Mark Waldron

Swansea University | SWAN · Research Centre in Applied Sports, Technology, Exercise and Medicine "A-STEM"

Purpose: The efficacy of isolated and relative performance indicators (PIs) has been compared in rugby union; the latter more effective at discerning match outcomes. However, this methodology has not been applied in women's rugby. The aim of this study was to identify PIs that maximize prediction accuracy of match outcome, from isolated and relati...

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...

We determined the effects of topically applied i) isolated menthol cream, ii) menthol and capsaicin co-application or iii) placebo cream on exercise tolerance, thermal perception, pain, attentional focus and thermoregulation during exercise in the heat. Ten participants cycled at 70% maximal power output until exhaustion in 35°C and 20% relative hu...

The factors explaining variance in thermoneutral maximal oxygen uptake (V˙O2max) adaptation to heat acclimation (HA) were evaluated, with consideration of HA programme parameters, biophysical variables and thermo-physiological responses. Seventy-one participants consented to perform iso-intensity training (range: 45%-55% V˙O2max) in the heat (range...

Objective: Inter-day reliability of sweat measurements, including the absorbent patch and modified iodine-paper techniques, at rest and exercise were evaluated. We further evaluated the effect of iodine paper size and the method of establishing sweat gland activation (sweat gland counting or surface area covered) on reliability. Furthermore, the r...

Objectives The aims of this study were to: i) identify performance indicators (PIs) associated with match outcomes in the United Rugby Championship to; ii) compare efficacy of isolated data and data relative to opposition in predicting match outcome; and iii) investigate whether reduced PI statistical models can reproduce predictive accuracy. Meth...

Biomarkers relating to player "stress balance," immunological (ie, immunoglobulin-A), and hormonal (ie, testosterone and cortisol [T:C]) status are now commonly used in football. This article is our critical review of the scientific literature relating to the response of these measures to player load and their relationships with player health. The...

This study investigated whether anthropometric and physical abilities explained variance in match collision performance among international female rugby union players. Physical performance and anthropometric data for fifty-one international female rugby union players, and collision actions categorised as “effort” or “performance” variables, from 20...

Heat-induced hypo-hydration (hyperosmotic hypovolemia) can reduce prolonged skeletal muscle performance; however, the mechanisms are less well understood and the reported effects on all aspects of neuromuscular function and brief maximal contractions are inconsistent. Historically, a 4-6% reduction of body mass has not been considered to impair mus...

This study assessed the influence of environmental factors, air travel, and epoch estimation method on locomotor demands of international men’s rugby sevens match-play. Eighteen men’s rugby sevens players wore 10 Hz Global Positioning Systems (STATsport) during 52 international matches over nine global tournaments (418 observations). Whole-match av...

Grainger, A, Heffernan, S, Waldrom, M, and Sawczuk, T. Autonomic nervous system indices of player readiness during elite-level rugby union game-week microcycles. J Strength Cond Res XX(X): 000-000, 2022-Elite-level rugby union (RU) is a high-intensity contact sport that involves large training and match volumes across a season, which can lead to po...

Purpose: To examine the effect of fast- versus slow-speed eccentric-muscle-action resistance training on lower-body strength, vertical jump height, sprint speed, and change-of-direction performance in elite soccer players during a competitive season. Methods: Twenty-two elite soccer players, from a single team, were randomly assigned to groups t...

Objective: There is a high incidence of concussion and frequent utilization of rapid weight loss (RWL) methods among combat sport athletes, yet the apparent similarity in symptoms experienced as a result of a concussion or RWL has not been investigated. This study surveyed combat sports athletes to investigate the differences in symptom onset and...

INTRODUCTION: Repeated ischemic preconditioning (IPC) can improve muscle and pulmonary oxygen on-kinetics, blood flow, and exercise efficiency, but these effects have not been investigated in severe hypoxia. The aim of the current study was to evaluate the effects of 7 d of IPC on resting and exercising muscle and cardio-pulmonary responses to seve...

