Ankle bracing's effects on lower extremity iEMG activity, force production, and jump height during a Vertical Jump Test: An exploratory study

Context:Potential biomechanical compensations allowing for maintenance of maximal explosive performance during prolonged intermittent exercise, with respect to the corresponding rise in injury rates during the later stages of exercise or competition, are relatively unknown.Objective:To identify lower-extremity countermovement-jump (CMJ) biomechanical factors using a principal-components approach and then examine how these factors changed during a 90-min intermittent-exercise protocol (IEP) while maintaining maximal jump height.Design:Mixed-model design.Setting:Laboratory.Participants:Fifty-nine intermittent-sport athletes (30 male, 29 female) participated in experimental and control conditions.Interventions:Before and after a dynamic warm-up and every 15 min during the 1st and 2nd halves of an individually prescribed 90-min IEP, participants were assessed on rating of perceived exertion, sprint/cut speed, and 3-dimensional CMJ biomechanics (experimental). On a separate day, the same measures were obtained every 15 min during 90 min of quiet rest (control).Main Outcome Measures:Univariate piecewise growth models analyzed progressive changes in CMJ performance and biomechanical factors extracted from a principal-components analysis of the individual biomechanical dependent variables.Results:While CMJ height was maintained during the 1st and 2nd halves, the body descended less and knee kinetic and energetic magnitudes decreased as the IEP progressed.Conclusions:The results indicate that vertical-jump performance is maintained along with progressive biomechanical changes commonly associated with decreased performance. A better understanding of lower-extremity biomechanics during explosive actions in response to IEP allows us to further develop and individualize performance training programs.

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Impact of Official Matches on Soccer Referees’ Power Performance

Journal of Human Kinetics ◽

10.1515/hukin-2017-0116 ◽

2018 ◽

Vol 61 (1) ◽

pp. 131-140

Author(s):

Daniel Castillo ◽

Javier Yanci ◽

Jesús Cámara

Keyword(s):

Lower Limb ◽

Vertical Jump ◽

Force Production ◽

Maximum Force ◽

Half Time ◽

Power Performance ◽

Jump Performance ◽

Flight Phase ◽

Jump Test ◽

Time To Stabilization

Abstract The evaluation of match officials’ neuromuscular performance is now an important consideration and the vertical jump test is considered suitable for assessing lower limb power, partly because it is directly related to refereeing. The aim of this study, therefore, was to determine the effect of soccer matches on match officials’ vertical jump performance by assessing various biomechanical variables. Eighteen field referees (FRs) and 36 assistant referees (ARs) who officiated in 18 official matches participated in this study. Before the match, at half time and immediately after the match, officials performed two countermovement jumps. Flight phase time (FT), maximum force production (MFpropulsion), time to production of maximum force (TMFpropulsion), production of maximum power (MP), maximum landing force (MFlanding) and time to stabilization (TTS) were calculated for all jumps. There was a tendency for match officials’ jumping performance to improve after matches than beforehand (FR: effect size (ES) = 0.19 ± 0.36, possibly trivial; AR: ES = 0.07 ± 0.17, likely trivial). There were also likely small and very likely moderate differences between FRs’ MP in pre-match and half-time jumps (ES = 0.46 ± 0.47) and in their pre- and post-match jumps (ES = 0.71 ± 0.48). These results indicate that refereeing soccer matches does not reduce vertical jump performance; the subsequent neuromuscular fatigue is not sufficient to affect landing technique.

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Difference in vertical jumping abilities, endurance and quickness of regeneration lower extremity muscle groups after physical effort between CrossFit and climbing athletes

Polish Journal of Public Health ◽

10.1515/pjph-2017-0036 ◽

2017 ◽

Vol 127 (4) ◽

pp. 168-172

Author(s):

Piotr Gawda ◽

Michał Ginszt ◽

Jakub Smołka ◽

Michał Paćko ◽

Maria Skublewska-Paszkowska ◽

...

Keyword(s):

Lower Extremity ◽

Vertical Jump ◽

Gluteus Maximus ◽

Myoelectric Activity ◽

High Intensity Training ◽

Lower Extremity Muscle ◽

Sport Climbing ◽

Jump Test ◽

Vertical Jumping ◽

Significant Difference

Abstract Introduction. Productive sporting performance in various sports disciplines often heavily depends on jumping abilities as well as on lower limb muscles power and endurance of the athletes involved. Both CrossFit, a popular high-intensity training program and sport climbing require lower extremity muscular power and endurance. Aim. The aim of this study was to compare vertical jumping abilities, endurance and quickness of the regeneration in gastrocnemius lateralis (GL), vastus medialis (VMO) and gluteus maximus (GM) muscles in CrossFit athletes and sport climbers. Material and methods. The study comprised 20 male athletes aged 24.3±4.7, divided into two equal groups: training CrossFit (CF) and sport climbers (SC). Vertical jump test was recorded by Vicon® motion capture system and AMTI® biomechanics force platforms. The myoelectric activity of the GL, VMO and GM muscles was recorded by myon®. Results. Significant difference in height of vertical jump in CrossFit athletes and sport climbers was observed (SC: 125.43 cm, 120.92 cm; CF: 110.42 cm, 110.86 cm; p<0.05). The endurance of the GL muscles in athletes using CrossFit training is significantly higher in comparison to sport climbers. Athletes training CrossFit have a better ability to recover GL, GM and VMO muscles than sport climbers. Conclusions. Sport climbers have better results in vertical jump tests than the athletes doing CrossFit. The endurance of the GL muscles in athletes doing CrossFit is higher in comparison to sport climbers. Athletes doing CrossFit have also better ability to muscles recover than sport climbers.

