Sports Sciences Commons^™

Effects Of Preventative Ankle Taping On Planned Change-Of-Direction And Reactive Agility Performance And Ankle Muscle Activity In Basketballers, Matthew D. Jeffriess, Adrian B. Schultz, Tye S. Mcgann, Samuel J. Callaghan, Robert G. Lockie

Research outputs 2014 to 2021

This study investigated the effects of preventative ankle taping on planned change-of-direction and reactive agility performance and peak ankle muscle activity in basketballers. Twenty male basketballers (age = 22.30 ± 3.97 years; height = 1.84 ± 0.09 meters; body mass = 85.96 ± 11.88 kilograms) with no ankle pathologies attended two testing sessions. Within each session, subjects completed six planned and six reactive randomized trials (three to the left and three to the right for each condition) of the Y-shaped agility test, which was recorded by timing lights. In one session, subjects had both ankles un-taped. In the other, both …

Certain Actions From The Functional Movement Screen Do Not Provide An Indication Of Dynamic Stability, Robert G. Lockie, Samuel J. Callaghan, Corrin A. Jordan, Tawni M. Luczo, Matthwe D. Jeffriess, Farzad Jalilvand, Adrian B. Schultz

Research outputs 2014 to 2021

Dynamic stability is an essential physical component for team sport athletes. Certain Functional Movement Screen (FMS) exercises (deep squat; left- and right-leg hurdle step; left- and right-leg in-line lunge [ILL]; left- and right-leg active straight-leg raise; and trunk stability push-up [TSPU]) have been suggested as providing an indication of dynamic stability. No research has investigated relationships between these screens and an established test of dynamic stability such as the modified Star Excursion Balance Test (mSEBT), which measures lower-limb reach distance in posteromedial, medial, and anteromedial directions, in team sport athletes. Forty-one male and female team sport athletes completed the screens …

Changes In The Number Of Circulating Cd34+ Cells After Eccentric Exercise Of The Elbow Flexors In Relation To Muscle Damage, Ho Seong Lee, Makii Muthalib, Takayuki Akimoto, Kazunori Nosaka

Research outputs 2014 to 2021

Background: It has been reported that strenuous exercise increases the number of bone marrow-derived progenitor cells such as CD34⁺ cells in the blood, but no previous studies have investigated the changes in circulating CD34⁺ cells following resistance exercise. This study tested the hypothesis that the number of CD34⁺ cells in the blood would increase after eccentric exercise of the elbow flexors, but decrease in recovery, and the magnitude of the changes would be dependent on the magnitude of muscle damage.

Methods: Nine men (28.0 ± 6.6 years) performed exercises consisting of 10 sets of six maximal voluntary …

A Comparison Of Two Gluteus Maximus Emg Maximum Voluntary Isometric Contraction Positions, Bret Contreras, Andrew D. Vigotsky, Chris Beardsley, John B. Cronin

Research outputs 2014 to 2021

Background. The purpose of this study was to compare the peak electromyography (EMG) of the most commonly-used position in the literature, the prone bent-leg (90°) hip extension against manual resistance applied to the distal thigh (PRONE), to a novel position, the standing glute squeeze (SQUEEZE). Methods. Surface EMG electrodes were placed on the upper and lower gluteus maximus of thirteen recreationally active females (age = 28.9 years; height = 164 cm; body mass = 58.2 kg), before three maximum voluntary isometric contraction (MVIC) trials for each position were obtained in a randomized, counterbalanced fashion. Results. No statistically significant (p …

Relationships Between Lower-Body Muscle Structure And, Lower-Body Strength, Explosiveness And Eccentric Leg Stiffness In Adolescent Athletes, Josh Secomb, Sophia Nimphius, Oliver R. Farley, Lina Lundgren, Tai T. Tran, Jeremy M. Sheppard

Research outputs 2014 to 2021

The purpose of the present study was to determine whether any relationships were present between lower-body muscle structure and, lower-body strength, variables measured during a counter-movement jump (CMJ) and squat jump (SJ), and eccentric leg stiffness, in adolescent athletes. Thirty junior male (n = 23) and female (n = 7) surfing athletes (14.8 ± 1.7 y; 1.63 ± 0.09 m; 54.8 ± 12.1 kg) undertook lower-body muscle structure assessment with ultrasonography and performed a; CMJ, SJ and an isomet-ric mid-thigh pull (IMTP). In addition, eccentric leg stiffness was calculated from variables of the CMJ and IMTP. Moderate to very large …

