This study investigated the impact reaction forces on the elbow when performing a downward short-pole free-drop motion, which mimics the double poling technique in sledge hockey. A prototype was used to model an average male sledge hockey player, dropping from various elbow angles and heights. Motion capture and force plates collected impact force and impulse data. The results showed that elbow angle affects impact force, with lower angles resulting in higher forces. A horizontal release and flexed elbow pose the lowest impact risk, while steeper angles increase risk of injury from high impact forces. Understanding these baseline impact measures can help improve double poling technique and safety in sledge hockey and other para-sports.
The hamstring muscle group is the most frequently injured, representing
approximately 12 to 24% of all athletic injuries.1,2 These injuries may be due to
disproportionate training performed for the quadriceps,3 with hamstring strains
occurring more frequently in those who demonstrated hamstring weakness, and
lower hamstring-to-quadriceps strength ratios.2 Thus, hamstring strength is impor-
tant for athletic performance and injury prevention in a variety of sports.
High chronic training loads and exposure to bouts of maximal velocity running...Fernando Farias
The ability to produce high speeds is considered an important
quality for performance, with athletes shown to achieve 85–94% of
maximal velocity during team sport match-play.3 Well-developed
high-speed running ability and maximal velocity are required of
players during competition in order to beat opposition players
to possession and gain an advantage in attacking and defensive
situations.
The hamstring muscle group is the most frequently injured, representing
approximately 12 to 24% of all athletic injuries.1,2 These injuries may be due to
disproportionate training performed for the quadriceps,3 with hamstring strains
occurring more frequently in those who demonstrated hamstring weakness, and
lower hamstring-to-quadriceps strength ratios.2 Thus, hamstring strength is impor-
tant for athletic performance and injury prevention in a variety of sports.
High chronic training loads and exposure to bouts of maximal velocity running...Fernando Farias
The ability to produce high speeds is considered an important
quality for performance, with athletes shown to achieve 85–94% of
maximal velocity during team sport match-play.3 Well-developed
high-speed running ability and maximal velocity are required of
players during competition in order to beat opposition players
to possession and gain an advantage in attacking and defensive
situations.
Training the vertical jump to head the ball in soccer Fernando Farias
IN MODERN SOCCER, HEADING
THE BALL IS BOTH AN OFFENSIVE
TOOL USED TO SCORE GOALS
AND A DEFENSIVE MEASURE
AGAINST OPPOSING TEAMS. PRO-
FICIENCY IN HEADING THE BALL
REQUIRES PROPER TECHNIQUE IN
CONJUNCTION WITH AN EFFEC-
TIVE VERTICAL JUMP. THE AIM OF
THIS ARTICLE IS TO ADDRESS THE
FACTORS INVOLVED IN VERTICAL
JUMP PERFORMANCE AND HOW
THEY RELATE SPECIFICALLY TO
HEADING THE BALL
Epidemiological studies have consistently shown hamstring
strain injuries (HSIs) to have a high prevalence rate in many
sports, such as sprinting (11%; Lysholm & Wiklander, 1987),
Australian Rules Football (16–23%; Orchard, 2001; Orchard,
Marsden, Lord, & Garlick, 1997) and football (12–14%:
Ekstrand, Hagglund, & Walden, 2011; Hawkins, Hulse,
Wilkinson, Hodson, & Gibson, 2001). The epidemiology and
aetiology of HSI in football has received extensive attention in
the scientific literature (Ekstrand et al., 2011; Woods et al., 2004),
given the economic burden associated with professional
players missing training and competitive fixtures (Woods,
Hawkins, Hulse, & Hodson, 2002). b
Hamstring injuries have increased by 4% annuallyFernando Farias
Muscle injuries are a substantial problem for pro-
fessional football players. They constitute more
than one-third of all time-loss injuries and cause
more than a quarter of the total injury absence in
high-level European professional football clubs.1
Hamstring injury is the most common injury
subtype, representing 12% of all injuries, and a
team with a 25 player-squad typically suffers about
5–6 hamstring injuries each season, equivalent to
more than 80 days involving football activities
(training or matches) lost due to injury.
Bilateral and unilateral vertical ground reaction forcesFernando Farias
The purposes of this study were to assess unilateral and bilateral vertical jump performance
characteristics, and to compare the vertical ground reaction force characteristics of the impulse and landing
phase of a vertical jump between the dominant and non-dominant leg in soccer players.
