Kim Hébert-Losier

• PT, PhD
• Professor (Full) at University of Waikato

The calf raise test (CRT) is commonly used to assess triceps surae muscle-tendon unit function. Often, a metronome set to 60 beats/min (30 repetitions/min) is used to set the cadence of calf raise repetitions, but studies report using cadences ranging from 30 to 120 beats/min. We investigated the effect of cadence on CRT outcomes, accounting for th...

Developing event-specific strength is necessary for optimising throwing performance. Currently, the movement patterns and transferability of pullover exercise to javelin throw performance are unknown. This study assessed the electromyography (EMG) signals during pullover exercise variants, and examined whether maximum strength related to release ve...

Aims: The calf raise test (CRT) assesses plantarflexor strength and endurance, but normative data for children are scarce. Furthermore, contradictions exist on which factors are associated with total repetitions, with repetitions being the only metric considered. We quantified three of the main CRT outcomes (repetitions, total work, and peak heigh...

ABSTRACT: Despite the importance of strength and power in rugby skills and match outcomes, there exists a noticeable gap in the measurement consistency and estimation of a true change of typical assessments designed to assess these qualities. To address this gap, we investigated the between-session reliability, interrelationships, and minimal detec...

Background Musculoskeletal pain while running is a concern to women during pregnancy and can lead to running cessation. To support women who wish to run during pregnancy, it is essential to understand the sites, severities and personal risk factors associated with musculoskeletal pain. Objective The aim was to investigate prevalence and risk facto...

Introduction. Strength training at slow tempos (longer time under tension) provides additional mechanical stimuli that may allow for optimal strength development. This study investigated the effects of 4 weeks of strength training emphasising either long-eccentric or long-concentric duration on strength, power, and speed development. Methods. Sixte...

Introduction. Strength training at slow tempos (longer time under tension) provides additional mechanical stimuli that may allow for optimal strength development. This study investigated the effects of 4 weeks of strength training emphasising either long-eccentric or long-concentric duration on strength, power, and speed development. Methods. Sixte...

Background Assessing individuals in their own athletic footwear in clinics is common, but can affect movement, performance, and clinical measures. Purpose The aim was to compare overall Landing Error Scoring System (LESS) scores, injury risk categorization, specific LESS errors, and jump heights between habitual athletic footwear and barefoot cond...

Background: The calf raise test (CRT) is commonly administered without a device in clinics to measure triceps surae muscle function. To standardise and objectively quantify outcomes, researchers use research-grade or customised CRT devices. To incorporate evidence-based practice and apply testing devices effectively in clinics, it is essential to...

Objectives.-Concussion is the most prevalent injury in Rugby Union. Isometric neck strength tests have been used in Rugby Union to screen for modifiable injury risk factors. Several methods and variations in protocol exist for neck strength tests, including performing these tests in the 'make' or 'break' fashion. We aimed to compare these two metho...

We compared the effects of two 8-week concurrent strength and endurance trainings (CSETs) on running economy (RE) and running biomechanics, and we explored whether the effects on running biomechanics were mediated by responder status [high vs low responder based on -2.6% change in RE]. Thirty-one male recreational runners were randomly assigned to...

Running shoes are often considered essential to participate in running. Runners may look for recommendations from friends, specialty running stores, and healthcare professionals when selecting shoes. Despite the existence of shoe prescription guidelines, these recommendations are often not evidence-based or designed with runners’ preferences in min...

Introduction The (traditionally influenced) consumption of kava (Piper methysticum) has been associated with increased body sway, raising concerns about fall risk. However, studies typically utilise pill-styled kava extracts with a lack of understanding regarding experienced naturalistic kava drinkers. This pilot study investigated the effects of n...

Hamstring strain injuries are one of the most common injuries in Rugby Union players, representing up to 15% of all sustained injuries. The Nordic eccentric hamstring test assesses the maximal hamstring eccentric strength and imbalances between limbs. Asymmetries and deficits in hamstring strength between legs are commonly assessed and used as scre...

Background: Calf raise test (CRT) is used in rehabilitation and sports medicine to evaluate calf muscle function. The Calf Raise application (CRapp) uses computer-vision algorithms to objectively measure CRT outcomes and replicate laboratory-based metrics that are difficult to measure clinically. Objective: To validate the CRapp by examining its...

