Thomas Dos'Santos

Manchester Metropolitan University | MMU · Department of Exercise and Sport Science

Side-step cutting is an action associated with non-contact anterior cruciate ligament (ACL) injury with a plethora of negative economical, health, and psychological implications. Although ACL injury risk factors are multifactorial, biomechanical and neuromuscular deficits which contribute to “high-risk” and aberrant movement patterns are linked to...

Background Most cutting biomechanical studies investigate performance and knee joint load determinants independently. This is surprising because cutting is an important action linked to performance and non-contact anterior cruciate ligament (ACL) injuries. The aim of this study was to investigate the relationship between cutting biomechanics and cu...

Dos'Santos, T, Thomas, C, Comfort, P, and Jones, PA. Biomechanical effects of a 6-week change of direction speed and technique modification intervention: implications for change of direction side step performance. J Strength Cond Res XX(X): 000-000, 2020-The aim of this study was to evaluate the biomechanical effects of change of direction (COD) sp...

The investigation of inter-limb asymmetries has increased in recent years, with practitioners and researchers typically exploring the impact of inter-limb asymmetry on athletic performance, screening inter-limb asymmetry in relation to injury risk, and monitoring of inter-limb asymmetry during injury rehabilitation. A contentious issue regarding th...

Changes of direction (CODs) are key manoeuvres linked to decisive moments in sport and are also key actions associated with lower limb injuries. During sport athletes perform a diverse range of CODs, from various approach velocities and angles, thus the ability to change direction safely and quickly is of great interest. To our knowledge, a compreh...

Background/Objectives: This study investigated the impacts of a 12-week training program on kinetic parameters during landings in non-professional recreational athletes. Methods: Fifty-seven non-elite recreational athletes performed three unilateral-landing trials from a 30 cm high structure on a force platform. The following outcome measures were...

The reverse Nordic is a single joint (knee), controlled open kinetic chain exercise with a predominantly eccentric focus. This review summarizes the reverse Nordic, including exercise benefits, muscles involved, exercise technique, progressions, regressions, and programming strategies. Furthermore, this review outlines how strength and conditioning...

Anterior cruciate ligament (ACL) injuries are complex and influenced by numerous internal and external risk factors that should be considered to effectively mitigate injury and facilitate informed return to sport decision-making. Among these risk factors, movement quality exhibited during sport-specific tasks has been identified as a significant pr...

Background: The similarity between movement patterns and force-vector specificity of training exercises and the target movement will likely result in the greatest transfer of the practiced skills and physical abilities to the intended sports skill performance. Therefore, this review aimed to investigate whether specific adaptations in athletic perf...

Horizontal deceleration is a critical locomotor skill underpinning the many changes of speed and direction performed by athletes in multi-directional sports. Despite its importance there are currently no evidence-based guidelines on how to improve horizontal deceleration ability. Therefore, the aim of this article is to provide practitioners tasked...

Objectives To investigate the physiological and perceptual responses to wearing a dryrobe for rewarming after passive cold-water immersion (CWI). Methods 15 unhabituated healthy Caucasian men (age: 28.9 (5.4) years) attended the laboratory on three occasions and performed passive CWI (14°C) for 30 min followed by 15 min of rewarming wearing either...

Thieschäfer, L, Dos’Santos, T, and Büsch, D. Cutting technique modification: a way to improve movement quality and develop agility in youth? J Strength Cond Res XX(X): 000–000, 2024—High-quality cutting technique is essential for agility development and safer cuttings in adolescent athletes. Certain sidestep techniques and kinematics are characteri...

Adolescence is a fundamental period for female athletes to develop athletic performance, mitigate injury risk, and gain collegiate sport scholarships, but there is also a high incidence of sport-related injuries. Physical profiling and athlete screening can support the individualisation of training programmes; however, there is a lack of data perta...

Dos'Santos, T, Evans, DT, and Read, DB. Validity of the Hawkin dynamics wireless dual force platform system against a piezoelectric laboratory grade system for vertical countermovement jump variables. J Strength Cond Res 38(6): 1144-1148, 2024-The aim of this study was to determine the criterion validity of the Hawkin Dynamics (HD) wireless dual fo...

Objective This study compared neuromuscular control under two fatigue protocols during anticipated and unanticipated change of direction (COD) maneuvers and evaluated their effects on the risk of non-contact ACL injuries. Method Forty-five female soccer players (mean age: 22.22 ± 2.24 years; mean height: 166.24 ± 3.33 cm; mean mass: 59.84 ± 5.03 k...