Longitudinal changes in anthropometric and physical performance characteristics of International female rugby union players were evaluated across 5-seasons, according to field position. Sixty-eight international female rugby union players from a top 2 ranked international team, undertook anthropometric and physical performance measurements across f...

Objectives To compare two modes (general and cricket-specific) of morning priming exercise on afternoon physical and cognitive performance, and subjective readiness to perform in professional male cricketers. Design Randomised, crossover, counterbalanced. Methods On three occasions, 16 professional men’s cricketers completed afternoon tests of co...

Rugby union (RU) is an intermittent team sport, with diverse playing positions, played internationally by both men and women. Considerable scientific attention has been devoted to men’s RU, however despite the growth in the women’s professional game, there is a significant lack of available physiological and normative data. The purpose of the prese...

Within sprint cycling, the ankle's primary role is transferring power generated at the hip and knee. However, a stiffer musculotendinous unit around the ankle may directly contribute to increased performance. The aim of this study was to measure the influence of isometric and plyometric training on ankle stiffness and sprint cycling performance. Fi...

Background The ergogenic effects of dietary supplements on endurance exercise performance are well-established; however, their efficacy in hot environmental conditions has not been systematically evaluated. Objectives (1) To meta-analyse studies investigating the effects of selected dietary supplements on endurance performance and core temperature...

We examined how summated training and match load measures relate to salivary immunological and hormonal profile changes in professional football players. Data were collected from 18 elite-level professional male football players from one English Championship team across a complete 40 wk competitive season. Daily training (micro-technology) and matc...

This is the first study to report the whole match, ball-in-play (BiP), ball-out-of-play (BoP), and Max BiP (worst case scenario phases of play) demands of professional soccer players competing in the English Championship. Effective playing time per soccer game is typically <60 min. When the ball is out of play, players spend time repositioning them...

We evaluated the reliability of an over-ground running three-minute all-out test (3MT) and compared this to traditional multiple-visit testing to determine the critical speed (CS) and distance >CS (D´). Using a novel energetics model during the 3MT, critical power (CP) and work >CP (W´) were also evaluated for reliability and compared to the multip...

Background Heat acclimation and acclimatisation (HA) is typically used to enhance tolerance to the heat, thereby improving performance. HA might also confer a positive adaptation to maximal oxygen consumption ( $$V{\text{O}}_{2\max }$$ V O 2 max ), although this has been historically debated and requires clarification via meta-analysis. Objectives...

Objectives This study aimed to evaluate changes in rugby union physical match characteristics across five seasons of International female competition, according to position and opposition quality. Design & Methods Global positional systems and performance analysis data from 78 female rugby union players (minimum of five international appearances)...

Objectives The aim of this investigation was to determine if acute or repeated applications of ischemic preconditioning (IPC) could enhance the recovery process, following exercise induced muscle damage (EIMD). Design Randomized control trial. Methods Twenty-three healthy males were familiarised with the muscle damaging protocol (five sets of 20...

Purpose: This investigation examined the longitudinal changes and inter-relationships of salivary and self-report monitoring measures across a professional football season. Methods: Measures were collected bi-weekly from 18 senior professional male players across a six-week pre-season and eight five-week in-season mesocycles and analysed using a...

This study evaluated the contribution of physiological data collected during laboratory testing in predicting race performances of trained junior middle-distance track (TK) and cross-country (XC) athletes. Participants performed a submaximal incremental ramp test, followed by an incremental test to exhaustion in a laboratory, with the results used...

We investigated the effects of taurine supplementation on cycling time to exhaustion in cold conditions. Eleven males cycled to exhaustion at a power output equivalent to the mid-point between ventilatory threshold and maximum aerobic power following 15-min rest in the cold (apparent temperature of ∼ 4°C; air flow of 4.17 m s-1). Two hours before,...

