Alan Pearce

Swinburne University of Technology · Department of Health Science

Concussion injury results in a rapid onset of transient neurological impairment that can resolve quickly, or sometimes evolve over time, but usually resolve within seven to ten days. However, a small but noticeable cohort (~10%) of individuals continue to experience persistent lingering effects, particularly fatigue, and recognized as post-concussi...

The first case report of chronic traumatic encephalopathy (CTE) in a National Football League player in 2005 opened the floodgates for the identification of CTE in American football. CTE is now reported in ex-players of other contact sports, including ice hockey, soccer, rugby union, and most recently in Australian rugby league. To date, repetitive...

Aim: This study investigated the somatosensory and corticomotor physiology of retired contact sport athletes with a history of repeated concussion/subconcussion head trauma. Methods: Retired male athletes with a history of playing contact sports and repeated head trauma (n = 122) were divided into two groups: those who expressed concerns regarding...

We report the first case of CTE in a former professional female footballer.

International concern continues regarding the association between the long-term neurophysiologic changes from repetitive neurotrauma associated with contact and collision sports. This study describes corticomotor changes in retired contact/collision sport athletes and controls, between the ages of 30 and 70 years. Retired athletes (n = 152; 49.1 ±...

Purpose The effects of low-intensity exercise, heat-induced hypo-hydration and rehydration on maximal strength and the underlying neurophysiological mechanisms are not well understood. Methods To assess this, 12 participants took part in a randomised crossover study, in a prolonged (3 h) submaximal (60 W) cycling protocol under 3 conditions: (i) i...

The effects of non-concussive impacts in contact-sports such as in Australian rules football (ARF) are still largely unexplored. These impacts are often but not always lower in intensity, but occur more frequently than actual concussions. Since non-concussive impacts are often asymptomatic, their significance may be underestimated. Acute or subacut...

As Australia's biggest sports codes come into finals, their lofty talk on protecting players from concussions will be put to the test.

Aim of the study Interest continues investigating pathophysiology of athlete cohorts with a history involving cumulative career exposure of repeated concussion and non-concussion impacts. One area yet to be explored involves the somatosensory system. Using a novel sensorimotor technique, this study measured the somatosensory system in retired conta...

Aim Repetitive head impact exposure, from contact and collision sports, are increasingly being attributed to increased risk of neurodegenerative disease in aging athletes. This exploratory study investigated the association of playing career in retired professional contact sport athletes with cortical neurophysiology via transcranial magnetic stimu...

Attention and awareness regarding concussion injury in Australia has significantly increased in the last decade. While most of this increase is due to discussion regarding concussions from sporting endeavours, the majority of concussions are from non-sport environments including motor vehicle crashes, workplace incidents, falls, accidents, assault...

Opinion piece on recent medical retirements in the Australian Football League. https://theconversation.com/are-2-mid-career-afl-retirements-a-sign-australian-athletes-are-taking-brain-health-more-seriously-228197

Sport-related concussions (SRCs) are a mild traumatic brain injury (mTBI) that induces transient symptoms in athletes. These symptoms provide avenues for developing emerging technologies to diagnose SRCs, in particular ocular and vestibular dysfunction. The following study aims to assess the reliability of visual smooth-pursuit technology (EyeGuide...

Objectives The SNAP-CTE Study aims to identify features and characteristics of the in-life experience of those who may be suffering from Chronic Traumatic Encephalopathy (CTE) and correlated Traumatic Encephalopathy Syndrome (TES). A cohort of 20 participants were included in the preliminary findings. Methods 20 participants with a history of mTBI...

This study explored professional male Australian rules football players leaving the Australian Football League (AFL), either from retirement or from deselected from their team. Identified athletes (n = 425) transitioning from the AFL competition from years 2019 to 2021 were invited to participate in an anonymous online survey with 60% completing th...