Impact Of Altitude On Power Output During Cycling Stage Racing, Laura A. Garvican-Lewis, Bradley Clark, David T. Martin, Yorck O. Schumacher, Warren Mcdonald, Brian Stephens, Fuhai Ma, Kevin G. Thompson, Christopher J. Gore, Paolo Mensaspa

Research outputs 2014 to 2021

Purpose The purpose of this study was to quantify the effects of moderate-high altitude on power output, cadence, speed and heart rate during a multi-day cycling tour. Methods Power output, heart rate, speed and cadence were collected from elite male road cyclists during maximal efforts of 5, 15, 30, 60, 240 and 600 s. The efforts were completed in a laboratory power-profile assessment, and spontaneously during a cycling race simulation near sea-level and an international cycling race at moderate-high altitude. Matched data from the laboratory power-profile and the highest maximal mean power output (MMP) and corresponding speed and heart rate …

Eccentric Loading Increases Peak Torque Angle Of The Ankle Plantar Flexors In Healthy Volunteers, Matthew Wellisch, Peter Hamer, Luke Hopper, Max Bulsara, James Debenham

Research outputs 2014 to 2021

Eccentric loading of the ankle plantar Flexor's (PF) has demonstrated clinical efficacy in the conservative treatment of Achilles tendinopathy, however, its mechanism of therapeutic benefit remains unclear. The purpose of this study was to examine the effects of PF eccentric loading on PF angle to peak torque (AtPT), peak torque (PT) and lower limb vertical stiffness. Thirty healthy volunteers were randomised to an eccentric (n=15) or concentric (n=13) exercise group. A 10-week loading programme of the ankle plantar flexors was completed. AtPT, PT and vertical stiffness were compared within and between groups before and after the interventions. AtPT increased in …

Do Dance Floor Force Reduction And Static Stiffness Represent Dynamic Floor Stiffness During Dance Landings?, Luke S. Hopper, Jacqueline A. Alderson, Bruce C. Elliott, Timothy R. Ackland, Paul R. Fleming

Research outputs 2014 to 2021

Dance training on floors that are not 'sprung' are assumed to have direct implications for injury. Standards for dance floor manufacture in Europe and North America quantify floor force reduction by measuring the impact forces of drop masses. In addition, many studies of human mechanical adaptations to varied surfaces, have quantified test surfaces using measures of static stiffness. It is unclear whether these methods for the measurement of floor mechanical properties actually reflect dancer requirements or floor behaviour under dancer loading. The aim of this study was to compare the force reduction, static stiffness and dynamic stiffness of a range …

Pgc-1Α Mediated Muscle Aerobic Adaptations To Exercise, Heat And Cold Exposure, Mohammed Ihsan, Greig Watson, Chris R. Abbiss

Research outputs 2014 to 2021

PGC-1α is regarded as a key regulator of mitochondrial biogenesis due to its central role in regulating the activity of key transcription factors associated with encoding mitochondrial components. Additionally, PGC-1α has shown to mediate adaptations that increase fat metabolism and angiogenesis, contributing to the overall oxidative phenotype of the muscle. While it is well established that exercise is a potent stimulator of PGC-1α, recent evidence indicates that heat and cold exposures may also influence mitochondrial biogenesis through the up-regulation of PGC-1α. This highlights the potential use of these modalities in conjunction with exercise to enhance training adaptations. As such, the …

Factors Influencing Pacing In Triathlon, Sam Shi Xuan Wu, Jeremiah P. Peiffer, Jeanick Brisswalter, Kazunori Nosaka, Chris Abbiss

Research outputs 2014 to 2021

Triathlon is a multisport event consisting of sequential swim, cycle, and run disciplines performed over a variety of distances. This complex and unique sport requires athletes to appropriately distribute their speed or energy expenditure (ie, pacing) within each discipline as well as over the entire event. As with most physical activity, the regulation of pacing in triathlon may be influenced by a multitude of intrinsic and extrinsic factors. The majority of current research focuses mainly on the Olympic distance, whilst much less literature is available on other triathlon distances such as the sprint, half-Ironman, and Ironman distances. Furthermore, little is …

Iron Status And The Acute Post-Exercise Hepcidin Response In Athletes, Peter Peeling, Marc Sim, Claire E. Badenhorst, Brian Dawson, Andrew D. Govus, Chris R. Abbiss, Dorine W. Swinkels, Debbie Trinder