Context: Ankle dorsiflexion range of motion (DF ROM) has been associated with a number of kinematic and kinetic variables associated with landing performance that increase injury risk. However, whether exercise-induced fatigue exacerbates compensatory strategies has not yet been established. Objectives: i) explore differences in landing performance...

The aims of this study were to i) compare a foot-mounted inertial system (PlayerMaker™) to three commercially available Global Positioning Systems (GPS) for measurement of velocity-based metrics during team sport movements and ii) evaluate the inter-unit reliability of the PlayerMaker™. Twelve soccer players completed a soccer simulation, whilst we...

Aims This study investigated the efficacy of l-menthol mouth-rinsing on thermal sensation and perceived effort in females and males, using a fixed-rating of perceived exertion (RPE) exercise protocol in a hot environment. Methods Twenty-two participants (eleven females, eleven males) completed two trials using a fixed-RPE protocol at an exercise i...

IntroductionMenthol topical application and mouth rinsing are ergogenic in hot environments, improving performance and perception, with differing effects on body temperature regulation. Consequently, athletes and federations are beginning to explore the possible benefits to elite sport performance for the Tokyo 2021 Olympics, which will take place...

This investigation compared the competitive demands, as quantified by game distribution and density characteristics, of the major British and European football leagues. Pairwise comparisons between leagues revealed that English Championship teams played more total games, two game weeks and had a higher game density than teams from all other leagues...

This investigation examined match play physical performance across a professional football season using a multicamera computerized tracking system. A linear mixed-effects model, controlling for situational and contextual variables, identified decreases in team average total distance (TD): season quarter 1 (Q1) (11,047 m) > season quarter 2 (Q2) (10...

The different architectural adaptations and the regional changes that occur with eccentric (ECC) vs concentric (CON) muscle actions are not fully understood. The purpose was to investigate regional changes in vastus lateralis muscle (VL) after ECC and CON training. Sixteen males (23 ± 3 years) performed ECC or CON training twice weekly over 5 weeks...

An energy-based approach to quantifying the mechanical demands of overground, constant velocity and/or intermittent running patterns is presented. Total mechanical work done (Wtotal ) is determined from the sum of the four sub components: work done to accelerate the centre of mass horizontally (Whor ), vertically (Wvert ), to overcome air resistanc...

The effectiveness of 8-week force-velocity optimised training was assessed in highly trained professional rugby league athletes. Players (age 24 ± 3 years; body mass 94.9 ± 21.6 kg; height 181.3 ± 6.0 cm) were strength-matched and assigned to a force-velocity optimised group (OP; n = 15) or a general strength-power group (GP; n = 14). Tests include...

Context: Neuromuscular electrical stimulation (NMES) combined with blood flow restriction (BFR) has been shown to improve muscular strength and size better than NMES alone. However, previous studies used varied methodologies not recommended by previous NMES or BFR research. Objective: The present study investigated the acute effects of NMES comb...

The purpose of this study was to evaluate changes in markers of endocrine, immune and mood status among Mixed Martial Arts (MMA) athletes during different stages of fight preparation camps. Six professional MMA athletes were observed across the final five weeks (W4 – W0); including the final seven days (D6 – D0) of fight camp, and were tested for s...

This investigation examined the effect of prior workload on high-intensity football match performance. Player load variables were recorded using a global positioning system and converted into composite variables: rolling season accumulated load (AL), exponentially weighted moving average acute, chronic and acute:chronic workload ratio (A:C). Match-...

Background: Fractures are common in physically active populations and genetic differences may mediate injury risk. Objective: To meta-analyse the pooled results of candidate gene association studies with non-osteoporotic fracture risk in physically active humans. Methods: Systematic searching of databases returned 11 eligible studies published in E...

This study examined the effects of a 4-week ankle-mobility intervention on landing mechanics. Twenty participants with restricted ankle dorsiflexion range of motion (DF ROM) were allocated to either a strength training only (n = 9) or a strength training and ankle mobility program (n = 11). Participants performed a weight-bearing lunge test and bil...

