A Cross-Sectional Lower-Body Power Profile of Elite and Subelite Australian Football Players

When an athlete wears a mouthguard, the position of the lower jaw is changed by virtue of the teeth being unable to occlude. Little research is available in in this area, which have indicated both positive impact and no positive impact.ObjectivesThis study aims to explore the influence of the lower jaw position on athletic performance in elite athletes.MethodsA repeated measures study compared two lower jaw positions, the athlete’s normal (habitual) bite and the lower jaw position when the muscles of mastication are at physiological rest (physiological rest bite). 15 athletes completed a medicine ball putt (upper body power), vertical jump (lower body power), sit and reach (composite hamstring flexibility), passive knee flexion (hamstring muscle length) and star excursion balance (stability and balance) tests in each condition.ResultsPaired t-tests showed the physiological rest bite had significant (p<0.05) positive effect on athletic performance for each test. On average the physiological rest bite provided an increase of lower body power (5.8%), upper body power (10%), hamstring flexibility (14%) and balance and stability (4.8%) compared to the habitual bite.ConclusionThis study provides evidence of the need for further research to confirm if the lower jaw position can be optimised for athletic performance in athletes.

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Measures Derived from Panoramic Ultrasonography and Animal-Based Protein Intake Are Related to Muscular Performance in Middle-Aged Adults

Journal of Clinical Medicine ◽

10.3390/jcm10050988 ◽

2021 ◽

Vol 10 (5) ◽

pp. 988

Author(s):

Nathaniel R. Johnson ◽

Christopher J. Kotarsky ◽

Kyle J. Hackney ◽

Kara A. Trautman ◽

Nathan D. Dicks ◽

...

Keyword(s):

Protein Intake ◽

Handgrip Strength ◽

Muscle Size ◽

Dietary Intakes ◽

Lower Body ◽

Linear Regression Models ◽

Middle Aged ◽

Cross Sectional ◽

Muscular Performance ◽

Middle Aged Adults

Ultrasonography advantageously measures skeletal muscle size and quality, but some muscles may be too large to capture with standardized brightness mode (B-mode) imaging. Panoramic ultrasonography can capture more complete images and may more accurately measure muscle size. We investigated measurements made using panoramic compared to B-mode ultrasonography images of the rectus femoris with muscular performance. Concurrently, protein intake plays an important role in preventing sarcopenia; therefore, we also sought to investigate the association between animal-based protein intake (ABPI) and muscular performance. Ninety-one middle-aged adults were recruited. Muscle cross-sectional area (CSA) and thickness were obtained using B-mode and panoramic ultrasound and analyzed with Image J software. Muscular performance was assessed using isokinetic dynamometry, a 30-s chair test, and handgrip strength. Three-day food diaries estimated dietary intakes. Linear regression models determined relationships between measures from ultrasonography and muscular performance. Mixed linear models were used to evaluate the association between ABPI and muscular performance. Muscle CSA from panoramic ultrasonography and ABPI were positively associated with lower-body strength (β ± S.E.; CSA, 42.622 ± 20.024, p = 0.005; ABPI, 65.874 ± 19.855, p = 0.001), lower-body endurance (β ± S.E.; CSA, 595 ± 200.221, p = 0.001; ABPI, 549.944 ± 232.478, p = 0.020), and handgrip strength (β ± S.E.; CSA, 6.966 ± 3.328, p = 0.004; ABPI, 0.349 ± 0.171, p = 0.045). Panoramic ultrasound shows promise as a method for assessing sarcopenia. ABPI is related to better muscular performance.