Research outputs 2014 to 2021

This study explored the relationship between serum ferritin and hepcidin in athletes. Baseline serum ferritin levels of 54 athletes from the control trial of five investigations conducted in our laboratory were considered; athletes were grouped according to values 100 mg/L (SF>100). Data pooling resulted in each athlete completing one of five running sessions: (1) 8x3 min at 85% vVO2peak; (2) 5x4 min at 90% vVO2peak; (3) 90 min continuous at 75% vVO2peak; (4) 40 min continuous at 75% vVO 2peak; (5) 40 min continuous at 65% vVO2peak. Athletes from each running session were represented amongst all four groups; hence, …

Changes In Muscle Damage Markers In Female Basketball Players, Alexandre Moreira, Ken Nosaka, Joao Antonio Nunes, Luis Viveiros, Athanasios Z. Jamurtas, Marcelo Saldanha Aoki

Research outputs 2014 to 2021

The aim of the present study was to investigate changes in muscle soreness, blood muscle damage markers, muscle strength and agility following an official basketball match. Eleven elite female professional basketball players (27.4 ± 4.8 years, 179.5 ± 5.5 cm, 72.0 ± 7.8 kg) of a team participated in this study. The official match was the seventh match of the season in the first phase of the Brazilian National Female Basketball Championship. Muscle soreness, plasma creatine kinase activity (CK), and myoglobin concentration (Mb) were determined before and after the match (post-match, 24 and 48 hours after the match). The 1RM …

Influence Of Age And Sex On Pacing During Sprint, Olympic, Half-Ironman And Ironman Triathlons. Part B, Sam Shi Xuan Wu, Jeremiah J. Peiffer, Jeanick Brisswalter, Wing Y. Lau, Kazunori Nosaka, Christopher Abbiss

Research outputs 2014 to 2021

The aim of this study was to investigate the influence of biological sex and age on the pacing strategies adopted by non-drafting top triathletes during the cycle and run disciplines of a Sprint, Olympic, half-Ironman and Ironman triathlon. Split times of the top 20% non-elite males (n=468) and females (n=146) were determined using official race transponders and a video capture system for pre-determined sections of the cycle and run disciplines of four triathlon distances. Indices of pacing were calculated to compare between sexes and age-groups. Results of this study indicated that different pacing strategies were adopted between athletes of different …

Muscle Damage After A Tennis Match In Young Players, Rodrigo Vitasovic Gomes, Ricardo Santos, Ken Nosaka, Alexandre Moreira, Elen Miyabara, Marcelo Saldanha Aoki

Research outputs 2014 to 2021

The present study investigated changes in indirect markers of muscle damage following a simulated tennis match play using nationally ranked young (17.6 ± 1.4 years) male tennis players. Ten young athletes played a 3-hour simulated match play on outdoor red clay courts following the International Tennis Federation rules. Muscle soreness, plasma creatine kinase activity (CK), serum myoglobin concentration (Mb), one repetition maximum (1RM) squat strength, and squat jump (SJ) and counter movement jump (CMJ) heights were assessed before, immediately after, and 24 and 48 h after the simulated match play. All parameters were also evaluated in a non-exercised group (control …

A Dynamic Evaluation Of How Kick Point Location Influences Swing Parameters And Related Launch Conditions, Christopher Joyce, Angus Burnett, Alvaro Reyes, Stephen Herbert

Research outputs 2014 to 2021

In golf, many parameters of the driver can be modified to maximise hitting distance. The main objective of this study was to determine whether drivers fitted with shafts having high and low kick points would alter selected swing parameters and related launch conditions. In total, 12 elite male golfers (handicap score = 1.2 ± 1.8) had three shots analysed for two drivers fitted with 'stiff' shafts with differing kick point location. Stiffness profiles of these shafts were also measured. Five swing and related launch parameters were measured using a real-time launch monitor. The locations of the low and high kick …

Influence Of Race Distance And Biological Sex On Age-Related Declines In Triathlon Performance. Part A, Sam Shi Xuan Wu, Jeremiah Peiffer, Jeanick Brisswalter, Wing Y. Lau, Kazunori Nosaka, Chris R. Abbiss

Research outputs 2014 to 2021

This study examined the effect of biological sex and race distance on the age-related declines in swimming, cycling, running and overall performances of the sprint, Olympic, Half-Ironman and Ironman triathlons. Individual discipline and overall performance time of the top 20% non-elite males (n=468) and females (n=146) were compared by categorizing into four 10-year age-groups (20-29, 30-39, 40-49, 50+ years) and normalising to the mean performance time of the fastest age-group for each race. An earlier, larger and faster rate of decline (p=0.01) in performance with ageing was observed in females (≥30 years, 9.3%, 3.0% per decade respectively) and males (≥40 …