Ankle dorsiflexion range of motion (DF ROM) restriction has been shown to influence negatively influence the performance of functional activities in healthy populations. Limitations in ankle DF ROM can be caused by a lack of extensibility in myofascial tissues surrounding the ankle joint or disruption in ankle joint arthrokinematics. A variety of e...

The aim of this study was to determine the effect of five days dietary nitrate (NO3⁻) consumption on exercise tolerance and thermoregulation during cycling in hot, dry conditions. In a double-blind, randomised crossover design, 11 healthy males participated in an exercise tolerance test (Tlim) in the heat (35°C, 28% relative humidity), cycling abov...

Background: The identification of asymmetrical inter-limb ankle dorsiflexion range of motion (DF ROM) has the potential to influence the course of treatment during the rehabilitation process, with limitations in ankle DF ROM potentially increasing injury risk. However, reliability for identifying ankle DF ROM asymmetries has not yet been establishe...

Background: Spastic cerebral palsy (CP) is characterized by muscle weakness owing, in part, to a blunted muscle protein synthetic response. This might be normalized by long-term leucine supplementation. Objectives: The study assessed the effects of 10 wk leucine supplementation in adolescents and adults with CP. Methods: The study was a single...

The aim of this study was to establish the within-session reliability for two-dimensional (2D) video analysis of sagittal- and frontal-plane measures during bilateral drop-landing tasks. Thirty-nine recreational athletes (22 men, 17 women, age = 22 ± 4 years, height = 1.74 ± 0.15 m, body mass 70.2 ± 15.1 kg) performed five bilateral drop-landings f...

Purpose We compared a new locomotor-specific model to track the expenditure and reconstitution of work done above critical power (W´) and balance of W´ (W´BAL) by modelling flat over-ground power during exhaustive intermittent running. Method Nine male participants completed a ramp test, 3-min all-out test and the 30–15 intermittent fitness test (...

Strength and Conditioning (S&C) coaches must possess a skillset that allows them to assess the physical preparedness of their athletes. This requires the assessment of numerous physical qualities, with testing procedures that produce objective data that is both reliable and valid. Traditionally, assessments for mobility have necessitated palpatory...

Objectives: To profile the distances covered during international women's rugby union match-play and assess the duration-specific worst-case scenario locomotor demands over 60-s to 600-s epochs, whilst comparing the values determined by fixed epoch (FIXED) versus rolling average (ROLL) methods of worst-case scenario estimation and assessing positi...

Game Distribution and Density Differ between the Major British and European Professional Football Leagues MATT SPRINGHAM1, 2*, MARK WALDRON1, 3, DARREN BURGESS4 & ROBERT U. NEWTON2 1 Faculty of Sport, Health and Applied Science, St Marys University, London, UK 2 School of Medical and Health Sciences, Edith Cowan University, Joondalup, AU 3 School...

This study investigated the effects of acute oral taurine ingestion on: (1) the power–time relationship using the 3-min all-out test (3MAOT); (2) time to exhaustion (TTE) 5% > critical power (CP) and (3) the estimated time to complete (Tlim) a range of fixed target intensities. Twelve males completed a baseline 3MAOT test on a cycle ergometer. Foll...

Purpose This study investigated the effects of a 10-day heat acclimation (HA) programme on the time course of changes in thermoneutral maximal oxygen uptake (\(\dot{V}\)O2max) during and up to 10 days post-HA. Methods Twenty-two male cyclists were assigned to a HA or control (Con) training group following baseline ramp tests of thermoneutral \(\do...

The validity of the TritonWear ® device to measure swimming performance was investigated, with a pre-determined analytical goal of 6%. Twenty youth swimmers completed a 100 m swim in a 25 m pool, swimming breaststroke or freestyle wearing the TritonWear ® device, whilst being filmed above and below water with three cameras. 95% limits of agreement...

