Paul A Jones

University of Salford · Centre for Health Sciences Research

Change of direction deficit (CODD) offers valuable insights into a player’s balance between linear and multidirectional speed. However, there are still no established reference values for CODD. The objectives of this study were to determine CODD thresholds for various change of direction angles in basketball players according to gender and analyse...

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...

The objective of this scoping review is to identify and map the approaches of current literature in biomechanically quantifying the gross-motor movement of children.

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...

This study aimed to assess movements occurring during goal scoring situations in a female professional league.Data from all the goals on the Women's Super League 2018/2019 were collected through time-motion analysis using a modified version of the Bloomfield Movement Classification with differences analysed through chi-square. Analysis was performe...

This study compared the efficacy of linear, non-linear and differential methods on variables related to ACL injury risk of a side-step cutting task in male and female basketball players. Thirty males and thirty females practiced basketball skills in sixty 90-minute sessions across 5 months. Ten players trained in each of the LP, NLP and DL female/m...

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...

Background: Several biomechanical outcomes are being used to monitor the risk of injuries; therefore, their reliability and measurement errors need to be known. Objective: To measure the reliability and measurement error in lower limb 3D gait analysis outcomes during a 90∘ and 135∘ change of direction (COD) manoeuvre. Methods: A test re-test r...

The purpose of this study was to examine the relationship between frontal plane knee projection angle (FPPA) and sagittal (hip and knee flexion) plane landing kinematic measures during a drop jump (DVJ) and a tuck jump assessment (TJA) test in male youth football players. Eighty-one post-pubertal male footballers were recorded performing DVJ and TJ...

Flywheel resistance training devices (FRTD) is shown effective in improving strength, sprinting, jumping and changes of direction (COD) performance in male soccer players, however, this is not elucidated in female soccer players. We aimed to assess the effect of FRTD on these physical abilities in females soccer players. 24 professional female socc...

The aim of this study was to quantify changes in typical (i.e., jump height) and alternative (i.e., jump momentum) countermovement jump (CMJ) outcome and strategy variables, alongside maximal strength, during the early English Super League pre-season period. Twenty professional senior male rugby league players from an English Super League club perf...

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...

Research into the physical demands of Gaelic football is limited with no research into the agility or change of direction (CoD) demands of the sport. This study examined the CoD demands of Gaelic football via a time-motion analysis of senior inter-county match play. The Bloomfield movement classification (BMC) was adapted for application to Gaelic...

Data were collected through time-motion analysis from soccer players participating in the English Premier League using a modified version of the Bloomfield Movement Classification with differences analysed through chi-square. The most common individual movement preceding a goal was a linear advancing motion (32.4 ± 1%), followed by deceleration (20...

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...

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...

Background If interplanetary travel is to be successful over the coming decades, it is essential that countermeasures to minimize deterioration of the musculoskeletal system are as effective as possible, given the increased duration of spaceflight associated with such missions. The aim of this review, therefore, is to determine the magnitude of dec...

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...

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...

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...

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...

The prevention of non-contact anterior cruciate ligament (ACL) injuries often involves movement training, but the effectiveness of different motor learning methods has not been fully investigated. The purpose of this study was therefore to examine the effects of linear pedagogy (LP), nonlinear pedagogy (NLP) and differential learning (DL) motor lea...

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...

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...

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 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...

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...

The purpose of this study was to provide an isokinetic strength profile of female soccer players and examine whether limb preference influences bilateral and reciprocal knee joint muscle balance. Gravity corrected isokinetic (60°·s-1) concentric and eccentric moment-angle profiles of both limbs were collected from 25 female soccer players from the...

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...

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...

The purpose of the current study was to ascertain the between-trial reliability of peak force (PF) and mean force (MF) during the Nordic hamstring exercise (NHE) performed on the Nordbord and determine bilateral differences in PF, MF and instantaneous force (IF). Nineteen strength-trained males performed three NHEs on the Nordbord. PF showed a triv...

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...

Webster, TM, Comfort, P, and Jones, PA. Relationship between physical fitness and the physical demands of 50-over cricket in fast bowlers. J Strength Cond Res XX(X): 000-000, 2020-Professional cricket is constantly evolving and resulting in increased physiological demand placed on players. Fast bowlers experience the greatest physical demand during...

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...