Background Change of direction (COD) movements are associated with non-contact anterior cruciate ligament (ACL) injuries in multidirectional sports. Females appear at increased risk compared to males, which could be attributable to whole body kinematic strategies and greater multiplanar knee joint loads (KJLs) during COD which can increase ACL load...

Background Qualitative movement screening tools provide a practical method of assessing mechanical patterns associated with potential injury development. Biomechanics play a role in hamstring strain injury and are recommended as a consideration within injury screening and rehabilitation programs. However, no methods are available for the in-field a...

This study aimed to test whether agility and change of direction speed (COD) are independent capacities using the same movement pattern (1) in terms of the completion time and (2) the entropy. Seventeen semi-professional female football players participated in the study. The agility task consisted of a Y-shaped (45° COD) task with three possible ex...

The aim of this study was to identify which kinematic variables are associated with Rugby Union (RU) acceleration sprint performance (step velocity during the first three steps of a 40 m sprint) to create a technical model for RU acceleration sprinting. Nineteen semi-professional male academy RU players were split into fast (top quickest 40 m sprin...

Hamstring strain injuries are one of the most common injuries in sprint-based sports with the mechanism of injury considered the result of an interaction between applied mechanical strain and the capacity of the muscle to tolerate strain. To date, injury prevention and rehabilitation strategies have frequently focused on enhancing the capacity of t...

This study developed a cutting technique modification training program and investigated its effects on cutting performance and movement quality in adolescent American football players. For six weeks, an intervention group (IG) of 11 players participated in 25 min cutting technique modification training sessions integrated into team training twice a...

We aimed to understand whether ankle dorsiflexion range of motion (ROM) and dynamic knee valgus (DKV) kinematic inter-limb asymmetries would be associated with the Lateral Step-Down Test (LSD) in basketball players with chronic ankle instability (CAI), patellofemoral pain (PFP) and healthy controls (HC). An observational cross-sectional study with...

Background: The cutting movement assessment score (CMAS) provides a qualitative assessment of the side-step cutting (S-SC) technique. Previous research has been undertaken primarily by biomechanists experienced with S-SC evaluations. Little is known about the agreement between various sports science and medicine practitioners to ascertain whether t...

The aims of this study were to establish whether directional dominance is displayed during change of direction (COD) tasks across various angles, to determine the angle-variation data for the asymmetry magnitude and direction, and to analyse the relationships in COD performance (completion time and COD deficit) across tasks. Twenty-four young (U-16...

The objective of the study was to evaluate the effectiveness of the Safe Landing (SL), a 6-week technique-modification (TM) programme, on cutting and jump-landing movement quality in football players. In a non-randomized design, 32 male semi-professional football players from two Spanish clubs participated in the study: one served as the control gr...

The aim of this study was to quantify and tactically contextualise (i.e., phase of play and tactical outcome [TO]) sprints (≥7.0 m/s) of an English Premier League (EPL) soccer team during match-play. Videos of 901 sprints (10 matches) were evaluated using the Football Sprint Tactical-Context Classification System. Sprints occurred within a variety...

Background Eumenorrheic women experience cyclic variations in sex hormones attributed to the menstrual cycle (MC) which can impact anterior cruciate ligament (ACL) properties, knee laxity, and neuromuscular function. This systematic review aimed to examine the effects of the MC on ACL neuromuscular and biomechanical injury risk surrogates during dy...

Introduction Sprint running mechanics are thought to be a risk factor for Hamstring Strain Injuries (HSI). However, there is limited evidence to support this association, which may be explained by the lack of in-field assessment methods to evaluate sprint running mechanics.This study aimed to investigate whether a new qualitative screening tool, th...

Introduction Qualitative movement screening tools have been developed across several activities, aiming to identify mechanical patterns associated with potential injury risk. Although sprint running mechanics are thought to influence hamstring strain injuries (HSI), there are currently no field-based screening tools available allowing quick assessm...

Over the years, soccer has become more physically demanding; the number and frequency of high-intensity actions have increased, and these activities are decisive in determining the match outcome. Importantly, the reductionist approach commonly used to analyze high-intensity actions does not contemplate a more contextualized perspective on soccer pe...

The aim of this study was to quantify and contextualize sprinting actions (≥ 7.0 m/s) of English Premier League (EPL) soccer match-play with respect to the movement skills and patterns employed. Video footage (3.2.6, Premier League DVMS, ChyronHego) and raw video-based locomotor coordinates of 901 sprint efforts from 10 matches of an EPL soccer tea...

The authors wish to make the following corrections to this paper [...]