Background: Transcranial Alternating Current Stimulation (tACS) employs low-intensity sinusoidal currents to influence cortical plasticity and motor function. Despite extensive research, inconsistent results require a comprehensive review of tACS efficacy. Objective: This study systematically assesses tACS effects on corticospinal and intracortical...

Background: Functional gastrointestinal disorders (FGIDs) are common, difficult-to-manage conditions. Probiotics are emerging as a dietary component that influence gastrointestinal (GI) health. We conducted a double-blinded randomised controlled trial of a proprietary strain of deactivated Bacillus subtilis (BG01-4™) high in branched-chain fatty a...

Background: Transcranial Alternating Current Stimulation (tACS) employs low-intensity sinusoidal currents to influence cortical plasticity and motor function. Despite extensive research, inconsistent results require a comprehensive review of tACS efficacy. Objective: This study systematically assesses tACS effects on corticospinal and intracortica...

Understanding the association between personality traits and cortisol expression may assist in monitoring and managing mental health in athletes. This study used a singlegroup case study design to quantify the psychophysiological profiles of 26 male athletes from one professional Australian Rules football team (mean age 22.5 ± 4.3 years). Athletes...

Commentary on recent Australian Parliament Inquiry into Concussion and Repetitive Head Trauma in Sport

Commentary about the first study reporting CTE in young athletes under 30 years of age

Mild traumatic brain injury (mTBI) represents a significant burden for individuals, economies, and healthcare systems worldwide. Recovery protocols focus on medication and physiotherapy-based interventions. Animal studies have shown that antioxidants, branched-chain amino acids and omega-3 fatty acids may improve neurophysiological outcomes after T...

In addition to the established postural control role of the reticulospinal tract (RST), there has been an increasing interest on its involvement in strength, motor recovery, and other gross motor functions. However, there are no reviews that have systematically assessed the overall motor function of the RST. Therefore, we aimed to determine the rol...

Commentary regarding the first case of CTE in a female professional athlete

INTRODUCTION: Thermoregulatory sweating, coupled with inadequate fluid intake, leads to intracellular fluid losses from skeletal muscle and neural tissue. The effects of heat-induced hypo-hydration and rehydration on maximal strength and underlying neurophysiological mechanisms are not well understood. Therefore, this study aimed to investigate the...

This study aimed to quantitatively investigate and report the biomechanical characteristics of concussive and sub-concussive impacts in youth sports. A systematic search was conducted in September 2022 to identify biomechanical impact studies in athletes ≤18 years of age. Twenty-six studies met the inclusion criteria for quantitative synthesis and...

Mild traumatic brain injury (mTBI) is the most common brain injury, seen in sports, fall, vehicle, or workplace injuries. Concussion is the most common type of mTBI. Assessment of impairments from concussion is evolving, with oculomotor testing suggested as a key component in a multimodality diagnostic protocol. The aim of this study was to evaluat...

Background: Functional gastrointestinal disorders (FGIDs) are a common, difficult to manage condition. Branched chain fatty acids are emerging as a dietary component that influence gastrointestinal (GI) health. We conducted a double blinded randomized controlled trial of a proprietary strain of deactivated Bacillus subtilis (BG01-4™) that produce b...

Mild traumatic brain injury (mTBI) is the most common brain injury, seen in sports, falls, vehicle, or workplace injuries. Concussion is the most common type of mTBI. Assessment of impairments from concussion are evolving, with oculomotor testing suggested as a key component in a multi-modality diagnostic protocol. The aim of this study was to eval...

International concern regarding the association between repetitive neurotrauma in sport and long term concerns with ageing continues. While previous studies have reported older (i.e. over 50 years) our study describes corticomotor changes across the lifespan between retired contact sport athletes, between the ages of 30 and 70 years. Retired athlet...

Primary Objective: To investigate the effect of home and away game travel on risk of concussion across different levels of rugby union. Research Design: Exploration study across school, university, and professional rugby teams. Methods and Procedures: Retrospective analysis of concussion incidence and symptomology of surveillance data and prospect...