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Influence of Playing Standard on Upper- and Lower-Body Strength, Power, and Velocity Characteristics of Elite Rugby League Players

Journal of Functional Morphology and Kinesiology ◽

10.3390/jfmk4020022 ◽

2019 ◽

Vol 4 (2) ◽

pp. 22 ◽

Cited By ~ 3

Author(s):

John F. T. Fernandes ◽

Matthew Daniels ◽

Liam Myler ◽

Craig Twist

Keyword(s):

Bench Press ◽

Peak Velocity ◽

First Grade ◽

Rugby League ◽

Power Relationships ◽

Lower Body ◽

Body Strength ◽

Lower Body Strength ◽

Lower Body Power ◽

Level Resistance

Background: To compare load–velocity and load–power relationships among first grade (n = 26, age 22.9 ± 4.3 years), academy (n = 23, age 17.1 ± 1.0 years), and scholarship (n = 16, age 15.4 ± 0.5 years) Super League rugby league players. Methods: Participants completed assessments of maximal upper- and lower-body strength (1RM) and peak velocity and power at 20, 40, 60, and 80 kg during bench press and squat exercises, in a randomised order. Results: Bench press and squat 1RM were highest for first grade players compared with other standards (effect size (ES) = −0.43 to −3.18). Peak velocities during bench and squat were greater in the higher playing standards (ES = −0.39 to −3.72 range), except for the squat at 20 and 40 kg. Peak power was higher in the better playing standards for all loads and exercises. For all three groups, velocity was correlated to optimal bench press power (r = 0.514 to 0.766), but only 1RM was related to optimal power (r = 0.635) in the scholarship players. Only squat 1RM in the academy was related to optimal squat power (r = 0.505). Conclusions: Peak velocity and power are key physical qualities to be developed that enable progression from junior elite rugby league to first grade level. Resistance training should emphasise both maximal strength and velocity components, in order to optimise upper- and lower-body power in professional rugby league players.

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TENDON RESPONSE IN ACHILLES TENDON OF AUSTRALIAN FOOTBALL PLAYERS USING ULTRASOUND TISSUE CHARACTERISATION

British Journal of Sports Medicine ◽

10.1136/bjsports-2013-092459.30 ◽

2013 ◽

Vol 47 (9) ◽

pp. e2.24-e2

Author(s):

S Rosengarten ◽

S I Docking ◽

J T M van Schie ◽

J Daffy ◽

J L Cook

Keyword(s):

Achilles Tendon ◽

Football Players ◽

Tissue Characterisation ◽

Australian Football

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Influence of Neuromuscular Fatigue on Accelerometer Load in Elite Australian Football Players

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.8.4.373 ◽

2013 ◽

Vol 8 (4) ◽

pp. 373-378 ◽

Cited By ~ 59

Author(s):

Stuart J. Cormack ◽

Mitchell G. Mooney ◽

Will Morgan ◽

Michael R. McGuigan

Keyword(s):

High Speed ◽

Neuromuscular Fatigue ◽

Football Players ◽

Countermovement Jump ◽

Baseline Measure ◽

Running Activity ◽

Australian Football ◽

Percent Contribution ◽

Playing Time ◽

The Impact

Purpose:To determine the impact of neuromuscular fatigue (NMF) assessed from variables obtained during a countermovement jump on exercise intensity measured with triaxial accelerometers (load per minute [LPM]) and the association between LPM and measures of running activity in elite Australian Football.Methods:Seventeen elite Australian Football players performed the Yo-Yo Intermittent Recovery Test level 2 (Yo-Yo IR2) and provided a baseline measure of NMF (flight time:contraction time [FT:CT]) from a countermovement jump before the season. Weekly samples of FT:CT, coaches’ rating of performance (votes), LPM, and percent contribution of the 3 vectors from the accelerometers in addition to high-speed-running meters per minute at >15 km/h and total distance relative to playing time (m/min) from matches were collected. Samples were divided into fatigued and nonfatigued groups based on reductions in FT:CT. Percent contributions of vectors to LPM were assessed to determine the likelihood of a meaningful difference between fatigued and nonfatigued groups. Pearson correlations were calculated to determine relationships between accelerometer vectors and running variables, votes, and Yo-Yo IR2 score.Results:Fatigue reduced the contribution of the vertical vector by (mean ± 90% CI) –5.8% ± 6.1% (86% likely) and the number of practically important correlations.Conclusions:NMF affects the contribution of individual vectors to total LPM, with a likely tendency toward more running at low speed and less acceleration. Fatigue appears to limit the influence of the aerobic and anaerobic qualities assessed via the Yo-Yo IR2 test on LPM and seems implicated in pacing.

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