This study aimed to compare the significant turning demands of English Premier League soccer match play relative to playing position using LiDAR technology. Turning data were collected from an English Premier League soccer team (2020-2021 season; 18 fixtures) using a Sportlight® LiDAR tracking system. Turns were tracked during match play, sub-categ...

Objectives To investigate the relationship between the Landing Error Scoring System (LESS) and Cutting Movement Assessment Score (CMAS) to evaluate movement quality, their intra- (INTRAob) and inter-observer (INTERob) reliability, and the comparison between the two drop vertical jump (DVJ) landings (1st and 2nd). Design Cross-sectional. Participa...

Rapid horizontal accelerations and decelerations are crucial events enabling the changes of velocity and direction integral to sports involving random intermittent multi-directional movements. However, relative to horizontal acceleration, there have been considerably fewer scientific investigations into the biomechanical and neuromuscular demands o...

Agility is a complex skill that is influenced by several physical, technical and cognitive factors. In this position stand, we discuss agility as it relates to invasion sports such as the many football codes. An important concept when conceptualising agility is understanding how it is applied on the field or court. Agility is particularly important...

Attacking agility actions, such as side steps, shuffle steps, crossover cutting, split steps, spins, decelerations, and sharp turns, are important maneuvers in invasion team sports, often linked with decisive match winning moments. Generally, the aims of these actions are to (a) evade and create separation from an opponent, (b) generate high exit v...

The purpose of this study was to compare countermovement jump force–time measures between strength-matched male and female soccer players. Males (n = 11) and females (n = 11) were strength-matched via isometric mid-thigh pull testing, whereby peak force values were normalised to body mass. Subjects performed three maximal-effort countermovement jum...

An important element of developing agility with athletes is to evaluate technique in performing actions associated with match play. For practitioners it is important to understand what the key elements of ideal movement technique are to enhance performance. The aim of this article is to revisit an approach to creating a technical framework to help...

Anterior cruciate ligament (ACL) is one of the most concerning injuries for football players. The aim of this review is to investigate the effects of exercise-based interventions targeting at reducing ACL injury rate or mitigating risk factors of ACL injury in adult football players. Following PRISMA guidelines, a systematic search was conducted in...

High-intensity horizontal decelerations occur frequently in team sports and are typically performed to facilitate a reduction in momentum preceding a change of direction manoeuvre or following a sprinting action. The mechanical underpinnings of horizontal deceleration are unique compared to other high-intensity locomotive patterns (e.g., accelerati...

The aim of this was study to examine the inter-task relationships and compare change of direction (COD) biomechanics between different angles (45°, 90°, and 180°). Twenty-seven men performed three COD tasks, whereby lower-limb and trunk kinematics and kinetics were assessed via 3D motion and ground reaction force (GRF) analysis. Key mechanical diff...

Multidirectional speed (MDS) can be defined as the competency and capacity to accelerate, decelerate, change direction, and maintain speed in multiple directions and movements, within the context of sport-specific scenarios."The components of MDS are linear speed, change of direction speed, curvilinear speed, contextual speed, and agility. A MDS de...

The aim of this study was to explore differences in 10 m, 20 m and 40 m sprint times (STs) and initial acceleration kinematic and spatiotemporal step mechanics between Rugby Union (RU) forwards and backs. Nineteen elite male academy RU players (12 forwards; 7 backs; age: 18.0 ± 0.5 years, height: 1.83 ± 0.07 m, mass: 90.3 ± 10.0 kg) were recruited...

This review provides a definition for multidirectional speed (MDS) and evaluates its technical and mechanical underpinnings. This review explores each component of MDS while considering unique aspects of youth physiology and epidemiology. With a theoretical understanding of MDS, practitioners will be more informed on the planning and periodization...

Dos'Santos, T, Thomas, C, Comfort, P, and Jones, PA. Biomechanical effects of a 6-week change-of-direction technique modification intervention on anterior cruciate ligament injury risk. J Strength Cond Res XX(X): 000-000, 2021-The aim of this study was to evaluate the biomechanical effects of a 6-week change-of-direction (COD) technique modificatio...

Abstract: This study aimed to examine the effects of change of direction (COD) speed and technique modification training on 180� turning performance (completion time, ground contact time [GCT], and exit velocity), kinetics, and kinematics. A non-randomised 6 week intervention study was administered. Thirteen male multidirectional sport athletes for...

Objective: In soccer, vertical jump means jumping toward a ball. Since no vertical jump test includes the ball as a reference element, the effect that the ball would have in a vertical jump test is unknown. The aim of this study was to examine the biomechanical differences between run-up vertical jump measurements without (Run-up Vertical Jump) and...