Introduction: Anterior cruciate ligament (ACL) injuries are a common and severe knee injury associated with sport participation and can involve arthroscopic surgery. Clinical tests to assess the neuromuscular function of the affected limb compared to the non-affected limb expressed by limb symmetry indices, typically inform for Return-to-Sport (RTS...

Statement of the Problem: Generalized joint hypermobility is an important risk factor for knee injuries, including to the anterior cruciate ligament (ACL). A recent framework for the classification of joint hypermobility [1] suggests dividing hypermobile individuals into three groups: asymptomatic, symptomatic and individuals with a well-defined sy...

Objectives Compare overall Landing Error Scoring System (LESS) scores, risk categorisation, specific LESS errors, and double-leg jump-landing jump heights between overhead goal and no goal conditions. Design Randomised cross-over. Setting Laboratory. Participants 76 (51% male). Main outcome measures Participants landed from a 30-cm box to 50% o...

Background: Running injuries are predominantly located at the lower limbs, specifically the foot, ankle, lower leg and knee within non-pregnant populations (1). During pregnancy, to compensate for physical changes in body mass distribution, gait alterations have potential to influence the types of pain and discomfort experienced (2). To support hea...

This review aimed to synthesise the methods for assessing and reporting footwear characteristics among studies evaluating the effect of footwear on running biomechanics. Electronic searches of Scopus®, EBSCO, PubMed®, ScienceDirect®, and Web of Science® were performed to identify original research articles of the effect of running footwear on runni...

Purpose: To investigate differences in athletes' knowledge, beliefs, and training practices during COVID-19 lockdowns with reference to sport classification and sex. This work extends an initial descriptive evaluation focusing on athlete classification. Methods: Athletes (12,526; 66% male; 142 countries) completed an online survey (May-July 2020...

We examined the validity and reliability of biomechanical outcomes extracted using the Calf Raise application of three calf muscle tests. We then established normative calf muscle function values for male rugby union players accounting for rugby-related factors (position, level) alone and together with clinical factors (age, leg dominance, BMI, pre...

Evaluating the relationships between physical-test and match performance in team sports could be useful for training prescription and athlete evaluation. Here we investigated these relationships in women’s Rugby Sevens. Thirty provincial-representative players performed Bronco-fitness, countermovement-jump, acceleration, speed, and strength tests w...

Advancements in running shoe technology over the last 5 years have sparked controversy in athletics as linked with clear running economy and performance enhancements. Early debates mainly surrounded ‘super shoes’ in long-distance running, but more recently, the controversy has filtered through to sprint and middle-distance running with the emergenc...

Introduction Falling is associated with adverse effects on the health of older people. The majority of research into falls among older people has focused on prevention, with less attention to ‘how to fall safely’. Previous research suggests that motor analogies can be used to promote safe landing by young adults; however, the efficacy of this techn...

Shank rotation is associated with increased risk in lower limb injuries of weight-bearing sport activity. Straight-line running injury prevention research proposes a 'bottom-up' approach to minimising injury risk to the knee. This prophylactic recommendation is due to the observed distal-proximal coupling relationship between rearfoot and shank rot...

Duty factor (DF) and step frequency (SF) are key running pattern determinants. However, running patterns may change with speed if DF and SF changes are inconsistent across speeds. We examined whether the relative positioning of runners was consistent: 1) across five running speeds (10-18 km/h) for four temporal variables [DF, SF, and their subcompo...

Purpose: To investigate differences in athletes' knowledge, beliefs, and training practices during COVID-19 lockdowns with reference to sport classification and sex. This work extends an initial descriptive evaluation focusing on athlete classification. Methods: Athletes (12,526; 66% male; 142 countries) completed an online survey (May-July 2020) a...

We conducted an exploratory analysis to compare running kinematics of 16 male recreational runners wearing Nike Vaporfly 4% (VP4), Saucony Endorphin racing flat (FLAT), and their habitual (OWN) footwear. We also explored potential relationships between kinematic and physiological changes. Runners (age: 33 ± 12 y, V˙ O2peak: 55.2 ± 4.3 ml · kg-1·min...