Measurement of the adverse outcomes of repeated head trauma in athletes is often achieved using tests where the comparator is ‘accuracy’. While it is expected that ex-athletes would perform worse than controls, previous studies have shown inconsistent results. Here we have attempted to address these inconsistencies from a different perspective by q...

Managing the health and wellbeing of full-time professional athletes is a multifaceted task. In elite high-performance environments, medical staff and strength training coaches attempt to identify improved methods to monitor player health. Monitoring player health could indicate potential injury risk and assist in adjustments to training and worklo...

The emphasis of this study was to interview ex-professional male rugby union players (n = 23, mean age 35.5 ± 4.7 years) and discuss concussion management during their careers. In this study, two major themes were identified: (1) the duty of care to professional rugby union players by medical personnel, coaching staff, and owners of professional cl...

When mild traumatic brain injury (mTBI) occurs following an impact on the head or body, the brain is disrupted leading to a series of metabolic events that may alter the brain's ability to function and repair itself. These changes may place increased nutritional demands on the body. Little is known on whether nutritional interventions are safe for...

This study aimed to synthesize and quantify the sex-based differences in concussion incidences rate and associated mechanism of injuries in team bat/stick sports. Following a systematic search across five electronic databases, 46 studies were included in the review; 24 were included in the incidence rate (IR) meta-analysis and 13 of the 24 studies...

Background: Worldwide, 86 million individuals over the age of 20 were diagnosed with knee osteoarthritis (KOA) in 2020. Hallmark features of KOA are the loss in knee extensor strength, increasing knee pain severity, and deficits in functional performance. There is a critical need for the investigation into potential cost-effective therapeutic inter...

Traumatic brain injuries (TBIs) are often referred to as the ‘silent epidemic’ because many injuries go unrecognised(Reference Rusnak1). Epidemiological data estimates the incidence of TBI at 27.08 million cases annually, with age-standardised incidence rates at 369 per 100,000 population(Reference James, Theadom and Ellenboge2). Traumatic brain in...

Chronic traumatic encephalopathy (CTE) is a neurodegenerative disease associated with a history of repetitive head impacts (RHI). CTE was described in boxers as early as the 1920s and by the 1950s it was widely accepted that hits to the head caused some boxers to become “punch drunk.” However, the recent discovery of CTE in American and Australian-...

Introduction There is limited research on the on-field performance of previously concussed athletes. The aim of this exploratory study was to investigate athlete technical performance pre- and post-concussion in Australian Football. Methods Using publicly available data, male athletes who sustained a concussion during the 2016–19 professional Aust...

Background: Concussion in sport is an ongoing global concern. The head injury assessment (HIA) by the field of play is acknowledged as the first step in recognising and identifying concussion. While previous systematic literature reviews have evaluated the sensitivity of side-line screening tools and assessment protocols, no systematic review has e...

The purpose of this study was to examine Australian Football athletes' responses to a grade one muscular injury from a psychophysiological perspective to understand the strength of the association between stress, optimism, and cortisol. Forty-five players listed with one professional Australian Football club volunteered for this study. Inclusion cr...

Objective To establish the extent to which Rugby Union was a compulsory physical education activity in state-funded secondary schools in England and to understand the views of Subject Leaders for Physical Education with respect to injury risk.MethodA cross-sectional research study using data obtained under the Freedom of Information Act (2000) from...

Obstructive sleep apnea (OSA), a frequently under-diagnosed sleep disorder, may lead to future poor health, performance, and wellbeing. Increased OSA prevalence has been reported in individuals who have had a head injury. We systematically searched EMBASE, PSYCINFO, WEB OF SCIENCE, COCHRANE and PUBMED to 18th June 2022. OSA prevalence and demograph...

In this Perspective we explore the evolution of our understanding of chronic traumatic encephalopathy (CTE) and its relationship with repetitive head injury. As with many neurodegenerative conditions, there is an imperfect correspondence between neuropathology and clinical phenotype, but unlike other neurodegenerative diseases, CTE has a discrete a...