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Association Between Body Composition and Vertical Jump Performance in Female Collegiate Volleyball Athletes

International Journal of Kinesiology and Sports Science ◽

10.7575/aiac.ijkss.v.9n.4p.43 ◽

2021 ◽

Vol 9 (4) ◽

pp. 43

Author(s):

Lindsey Legg ◽

Megan Rush ◽

Jordan Rush ◽

Stephanie McCoy ◽

John C Garner ◽

...

Keyword(s):

Body Composition ◽

Lower Extremity ◽

Fat Mass ◽

Lean Mass ◽

Gold Standard ◽

Vertical Jump ◽

Jump Height ◽

Fat Percentage ◽

Jump Performance ◽

Total Body

Background of Study: Associations between measures of body composition and vertical jump height have previously been established using a range of instrumentation and prediction equations. Limited data has presented using gold standard measurements for both variables Objective: This investigation sought to examination the relationship between total body and lower extremity measures of body composition and vertical jump performance using gold standard measurements within an athletic population. Methods: Using a cross-sectional, correlational research design fourteen collegiate female volleyball athletes completed body composition, three countermovement jumps (CMJ) and three squat jumps (SJ) analysis using DXA and force platforms. Results: High to very high positive relationships were seen between total body lean (p < 0.001) and fat mass (p < 0.05), lower extremity lean and fat mass (p < 0.01), and CMJ force and power. High negative relationships were present between total body fat percentage(p < 0.05), total fat mass (p < 0.01) and CMJ jump height. Relationships between all body composition variables and SJ performance tended to be weaker, with the exception of total body lean mass (p < 0.05), lower extremity lean mass, and power output (p < 0.01). Conclusions: These findings support much of the previous literature in that increases of mass have subsequent increases in force and power production; however caution should be taken will increases in mass coming from fat or lean tissue.

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Relationship Between Maximum Strength and Vertical Jump Performance in Junior Speed Skaters

GYMNASIUM ◽

10.29081/gsjesh.2020.21.2.10 ◽

2020 ◽

Vol XXI (2) ◽

pp. 140

Author(s):

Raluca Doina Ștef ◽

Emilia Florina Grosu

Keyword(s):

Intervention Program ◽

Isometric Force ◽

Vertical Jump ◽

Jump Height ◽

Countermovement Jump ◽

Post Intervention ◽

Jump Performance ◽

Squat Jump ◽

Jump Test ◽

Maximal Isometric Force

The aim of this study was to determine the relationships between back squat maximal strength, maximal isometric force, jump squat and countermovement jump and whether power training improves parameters mentioned above in well-trained speed skaters. Sixteen athletes devided in two groups, performed two maximal squat strength test and two vertical jump test before and after the intervention program. Absolute strength showed a strong correlation with squat jump height (r = 0.762, p < 0.001) and countermovement jump height (r = 0.760, p < 0.001) but also between maximal isometric force and squat jump (r = 0.418, p = 0.036). Percentage change within the experiment group were significantly different from pre to post intervention for each parameter tested in the order described, respectively: 14%; 16.8%; 14.9%; 9.1%. These results suggest that jump squat training can improve several athletic performances developing high levels of lower body strength to enhance jump performance.

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Ankle Bracing Decreases Vertical Jump Height and Alters Lower Extremity Kinematics

International Journal of Athletic Therapy & Training ◽

10.1123/ijatt.2014-0143 ◽

2016 ◽

Vol 21 (2) ◽

pp. 39-46 ◽

Cited By ~ 3

Author(s):

Bradley Smith ◽

Tina Claiborne ◽

Victor Liberi

Keyword(s):

Lower Extremity ◽

Vertical Jump ◽

Plantar Flexion ◽

Emg Activity ◽

Jump Height ◽

Jump Performance ◽

Vertical Jump Height ◽

Hip Flexion ◽

Ankle Plantar Flexion ◽

Ankle Bracing

The purpose of this study was to determine the effects of ankle bracing on vertical jump performance and lower extremity kinematics and electromyography (EMG) activity. Twenty healthy college athletes participated in two sessions, separated by a minimum of 24 hr. They performed five jumps with no brace on the first day, and five jumps with both ankles braced on the second day. An average of the three highest jumps each day was used for analysis. Braced vertical jump performance significantly decreased (p = .002) as compared with the unbraced condition. In addition, hip flexion (p = .043) and ankle plantar flexion (p = .001) angles were significantly smaller during the braced vertical jump. There was also a significant reduction in soleus muscle EMG (p = .002) during the braced condition.