Despite the wealth of research on injury prevention and biomechanical risk factors for running related injuries, their incidence remains high. It was suggested that injury prevention and reconditioning strategies should consider spontaneous running forms in a more holistic view and not only the injury location or specific biomechanical patterns. Th...

Running biomechanics and ethnicity can influence running economy (RE), which is a critical factor of running performance. Our aim was to compare RE of South East Asian (SEA) and non-South East Asian (non-SEA) runners at several endurance running speeds (10–14 km/h) matched for on-road racing performance and sex. Secondly, we explored anthropometric...

Concussion is the most common injury in professional Rugby Union (RU) players, with increasing incidence and severity each year. Strengthening the neck is an intervention used to decrease concussion incidence and severity, which can only be proven effective if strength neck measures are reliable. We conducted a repeated-measures reliability study w...

Purpose: Explore whether dorsiflexion range of motion (ROM) influences cutting kinematics. Methods: Dorsiflexion ROM was measured in 42 individuals using the weight-bearing lunge test (WBLT). Unanticipated cutting kinematics were collected at initial contact (IC) and between IC and maximum knee flexion using three-dimensional motion and inertial m...

Background: The Landing Error Scoring System (LESS) identifies participants displaying potentially high-risk movement patterns during a double-leg jump-landing (DLJL) task. However, the DLJL has been criticized for not reflecting injury-prone situations in sport. The biomechanics and perceived difficulty of a rotated single-leg jump-landing (SLJLro...

Purpose: The subjective Volodalen® score (V®score) and the objective duty factor metric can both assess global running patterns. The authors aimed to investigate the relation between running economy (RE) at endurance running speeds and the global running pattern quantified using both subjective and objective measures. Methods: RE and 3-dimension...

Carbohydrate mouth-rinsing has been reported to benefit endurance performance in athletes intermittently fasting; however, in the fasted state, the effects of combined caffeine and carbohydrate (CAF-CHO) mouth-rinsing on sprint-endurance performance are unknown. We determined the effects of CAF-CHO mouth-rinsing on kinetics, kinematics, and percept...

Purpose: Falls are a risk factor for mortality in older adults. Light interventions can improve cognitive function and performance in motor tasks, but the potential impact on postural control with relevance to falling is unknown. This study aimed to examine the effect of light on postural control, motor coordination, and cognitive functioning. Meth...

Limited research exists on the effects of menstrual phase on athletic performance in team sport athletes. In this case-study we investigated the potential effect of menstrual cycle phase on several physical qualities in rugby athletes. Four eumenorrhoeic female rugby athletes completed a battery of physical tests weekly for 5-9 weeks, including 10-...

Objectives: Explore training-related knowledge, beliefs and practices of athletes and the influence of COVID-19-related lockdowns. Methods: Athletes [n = 12,526 classified: world-class (13%), international (21%), national (36%), state (24%), and recreational (6%)] completed an online survey (50 d; 17th May to 5th July 2020) exploring their trainin...

Background: Hamstring strain injuries are one of the most common injuries in Rugby Union, representing up to 15% of all injuries sustained. We aimed to systematically review and summarize the scientific literature that addressed hamstring strain injury incidence, risk factors, injury prevention or strengthening strategies, and strength or asymmetr...

Objective: Current return-to-sport decisions are primarily based on elapsed time since surgery or injury and strength measures. Given data that show rates of successful return to competitive sport at around 55%, there is strong rationale for adopting tools that will better inform return to sport decisions. The authors’ objective was to assess react...

Objective: Current return-to-sport decisions are primarily based on elapsed time since surgery or injury and strength measures. Given data that show rates of successful return to competitive sport at around 55%, there is strong rationale for adopting tools that will better inform return to sport decisions. The authors' objective was to assess reac...

PURPOSE: Stability and precision of a measurement are necessary for practitioners to detect meaningful changes in performance. We investigated between-session reliability and the minimal detectable change (MDC) in strength and power measures commonly assessed in team sports. METHODS: A sample of sixteen (n=16) Malaysian national rugby 7s players (h...