In this study, we aimed to analyze the magnitude and direction of interlimb asymmetries in ankle dorsiflexion range of motion (ROM), power (using iso-inertial devices), and a neuromuscular skill (change of direction). Secondarily, we aimed to determine the relationship between interlimb asymmetry scores for each test and also between these scores a...

Thomas, C, Dos'Santos, T, Warmenhoven, J, and Jones, PA. Between-limb differences during 180° turns in female soccer players: application of statistical parametric mapping. J Strength Cond Res 36(11): 3136-3142, 2022-This study was exploratory in nature and investigated the ability of statistical parametric mapping (SPM) to assess between-limb diff...

Practitioners usually include change of direction (COD) and linear speed measurements in the testing batteries of soccer players; however, despite being a commonly occurring action, curve sprint (CS) ability is rarely assessed in soccer. The aims of this study were to analyze the association between linear sprint, CS, and COD speed performances, an...

The aim of the study was to compare ground reaction force (GRF) characteristics between the antepenultimate foot contact (APFC), penultimate foot contact (PFC), and final foot contact (FFC), and to examine the relationships between APFC, PFC, and FFC GRF characteristics with 505 change of direction (COD) speed performance. Twenty university male so...

The purpose of this study was to identify whether ten repetitions and three trials were necessary to achieve stability in peak reactive strength index (RSI) during the 10/5 repeated jumps test (RJT). Twenty-five males, from multiple sports, performed three trials of the RJT on an in-ground force plate, with 90 seconds' rest between trials. Intracla...

Background Cutting actions are associated with non-contact ACL injuries in multidirectional sports due to the propensity to generate large multiplanar knee joint loads (KJLs) that have the capacity to increase ACL loading and strain. Numerous studies have investigated the biomechanical determinants of KJLs in cutting tasks. The aim of this systemat...

Change of direction manoeuvres is important in soccer and associated with non-contact anterior cruciate ligament injury, yet it is not known how the mechanics differentiate between males and females during 180° turns. Twenty-eight soccer players (14 males and 14 females) performed 180° turns with ground reaction forces collected over penultimate an...

Background In youth, the development of change of direction (COD) and sprint performance is a key component for successfully competing in soccer across age. During a COD, the presence of directional asymmetries may be detrimental due to the unpredictable nature of the sport. Therefore, the aims of the study were to investigate asymmetries in COD ab...

The countermovement jump (CMJ) is considered an important test in rugby league, and the force platform is the recommended tool for assessing CMJ performance in this cohort. Because of inconsistent methods applied across previous studies, there is currently a lack of understanding of what constitutes a “good” CMJ performance, with respect to the typ...

Purpose: The reactive strength index (RSI) provides a value that indicates how efficiently an athlete can utilize the stretch shortening cycle. This study aimed to compare RSI values between the 10/5 repeated jumps test (RJT) and drop jumps (DJs) from 30 cm (DJ30) and 40 (DJ40). Methods: Thirty males (age = 23.97 ± 5.94, height (m) = 1.80 ± 0.08 an...

The countermovement jump (CMJ) test and multiple-repetition rebound jump (RJ) test (usually, 3-5 RJs) are routinely conducted with athletes to evaluate their neuromuscular function (NMF) and stretch-shortening cycle (SSC) ability, respectively. Jump height (JH), reactive strength index (RSI) and RSI modified (RSImod) are regularly reported for thes...

Thomas, C, Dos'Santos, T, Comfort, P, and Jones, PA. Effect of asymmetry on biomechanical characteristics during 180° change of direction. J Strength Cond Res XX(X): 000-000, 2020-The aim of this study was to explore the effect of asymmetry on biomechanical characteristics during two 180° change of direction (CoD) tasks (505 and modified 505 [505mo...

Comfort, P, Jones, PA, Thomas, C, Dos'Santos, T, McMahon, JJ, and Suchomel, TJ. Changes in early and maximal isometric force production in response to moderate- and high-load strength and power training. J Strength Cond Res XX(X): 000-000, 2020-The aims of this study were to determine the changes in early (50-, 100-, 150-, 200-, 250 ms) and maximal...

Change of direction (COD) manoeuvres are associated with anterior cruciate ligament (ACL) injury risk due to the propensity to generate large multiplanar knee joint loads. Given the short- and long-term consequences of ACL injury, practitioners are interested in methods that reduce knee joint loads and subsequent ACL loading. An effective strategy...