NSCA National Conference (2013) Podium Presentationcoachademia
Earlier this month, I presented part of my PhD work at the National Strength and Conditioning Association’s National Conference in Las Vegas. These are the slides from the podium presentation which I delivered. If you have any questions about the work presented, then please do get in touch.
Anthony Shield - does strength in the nhe predict hamstring injury MuscleTech Network
Anthony Shield
Senior lecturer, School of Exercise and Nutrition Science Institute of Health and Biomedical Innovation Queensland University of Technology, Brisbane, Australia.
-
Does strength in the Nordic hamstring exercise predict hamstring injury?
(&th MuscleTech Network workshop)
14th October, Barcelona
Tri Athlete - Don\'t Let Bad Mechanics Sideline Your Trainingtnessler
This presentation provides the most current research related to running mechanics and how to train to prevent some of the most common running injuries.
Analysis of Lower Limb Bilateral Force Asymmetries by Different Vertical Jump...IJRTEMJOURNAL
This study has compared the diagnostic information of lower limb bilateral force asymmetry by
the impulse variable at different vertical jumps techniques. Twenty-nine soccer players carried out six attempts
at each of the vertical jumps, countermovement jump and squat jump, on two synchronized force platforms.
After the calculation of the symmetry index, the athletes were classified as symmetric and asymmetric respecting
a cut-off value of 15%, McNamara’s test compared the diagnostic information among the techniques.
Significant differences were found among the diagnostic information of the different techniques (p<0.05). It is
thus concluded that different vertical jump techniques provide different information in regard to the level of
bilateral force asymmetry in soccer players
Training the vertical jump to head the ball in soccer Fernando Farias
IN MODERN SOCCER, HEADING
THE BALL IS BOTH AN OFFENSIVE
TOOL USED TO SCORE GOALS
AND A DEFENSIVE MEASURE
AGAINST OPPOSING TEAMS. PRO-
FICIENCY IN HEADING THE BALL
REQUIRES PROPER TECHNIQUE IN
CONJUNCTION WITH AN EFFEC-
TIVE VERTICAL JUMP. THE AIM OF
THIS ARTICLE IS TO ADDRESS THE
FACTORS INVOLVED IN VERTICAL
JUMP PERFORMANCE AND HOW
THEY RELATE SPECIFICALLY TO
HEADING THE BALL
Epidemiological studies have consistently shown hamstring
strain injuries (HSIs) to have a high prevalence rate in many
sports, such as sprinting (11%; Lysholm & Wiklander, 1987),
Australian Rules Football (16–23%; Orchard, 2001; Orchard,
Marsden, Lord, & Garlick, 1997) and football (12–14%:
Ekstrand, Hagglund, & Walden, 2011; Hawkins, Hulse,
Wilkinson, Hodson, & Gibson, 2001). The epidemiology and
aetiology of HSI in football has received extensive attention in
the scientific literature (Ekstrand et al., 2011; Woods et al., 2004),
given the economic burden associated with professional
players missing training and competitive fixtures (Woods,
Hawkins, Hulse, & Hodson, 2002). b
Hamstring injuries have increased by 4% annuallyFernando Farias
Muscle injuries are a substantial problem for pro-
fessional football players. They constitute more
than one-third of all time-loss injuries and cause
more than a quarter of the total injury absence in
high-level European professional football clubs.1
Hamstring injury is the most common injury
subtype, representing 12% of all injuries, and a
team with a 25 player-squad typically suffers about
5–6 hamstring injuries each season, equivalent to
more than 80 days involving football activities
(training or matches) lost due to injury.
Bilateral and unilateral vertical ground reaction forcesFernando Farias
The purposes of this study were to assess unilateral and bilateral vertical jump performance
characteristics, and to compare the vertical ground reaction force characteristics of the impulse and landing
phase of a vertical jump between the dominant and non-dominant leg in soccer players.
NSCA National Conference (2013) Podium Presentationcoachademia
Earlier this month, I presented part of my PhD work at the National Strength and Conditioning Association’s National Conference in Las Vegas. These are the slides from the podium presentation which I delivered. If you have any questions about the work presented, then please do get in touch.