Ischaemic preconditioning (IPC) has emerged as a potential non-invasive ergogenic aid to enhance exercise performance. Repeated application of IPC has demonstrated clinical efficacy, therefore our aims were to investigate its effect on endurance cycling performance and muscle efficiency. Twenty participants undertook 7-d repeated bilateral lower li...

Jeffries, O, Simmons, R, Patterson, SD, and Waldron, M. Functional threshold power is not equivalent to lactate parameters in trained cyclists. J Strength Cond Res XX(X): 000-000, 2019-Functional threshold power (FTP) is derived from a maximal self-paced 20-minute cycling time trial whereby the average power output is scaled by 95%. However, the ph...

Purpose The purpose of this study was to determine the primary cues regulating perceived effort and exercise performance using a fixed-RPE protocol in severe and moderate hypoxia. Methods Eight male participants (26 ± 6 years, 76.3 ± 8.6 kg, 178.5 ± 3.6 cm, 51.4 ± 8.0 mL kg− 1 min− 1 𝑉˙ V ˙ O2max) completed three exercise trials in environmental...

Limited evidence is available concerning ankle dorsiflexion range of motion (DF ROM) and its relationship with landing performance from varying drop heights. The aim of this investigation was to determine the relationship between ankle DF ROM and both kinetic and kinematic variables measured during bilateral drop-landings from 50%, 100% and 150% of...

Purpose Regulation of power output during cycling encompasses the integration of internal and external demands to maximise performance. However, relatively little is known about variation in power output in response to the external demands of outdoor cycling. We compared mean power output and the magnitude of power output variability and structure...

This study investigated the effects of oral taurine supplementation on cycling time to exhaustion at a fixed-intensity and thermoregulation in the heat. In a double-blind, randomised crossover design, 11 healthy males participated in a time to exhaustion test in the heat (35°C, 40% RH), cycling at the power output associated with ventilatory thresh...

Objectives Menthol is an organic compound with non-thermal cooling properties that has been shown to relieve thermal strain associated with exercise in the heat; however, its effects on performance have not been systematically analysed. The aims were to determine the effects of menthol applied (1) internally and (2) externally on exercise performan...

Purpose This study investigated the effects of l-menthol mouth rinse and ice slurry ingestion on time to exhaustion, when administered at the latter stages (~ 85%) of baseline exercise duration in the heat (35 °C). Method Ten male participants performed four time to exhaustion (TTE) trials on a cycle ergometer at 70% Wmax. In a randomized crossove...

Madison, G, Patterson, SD, Read, P, Howe, L, and Waldron, M. Effects of small-sided game variation on changes in hamstring strength. J Strength Cond Res 33(3): 839-845, 2019-Small-sided games (SSGs) are commonly used by soccer practitioners to condition players. This form of exercise can result in fatigue, potentially exposing the muscle to injury...

The purpose of this investigation was to establish the within-session reliability for peak vertical ground reaction force (vGRF), time to peak vGRF, and loading rate, both unilaterally and bilaterally, during a drop-landing task as well as the reliability of inter-limb asymmetry in peak vGRF. Twenty-two men (age = 22 ± 4 years; height = 180.4 ± 6.1...

Purpose: To firstly, assess changes in neuromuscular function via alterations in the countermovement jump strategy, after training and two forms of competition. Secondly, to compare the relationship between workloads and fatigue in seam bowlers and non-seam bowlers. Methods: Twenty-two professional cricketers' neuromuscular function was assessed...

The purpose of this investigation was to assess the relationship between asymmetries in ankle dorsiflexion ROM and kinetic variables associated with bilateral drop-landing performance.

Uddin, N, Jeffries, O, Read, P, Howe, L, Patterson, S, and Waldron, M. Physiological responses to linear and nonlinear soccer-specific match simulations and their effects on lower-limb muscle fatigue. J Strength Cond Res XX(X): 000-000, 2018-The aims of this study were to: (a) investigate the effects of linear and nonlinear soccer simulations on lo...