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Lower Extremity Strength and Coordination Are Independent Contributors to Maximum Vertical Jump Height

Journal of Applied Biomechanics ◽

10.1123/jab.17.3.181 ◽

2001 ◽

Vol 17 (3) ◽

pp. 181-187 ◽

Cited By ~ 20

Author(s):

Masao Tomioka ◽

Tammy M. Owings ◽

Mark D. Grabiner

Keyword(s):

Older Adults ◽

Muscle Strength ◽

Lower Extremity ◽

Relative Phase ◽

Vertical Jump ◽

Knee Extension ◽

Jump Height ◽

Knee Extension Strength ◽

Vertical Jump Height ◽

Lower Extremity Strength

We previously reported that lower extremity muscular strength of older adults did not predict success of a balance recovery task. We propose that lower extremity coordination may limit performance independently of lower extremity strength. The present study was conducted to determine the extent to which knee extension strength and hip–knee coordination independently contribute to maximum vertical jump height. Maximum vertical jump height and isometric and isokinetic knee extension strength and power were determined in 13 young adults. Hip–knee coordination during the vertical jump was quantified using relative phase angles. Stepwise nonlinear multiple regression determined the variable set that best modeled the relationship between the dependent variable, maximum vertical jump height, and the independent variables of strength, power, and coordination. The quadratic terms of the normalized knee extension strength at 60 deg·s–1, and the average relative phase during the propulsion phase of the vertical jump, collectively accounted for more than 80% of the shared variance (p= .001). The standardized regression coefficients of the two terms, .59 and .52, respectively (p= .004 and .008), indicated the independence and significance of the contributions of knee extension strength and hip–knee coordination to maximum vertical jump height. Despite the pitfalls of extrapolating these results to older adults performing a balance recovery task, the results are interpreted as supporting the contention that while muscle strength confers a number of functional benefits, the ability to avoid falling as a result of a trip is not necessarily ensured. Increased muscle strength per se can occur in the absence of improved kinematic coordination.

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Effects of Neuromuscular Strength Training on Vertical Jumping Performance— A Computer Simulation Study

Journal of Applied Biomechanics ◽

10.1123/jab.17.2.113 ◽

2001 ◽

Vol 17 (2) ◽

pp. 113-128 ◽

Cited By ~ 60

Author(s):

Akinori Nagano ◽

Karin G.M. Gerritsen

Keyword(s):

Lower Extremity ◽

Strength Training ◽

Muscle Force ◽

Vertical Jump ◽

Jump Height ◽

Jumping Performance ◽

Vertical Jump Height ◽

Muscle Groups ◽

Isometric Muscle ◽

Isometric Muscle Force

The purpose of this study was twofold: (a) to systematically investigate the effect of altering specific neuromuscular parameters on maximum vertical jump height, and (b) to systematically investigate the effect of strengthening specific muscle groups on maximum vertical jump height. A two-dimensional musculoskeletal model which consisted of four rigid segments, three joints, and six Hill-type muscle models, representing the six major muscles and muscle groups in the lower extremity that contribute to jumping performance, was trained systematically. Maximum isometric muscle force, maximum muscle shortening velocity, and maximum muscle activation, which were manipulated to simulate the effects of strength training, all had substantial effects on jumping performance. Part of the increase in jumping performance could be explained solely by the interaction between the three neuromuscular parameters. It appeared that the most effective way to improve jumping performance was to train the knee extensors among all lower extremity muscles. For the model to fully benefit from any training effects of the neuromuscular system, it was necessary to continue to reoptimize the muscle coordination, in particular after the strength training sessions that focused on increasing maximum isometric muscle force.

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Effects of a Songahm Taekwondo Tournament on Vertical Jump and Technical-Tactical Performance in Athletes of the Brazilian National Team

Human Movement ◽

10.1515/humo-2016-0020 ◽

2016 ◽

Vol 17 (3) ◽

Author(s):

Daniele Detanico ◽

Nicole Vitório Librizzi ◽

Marina Saldanha Da Silva Athayde

Keyword(s):

Level Set ◽

Repeated Measures ◽

Perceived Exertion ◽

Vertical Jump ◽

Jump Height ◽

Significance Level ◽

National Team ◽

Jump Test ◽

Before And After ◽

Post Hoc

AbstractThe study aimed to verify the effects of a simulated taekwondo tournament on vertical jump as well as technical and tactical performance in athletes of the Brazilian national team.The study involved 10 male Songahm taekwondo athletes. They took part in a simulated tournament in sparring modality, comprising four 2-minute fights with different opponents. Before and after each fight, the athletes performed the Sargent Jump Test and were asked to indicate the rate of the perceived exertion (RPE). In addition, the fights were recorded and some technical and tactical variables were analysed, namely the number of kicks, effectiveness, and technical variety. The analysis of variance for repeated measures with the Bonferroni post hoc test was used, with the significance level set atNo significant differences in the jump height were observed throughout the fights (The simulated taekwondo tournament had no effect on vertical jump or technical and tactical performance throughout the fights. The athletes were able to recover the effort perception before each new fight.

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