Objectives: This exploratory study quantified professional Australian rules football players transitioning from the Australian Football League (AFL), comparing responses between retiring and delisted players and if the experience of exiting an AFL club influenced the athlete transition process.Design: Online survey research.Method: Identified male...

RECENT revelations of plagiarism by Australian sports neurologist Dr Paul McCrory () have sent shockwaves through professional sporting bodies internationally. As a leading member of the international Concussion in Sport Group (CISG) for over 20 years, Dr McCrory’s downfall has cast doubt over international consensus guidelines for the management o...

The focus of this study was to interview retired professional rugby union players (≤10 years since retirement) to discuss their careers in the game of rugby union. These interviews explored their experiences of being a professional rugby player, with respect to physical injury, concussion incidence and concussion management. In addition, the aims w...

Objective: This study explored psychophysiological stress in professional Australian Rules football athletes across the course of one competitive season. Methods: A sample of eight players listed with one professional Australian football club participated in this study. Each week during the competitive season (22 weeks), players self-reported their...

Objectives The purpose of this study was to investigate the effectiveness of an isometric neck strengthening program to improve isometric neck strength in elite women's football-code athletes. Design Randomised controlled trial. Method Elite female soccer (n = 10) and Australian football (n = 30) players were randomised into either a control (n =...

Ballistic motor training induces plasticity changes and imparts a cross-transfer effect. However, whether there are age-related differences in these changes remain unclear. Thus, the purpose of this study was to perform a meta-analysis to determine the corticospinal responses and cross-transfer of motor performance following ballistic motor trainin...

Measurement of the adverse outcomes of repeated head trauma in contact sport athletes is often achieved using tests where the comparator is the score or the accuracy obtained. While it is expected that ex-athletes would perform worse than controls, previous studies have shown inconsistent results. Here we have attempted to address these inconsisten...

Chronic traumatic encephalopathy (CTE) is a neurodegenerative tauopathy caused by repetitive head injury. Although it has chiefly been studied in contact sport participants, anyone who experiences repetitive head injury is at risk of CTE. It is associated with a range of neuro-psychological problems, ranging from mood and behavioural symptoms to co...

Background Concussion in sport is an ongoing global concern. The head injury assessment (HIA) by the field of play is acknowledged as the first step in recognising and identifying concussion. While previous systematic literature reviews have evaluated the sensitivity of sideline screening tools and assessment protocols, no systematic review has eva...

Objective: To document baseline King-Devick (K-D) oculomotor function scores for male and female participants aged between 4 and 20 years old. Methods: Utilising a cross section of schools, rugby clubs and gymnastic clubs, 1936 participants (1300 male, 636 female) completed the spiral-bound K-D test for the identification of disturbed oculomotor...

Background : Management of concussion remains a serious issue for professional sports, particularly with the growing knowledge on the consequences of repetitive concussion. One primary concern is the subjective assessment of recovery that dictates the time until a concussed athlete is returned to competition. In response to this concern, the Austra...

The corticospinal responses to high-intensity and low-intensity strength-training of the upper limb are modulated in an intensity-dependent manner. Whether an intensity-dependent threshold occurs following acute strength training of the knee extensors (KE) remains unclear. We assessed the corticospinal responses following high-intensity (85% of max...

Five international consensus statements on concussion in sports have been published. This commentary argues that there is a strong need for a new approach to them that foregrounds public health expertise and patient-centered guidance. Doing so will help players, parents and practitioners keep perspective about these potentially life-altering injuri...

Five international consensus statements on concussion in sports have been published. This commentary argues that there is a strong need for a new approach to them that foregrounds public health expertise and patient-centered guidance. Doing so will help players, parents, and practitio- ners keep perspective about these potentially life- altering in...

