a decrease in neuromuscular function alongside increases in ground reaction forces associated with injury risk and center of pressure changes associated with ankle sprain risk. Practitioners should consider that possible reductions in ankle stability remain once load carriage has been completed, suggesting soldiers are still at increased risk of injury even once the load has been removed.

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Lower-Limb Power cannot be Estimated Accurately from Vertical Jump Tests

Journal of Human Kinetics ◽

10.2478/hukin-2013-0040 ◽

2013 ◽

Vol 38 ◽

pp. 5-13 ◽

Cited By ~ 4

Author(s):

Jean-François Tessier ◽

Fabien-A Basset ◽

Martin Simoneau ◽

Normand Teasdale

Keyword(s):

Lower Limb ◽

Vertical Jump ◽

Ground Reaction Forces ◽

Trained Group ◽

Countermovement Jump ◽

Predictive Equations ◽

Jump Test ◽

Minimal Difference ◽

Reaction Forces ◽

Study Power

Abstract The countermovement jump test is often adopted to monitor lower-limb power of an individual. Despite several studies on the validity of this test, there is still a need to determine the minimal difference needed to be confident that a difference in power between two individuals is present or that a true change in the performance of an individual has occurred. In this study, power was measured from ground reaction forces and compared to that obtained from predictive equations for two groups of subjects (67 trained and 20 highly trained individuals). The height of each jump was determined with kinematic techniques. The main outcome is a large discrepancy between power calculated from ground reaction forces and that calculated from predictive equations. For the trained group, the R-square value between power and predicted power was 0.53 and the minimal difference to consider that two individuals were different was 821.7 W. For the highly trained individuals, a much larger R-square value was obtained (0.94). Despite this, the minimal difference to consider that two individuals were different was still large (689.3 W). The large minimal differences obtained raise serious concerns about using countermovement jumps for appraisal and monitoring of lower-limb power of an individual.

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