Context The Landing Error Scoring System (LESS) screens for risk of noncontact anterior cruciate ligament injury. The LESS requires individuals to jump forward from a 30-cm box to a distance of 50% of their body height. However, different landing distances have been cited in the scientific literature. Objective To examine whether landing distance...

Background The Targeted Interventions for Patellofemoral Pain studies (TIPPs) have identified three subgroups exist in UK and Turkish patellofemoral pain (PFP) populations: Strong; Weak and Tight; and Weak and Pronated, based on six clinical assessments. The thresholds used to develop the subgrouping algorithms were based on normative values source...

The relationships between performance in the 1.2 km shuttle test (Bronco) with the Multistage Shuttle Run Test (MSRT) and Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo IR1) in rugby players were investigated. Additionally, differences in Bronco, MSRT, and Yo-Yo IR1 scores between backs (B) and forwards (F), and rugby codes were assessed. Data fro...

Background Generalized joint hypermobility is an important risk factor for knee injuries, including to the anterior cruciate ligament (ACL). Examining movement patterns specific to hypermobile individuals during sport-specific movements could facilitate development of targeted recommendations and injury prevention programs for this population. Hyp...

High-level golfers use various warm-up strategies to enhance clubhead and ball speed, including weighted equipment. We investigated the acute effects of the SuperSpeed Golf™ weighted-club warm-up on clubhead, ball, and swing kinematics, and the persistence of any acute effects in subsequent sets. Twelve competitive golfers (handicap < 3.0) complete...

The Movement Specific Reinvestment Scale (MSRS) measures the propensity for conscious monitoring and control of movement, which can inhibit automated movement processes, potentially causing movement disruption or injury. High injury risk individuals are more likely to make movement errors during jump-landing tasks, and hypermobile individuals prese...

Background: The double-leg jump-landing (DLJL) task is commonly used as a movement screen that can be implemented in large cohorts of athletes. However, it is debatable whether the DLJL is ecologically valid and reflects sporting requirements or injury-prone situations, such as cutting and pivoting. Research question: Which jump-landing movement v...

The incidence and severity of concussion injuries are increasing every year. Scientific evidence indicates that neck strength and girth could play a role in preventing head and neck injuries, or at least mitigating their severity. We aimed to examine the scientific literature addressing neck strength in Rugby Union with a focus on the potential rol...

Purpose We compared running economy (RE) and 3-km time-trial (TT) variables of runners wearing Nike Vaporfly 4% (VP4), Saucony Endorphin lightweight racing flats (FLAT), and their habitual running (OWN) footwear. Methods Eighteen male recreational runners (mean +/− SD, age: 33.5 ± 11.9 year (mean ± standard deviation), peak oxygen uptake (VO2peak)...

Context: The Landing Error Scoring System (LESS) screens for risk of non-contact Anterior Cruciate Ligament injury. The LESS requires individuals to jump forward from a 30-cm box to a distance of 50% of their body height. However, different landing distances have been used in the scientific literature. Objective: To examine whether landing dista...

PurposeThe current study aimed to assess the changes in physical and perceptual markers of health, fitness, and well-being over the first semester of university study in a New Zealand context.Methods In a pre-post longitudinal design, 90 first-year university students (39 females, 51 males, mean ± SD age: 18 ± 2 years) studying in the field of heal...

Objectives: Systematically review the literature addressing age, sex, previous injury, and intervention program as influencing factors of the Landing Error Scoring System (LESS). Design: Systematic review with meta-analysis. Methods: Three databases (PubMed, Web of Science ® , and Scopus ®) were searched on 1 April 2020. Original studies using...

Objective: To examine if the knowledge of scoring criteria and prior performance influence Landing Error Scoring System (LESS) outcomes. Design: Cross-sectional. Setting: Laboratory. Participants: Thirty individuals. Main outcome measures: The LESS was tested at Baseline and one week later under two conditions: Pre and Post information. For the...

Preventing lateral ankle sprain injuries (LAS) in females competing in court sports is a high priority, as an athlete’s risk for re-injury and developing long term dysfunction increases significantly after sustaining an acute LAS. Stability to the ankle joint is passively provided by the joint congruity and ligaments, and actively by the muscles ac...