Anthony Shield - does strength in the nhe predict hamstring injury MuscleTech Network
Anthony Shield
Senior lecturer, School of Exercise and Nutrition Science Institute of Health and Biomedical Innovation Queensland University of Technology, Brisbane, Australia.
-
Does strength in the Nordic hamstring exercise predict hamstring injury?
(&th MuscleTech Network workshop)
14th October, Barcelona
Tri Athlete - Don\'t Let Bad Mechanics Sideline Your Trainingtnessler
This presentation provides the most current research related to running mechanics and how to train to prevent some of the most common running injuries.
Analysis of Lower Limb Bilateral Force Asymmetries by Different Vertical Jump...IJRTEMJOURNAL
This study has compared the diagnostic information of lower limb bilateral force asymmetry by
the impulse variable at different vertical jumps techniques. Twenty-nine soccer players carried out six attempts
at each of the vertical jumps, countermovement jump and squat jump, on two synchronized force platforms.
After the calculation of the symmetry index, the athletes were classified as symmetric and asymmetric respecting
a cut-off value of 15%, McNamara’s test compared the diagnostic information among the techniques.
Significant differences were found among the diagnostic information of the different techniques (p<0.05). It is
thus concluded that different vertical jump techniques provide different information in regard to the level of
bilateral force asymmetry in soccer players
Mechanics of the human hamstring muscles during sprintingFernando Farias
As peak musculotendon
force and strain for BF
LH
, ST, and SM occurred around the same time during terminal swing, it is suggested that this period in the
stride cycle may be when the biarticular hamstrings are at greatest injury risk. On this basis, hamstring injury prevention or rehabilitation
programs should preferentially target strengthening exercises that involve eccentric contractions performed with high loads at longer
musculotendon lengths.
Prehabilitation and Improved Performance for AthletesTina Nguyen
A prehabilitation program to reduce the incidence of anterior cruciate ligament (ACL) injuries. Researched and written as a final project upon gradate school.
EFFECT OF POSTURAL CONTROL BIOMECHANICAL GAIN ON PSYCHOPHYSICAL DETECTION THR...ijbbjournal
A Sliding Linear Investigative Platform for Assessing Lower Limb Stability (SLIP-FALLS) was employed to study postural control biomechanical reaction to external perturbations in a short ≤16mm postural perturbation. Head acceleration were evaluated while blindfolded subjects stood on a platform that was given a short anterior perturbation presented in one of 2 sequential 4s intervals (2-Alternative-ForcedChoice) for a set of 30 trials. Anterior-Posterior head acceleration (Head Accl AP) were investigated among the movement and non- movement intervals for the healthy adults. A strong ringing signal was observed in Head Accl AP movement interval that was absent in non-movement interval. A positive power
law trading relationship was found between Head Accl AP gain and move length standing blindfolded subjects. This could explain the observed negative power law relationship between translation length and peak acceleration threshold in previous psychophysical detection threshold studies.
1. Baseline Impact Reaction Forces in a Seated Downward Short-Pole Free-Drop:
A Biomechanical Investigation of Elbow Angle upon Impact in the Sport of Sledge Hockey
Gal, AM, Chan, ADC & Hay, DC
Understanding external reaction forces acting upon a dynamic system presents a difficult task
biomechanically; internal forces are complex and inexperienced scientifically.Baseline measures (BM)
enhance the depth into which results can be derived. BM can be investigated by isolating the point of
rotation using a solid-static systemto determine the minimum external force exerted onto the system;
this study’s focus was the effect of gravitational force acting on a solid limb upon impact. Using a test-
retestapproach,BMforimpactforces were determinedfrom adownwardpoling free-dropof avalidated
prototype mimicking an average male (80kg) solid-static single-armed sledge hockey player; retest
incorporatedset-upimprovementssuggestedfrompreviousstudies(*).Limbmorphologywas mirrored
using two 1.3kg wrist-weights (medial/lateral upper arm) and a single 1.2kg ankle-weight (medial
forearm). Elbow (E) and wrist-stick angles were fixed at 150o
, 135o
, 120o
and 45o
, respectively. Three
useable trials where collected for each E at above, below and horizon drop heights* (DH). Marker
trajectories were acquired by a Vicon motion capture system at 250Hz* and impact forces by a Kistler
force plate at 2000Hz* (no filter)*; initial impact to point of recoil. Trial lengths(TL) were consistent for
E120 and E150, 4.0x10-3
s and 5.0x10-3
s respectively;TL for E135 rangedbetweenthe two (TL135ave 4.4x10-3
s),
data was averaged by TL then combined providing two sets of results for E135 affecting ranking order in
some cases.Toprankingresultsindicatedthataveraged-peakreactionforce (RxtSum) was1637N fromTL4.0
with a maximal averaged-impulse (JtSum) of 3.94Ns from TL5.0; RxtAbove 1812N (TL4.0) with JtAbove 4.25Ns
(TL4.0),RxtHorizon 1469N (TL4.5) withJtHorizon 3.86Ns (TL4.5), and RxtBelow 1568N (TL5.0) withJtBelow 3.89Ns (TL4.5).