The issue of concussion in sport continues to be discussed widely in the community as current and retired players reveal personal experiences, and concerns, about the long-term sequelae of their concussive injuries. This is the first study to examine evolving attitudes and beliefs towards concussion in sport by comparing data in an Australian exerc...

Purpose of Review Mild traumatic brain injury (mTBI) is a continuing healthcare concern worldwide contributing to significant cognitive and neurological impairment, consequently affecting activities of daily living. While mTBI recovery is becoming well studied, there are no interventions to reduce the known impairments of mTBI. Omega-3 fatty acids...

BACKGROUND: Previous studies suggest that cross-education of strength may be modulated by increased corticospinal excitability of the ipsilateral primary motor cortex (M1) due to cross-activation. However, no study has examined the influence of bilateral TDCS of both M1 and how it affects corticospinal excitability, cross-activation and cross-educa...

Sports-related concussion (SRC) is a complex and heterogeneous injury with psychological, cognitive and functional consequences. Advances in diffusion magnetic resonance imaging (dMRI) allow sensitive measurement of white matter pathology post-SRC and may provide insight into injury and recovery. We systematically reviewed and meta-analyzed the lit...

Chronic traumatic encephalopathy (CTE) has been identified at post-mortem in Australian football codes players. Detailed and objective clinical and radiological characterization of patients at-risk of sporting and non-sporting repetitive concussive and subconcussive traumatic brain injury (RC/SCI) is important to our understanding of traumatic ence...

Emerging research has studied in-game metrics of athletes after returning from concussion injury in an attempt to determine if performance is compromised. The aim of this meta- analysis was to quantify performance metrics in professional athletes prior to and following recovery from concussion. We conducted systematic literature searches in databas...

Background Management of concussion remains a serious issue for professional sports, particularly with the growing knowledge on the consequences of repetitive concussion. One primary concern is the subjective assessment of recovery that dictates the time until a concussed athlete is returned to competition. In response to this concern, the Australi...

Emerging evidence of brain injury on risk of neurodegenerative diseases such as Alzheimer’s disease (AD) and chronic traumatic encephalopathy (CTE) have resulted in interest in therapeutic potential of omega-3 fatty acids (n-3FA). We conducted a systematic review of n-3FA therapeutic efficacy for ageing adults at risk of AD/CTE following a history...

The objective of this systematic literature review was to evaluate the evidence regarding the development of neck strength in reducing concussion and cervical spine injuries in adult amateur and professional sport populations. PubMed, CINAHL, Science Direct, and Web of Science databases were searched systematically. The criteria for inclusion in th...

Considerable attention has focused on the risks of contact sports like rugby union, yet the benefits, rewards and opportunities have received less robust analysis. It is for that reason, Griffin et al.'s recent scoping review is a welcome preliminary contribution to our understanding of risk in rugby. There are, however, some concerns that deserve...

Purpose: Cross-education (CE) increases strength of both the trained and untrained limb, with emerging evidence, suggesting CE could be used to attenuate muscle strength and thickness following periods of limb immobilization. This study examined the available evidence for the clinical efficacy of CE to attenuate muscle strength, thickness and neura...

Elite competitive sport is linked with a unique collection of stressors distinct from the general population. While there have been advancements in understanding the role that stressors play within the elite sporting environment, uncertainty still exists around a clear process for measuring stressors, and their specific relationship to injury. A nu...

A single bout of aerobic exercise (AE) may induce changes in the excitability of the intracortical circuits of the primary motor cortex (M1). Similar to noninvasive brain stimulation techniques, such as transcranial direct current stimulation, AE could be used as a priming technique to facilitate motor learning. This review examined the effect of A...

Introductory chapter to the book explaining the evolving links between neuroscience and exercise science.

Understanding motor control is through learning the macro and the micro arrangement of the nervous system. In this chapter, we will focus on the macro: structural, functional and hierarchical organisation of movement. In chapters four and five, we will discuss how motor control occurs through neuromodulation and neuroplastic changes. The study of n...