The prevalence of rearfoot striking is ∼60% in elite marathoners, but ∼90% in North American and European recreational marathoners. Recent data indicate that this prevalence is ∼70% in Asian recreational marathoners. How this prevalence changes throughout the course of a marathon remains undocumented. We filmed 350 runners at the 10 km and 39 km ma...

Background: The Landing Error Scoring System (LESS) identifies movement patterns associated with Anterior Cruciate Ligament (ACL) injury. Hypermobility and knee hyperextension may alter these patterns given that hypermobile individuals present higher injury rates. Methods: Eighty-five individuals were tested using the LESS and Beighton hypermobilit...

Cross-country skiing is a complex endurance sport requiring technical skills, in addition to considerable physiological and tactical abilities. This review aims to identify biomechanical factors that influence the performance of cross-country skiers. Four electronic databases were searched systematically for original articles in peer-reviewed journ...

Objectives To explore whether final Landing Error Scoring System (LESS) scores differ between calculation methods used in literature. Design Cross-sectional. Setting Laboratory. Participants 328 individuals. Main outcome measures LESS scores from 984 drop-jumps were extracted. Final LESS scores were calculated for every participant according to...

The ability to score from placekicks discriminates winning from losing Rugby Union teams. We aimed to identify which biomechanical variables related to successful placekicking in professional Rugby Union players, and use self-organising maps (SOM) to determine whether meaningful sub-groups existed. Three professional placekickers performed 10 kicks...

Context: Sensorimotor, proprioceptive, and neuromuscular programs are critical for the successful rehabilitation of injured athletes, and these decrease reinjury rates. Objective: To investigate the effects of an unexpected disturbance program (UDP) on balance and unilateral strength metrics in athletes with unilateral knee ligament injury. Des...

The purpose of this study was to analyze the validity and reliability of the BEAST™ wearable device to measure movement velocity during the back squat exercise. Eleven national-level female field-hockey players (age: 18.4 ± 1.7 y; back squat 1-RM: 92.7 ± 14.1 kg; height: 158.4 ± 4.6 cm; weight: 54.5 ± 5.5 kg) performed 3 repetitions of the back squ...

When new protocols are developed, there is a requirement to investigate test–retest reliability of measures for valid use and interpretation of data in research and practice. Therefore, the aim of this investigation was to determine the inter-day reliability of the cable put and seated rotation assessment protocols. On three occasions, nine resista...

The Landing Error Scoring System (LESS) is an injury-risk screening tool used in sports; but scoring is time consuming, clinician-dependent, and generally inaccessible outside of elite sports. Our aim is to evidence that LESS scores can be automated using deep-learning-based computer vision combined with machine learning and compare the accuracy of...

Purpose: We compared running economy (RE) and 3-km time-trial (TT) performances of male recreational runners wearing the Nike Vaporfly 4% (NIKE), lightweight racing flats (FLAT), and their habitual footwear (OWN). Methods: Eighteen male recreational runners [age: 33.5 (11.9) y, V̇O2peak: 55.8 (4.4) mL·kg-1·min-1] attended 4 sessions ~7 days apart....

Context The Landing Error Scoring System (LESS) is a clinical tool often used in research and practice to identify athletes presenting high injury-risk biomechanical patterns during a jump-landing task. Objective To systematically review the literature addressing the psychometric properties of the LESS. Data Sources Three electronic databases (Pu...

Introduction: The Landing Error Scoring System (LESS) is a reliable and valid injury risk screening tool used to identify potentially high injury risk movement patterns. These patterns may be altered in participants with hypermobility or knee hyperextension. Method: Eighty-five young active individuals (37 females, 48 males) were tested using LESS...

Introduction: The Nike Vaporfly 4% shoe (NIK) is marketed as a tool that improves running economy and performance. We compared running economy (RE) and 3-km time-trial (TT) performance in recreational runners wearing NIK, habitual (HAB) running shoes, and Saucony racing flats (SAU). Method: Nineteen male runners (age: 32.7±12.0 y) attended 4 sessio...