Combined TL resulted in a peak RxSum of 1567N (1511N+
including a single trial outlier) with an JSum of
3.87Ns (3.83Ns+
); RxAbove 1639N (1321N+
), RxHorizon 1454N, and RxBelow 1544N with JAbove 4.15Ns (3.31Ns+
),
JHorizon 3.53Ns and JBelow 3.72Ns. The highest ranking averaged-peak impact recorded for E was RxE135TL4.0
1709N andRxE135 1617N; above the horizon RxE150 1774N, horizon RxE135TL4.5 1485N and RxE120 1473N, and
below RxE135TL4.5 1715N andRxE135 1642N. BM indicatedthatEdoeseffectRx uponimpact suggestinga45o
forearmis not an optimal impactangle when concernedwithimpact-inducedtrauma;inversely,optimal
for force-produced locomotion (approximately 10ms-1
change in arm momentum). Elevated DH and
shorter TL indicated larger Rx and J, as hypothesized. Horizontal release and flexed E proved to be the
safest impact illustrating minimal Rx. Despite DH and/or TL Rx data presented analogous curves
throughouteachEindicatingasingularforce-transferpathwaybackontothe system;impactisconsistent.
Para-sports present difficultly in fundamental skill development, each participant provides unique
limitations/parametres. Understanding fundamental skillsets allows for educated advancement and
modificationsof the skillandall subsequentvariations.Doublepolingis locomotioninsledgehockey; this
research provides advancement to this scientifically deficit sport and is transferrable to other double
polingpara-sportssuchas alpinepush-starts.Para-athleteswhoare shoulder-dependentincrease the risk
of overuse and/or overloading injury; advancement in fundamental tasks can greatly amend this
inevitable outcome.
Acknowledgement M. Lamontagne (Human Movement Biomechanics Laboratory), B. Hallgrimsson
(Industrial Design) & M. Haefele (Research Assistant)
2. References:
Bernardi, M., Janssen, T., Bortolan L., Pellegrini, B., Fischer, G. & Schena, F. (2013). Kinematics of cross-
country sit skiing during a paralympic race. Journal of Electromyography and Kinesiology, 23, 94-101.
Gal AM, Chan ADC & Hay DC. (2015). Investigating the seated double poling cycle: Identifying baseline
measures for the preparation phase. A. Gal [et al.] (sciencesconf.org:isbs2015:59230).
Gal AM, Chan ADC & Hay DC. (2015). Validating a solid-static single-armed male prototype tasked to
produce dynamic movement from the shoulder through the preparation phase. IFMBE Proceedings.
Gal AM, Hay DC & Chan ADC.(2014) 2 and 3-dimensional analysisof the linearstrokingcycle inthe sport
of sledge hockey:Glenohumeraljointkinematic,kineticandsurface EMGmuscle modellingonandoff ice.
13th
3D AHM :108-111 ISBN 9782880748562.
Holmberg, H., Lindinger, S., Stoggl, T., Eitzlmair, E. & Muller, E. (2005). Biomechanical analysis of double
poling in elite cross-country skiers. Medicine & Science in Sports & Exercise, 37(5):807-818.
Lomond,K.& Wiseman,R.(2003). Sledge hockeymechanicstake toll onshoulders:Analysisof propulsion
technique can help experts designtraining programs to prevent injury. Journal of Bio-mechanics, 10(3):
71-76.
Veeger,H.E.J.,&vanderHelmF.C.T.(2007).Shoulderfunction:The perfectcompromise betweenmobility
and stability. Journal of Biomechanics, 40, 2119-2129.