Since the inclusion of rugby sevens in the 2016 Olympic Games, the popularity of women’s rugby sevens has grown rapidly worldwide. This systematic review aimed to summarize the scientific literature addressing the match demands, anthropometric characteristics, and physical qualities of female rugby sevens athletes, and to highlight differences betw...

Introduction: Limited research exists on the effects of menstrual phase on athletic performance in team sport athletes. This study aimed to investigate the effect of menstrual cycle phase on a number of physical qualities in rugby athletes. Methods: Six eumenorrhoeic female rugby athletes completed a battery of physical tests weekly for 5-9 weeks,...

Background: The Movement Specific Reinvestment Scale (MSRS) measures the propensity for conscious control of movement. Conscious control can inhibit automated movement processes, potentially causing movement disruption or injury. Hypermobile individuals present with poor movement control or clumsiness, and high injury risk individuals make more mov...

Runners were classified using two different methods based on their spontaneous running form: (1) subjectively using the V®score from the Volodalen® scale, leading to terrestrial and aerial groups; and (2) objectively using the duty factor (DF), leading to high (DFhigh) and low (DFlow) DF groups. This study aimed to compare these two classification...

Student engagement is an essential aspect of educational environments, and this is especially true for Science, Technology, Engineering, and Mathematics (STEM) disciplines, where student engagement declines in middle and high school years. Techniques for bolstering student engagement, such as hands-on learning, may be especially effective in the fi...

Background: Centre of pressure (COP), plantar pressure (PP), and plantar-flexion isometric strength (PFisom) are often examined in relation to postural control and gait. Research question: Our aim was to systematically review and quality appraise articles addressing the reliability of COP and PP measures in static stance and PFisom measures. Me...

The biomechanics of the rotational shot put are used to direct coaching to enhance throwing performance. Maximising shot put distance and velocity at the point of release through increasing momentum is of interest to coaches. This narrative review aimed to examine and summarise the critical kinematic variables within each of the six phases of rotat...

It is essential that assessment outcomes are reproducible and comparable between studies to improve healthcare management and science inference. The Landing Error Scoring System (LESS) is a valid and reliable tool used to identify athletes presenting high injury-risk biomechanical patterns [1]. Three drop-jumps are typically assessed; however, sinc...

Close to 90% of recreational runners rearfoot strike in a long-distance road race. This prevalence has been obtained from North American cohorts of runners. The prevalence of rearfoot strikers has not been extensively examined in an Asian population of recreational runners. Therefore, the aim of this study was to determine the prevalence of rearfoo...

Schofield, M, Tinwala, F, Cronin, J, Hébert-Losier, K, and Uthoff, A. Multijoint musculoarticular stiffness derived from a perturbation is highly variable. J Strength Cond Res XX(X): 000-000, 2019-Testing musculoarticular stiffness may provide insights into multijoint elastic properties. Yet, most research has focused on quantifying stiffness, or e...

Public engagement is an important role for the university academic, but is often neglected due to perceived lack of time and prioritized commitments in research and teaching. Yet, public engagement events offer an untapped opportunity for researchers to collect data from members of the general public who arrive on site at university labs. These eng...

Background The number of individuals participating in organised races is increasing, with few studies undertaken in ecologically-valid settings. Running involves cyclical movements and activation of lower-extremity muscles, with fatigue and foot-strike pattern proposed as factors contributing to running-related injuries. Research question Our aim...

A lower duty factor (DF) reflects a greater relative contribution of leg swing versus ground contact time during the running step. Increasing time on the ground has been reported in the scientific literature to both increase and decrease the energy cost (EC) of running, with DF reported to be highly variable in runners. As increasing running speed...

Background: Injury to the anterior cruciate ligament (ACL) is common among young athletes and can impact knee stability and control. Wearing proprioceptive knee braces can improve knee control and may reduce the risk factors associated with injury and re-injury, although the effect of such braces after ACL reconstruction (ACLR) is unclear. Resear...

Background: Muscle adaptations are potentially enhanced through resistance training in elevated environmental temperatures (>30°C) due to upregulated anabolic hormonal responses. Method: Eighteen professional rugby union athletes performed a 3-week resistance training intervention where they were randomly allocated into 2 groups: HEAT (n = 8) with...