Dos'Santos, T, McBurnie, A, Thomas, C, Comfort, P, and Jones, PA. Biomechanical determinants of the modified and traditional 505 change of direction speed test. J Strength Cond Res XX(X): 000-000, 2019-The aim of this study was to investigate the whole-body biomechanical determinants of 180° change of direction (COD) performance. Sixty-one male ath...

McMahon, JJ, Jones, PA, and Comfort, P. Comparison of countermovement jump-derived reactive strength index modified and underpinning force-time variables between super league and championship rugby league players. J Strength Cond Res XX(X): 000-000, 2019-The countermovement jump (CMJ) is regularly tested in rugby league (RL), with recent work repor...

Jones, PA, Dos'Santos, T, McMahon, JJ, and Graham-Smith, P. Contribution of eccentric strength to cutting performance in female soccer players. J Strength Cond Res XX(X): 000-000, 2019-The aim of this study was to examine the contribution of eccentric strength to performance of a 70-90° cutting task (CUT) (time to complete: 5 m approach, 70-90° cut...

Purpose: To determine the reliability of early force production (50, 100, 150, 200, and 250 ms) relative to peak force (PF) during an isometric mid-thigh pull and to assess the relationships between these variables. Methods: Male collegiate athletes (N = 29; age 21.1 [2.9] y, height 1.71 [0.07] m, body mass 71.3 [13.6] kg) performed isometric mi...

The purpose of this study was to explore whether limb preference influences braking strategy and knee joint mechanics during a 180° pivot task in female soccer players (mean ± SD; age = 20.6 ± 0.6 years; height = 165 ± 7.0 cm; body mass = 56.6 ± 6.3 kg). Three-dimensional motion analyses of pivoting on the preferred and non-preferred kicking limbs...

Cutting manoeuvres are important actions associated with soccer performance and a key action associated with non-contact anterior cruciate ligament injury; thus, training interventions that can improve cutting performance and movement quality are of great interest. The aim of this study, therefore, was to determine the effects of a six-week change...

An important component of change of direction speed is the ability to decelerate. Objective methods to examine this quality have been rarely reported in the literature. The aim of this study was to investigate the within- and between-session reliability (intraclass correlation coefficients (ICC), coefficient of variation (CV), standard error of mea...

This review aims to provide an overview of the current load-velocity (L-V) approaches and their ability to estimate one-repetition maximum (1RM). The bench press exercise appears to be the most valid and reliable when applying this approach. The ability for L-V relationship to predict 1RM for lower-body lifts remains questionable. Individualized re...

McBurnie, AJ, Dos'Santos, T, Jones, PA. Biomechanical associates of performance and knee joint loads during a 70-90° cutting maneuver in subelite soccer players. J Strength Cond Res XX(X): 000-000, 2019-The aim of this study was to explore the "performance-injury risk" conflict during cutting, by examining whole-body joint kinematics and kinetics t...

Performance variables in different counter-movement jump strategies between volleyball players with contrasting take-off velocities

Objective: To assess the validity of the cutting movement assessment score (CMAS) to estimate the magnitude of peak knee abduction moments (KAM) against three-dimensional (3D) motion analysis, while comparing whole-body kinetics and kinematics between subjects of low (bottom 33%) and high CMASs (top 33%). Design: Cross-sectional study. Setting:...

Objective: To critically evaluate the effect of limb dominance on change of direction (COD) biomechanics associated with increased ACL injury-risk. Methods: A systematic review of the literature was conducted using Medline and Sport DISCUS databases. Studies that compared COD biomechanics (lower-limb/whole-body kinetics/kinematics) between limbs...

Introduction Change of direction (COD) manoeuvres are important for many field sports, however they are unfortunately associated with non-contact ACL injuries. Although players frequently COD at >90° angles, limited knowledge is available on knee joint kinematics and kinetics during COD at 90° and 135° and whether limb preference impacts knee mecha...

Abstract Cutting actions are important maneuvers in multidirectional sport and are also key actions associated with non-contact anterior cruciate ligament injury; however, it is important to note that three primary cutting techniques have been studied within the literature: the side-step, crossover cut, and split-step. These cutting techniques demo...

Purpose: Skeletal-muscle function can be evaluated using force-times curves generated via the isometric midthigh pull (IMTP). Various sampling frequencies (500-1000 Hz) have been used for IMTP assessments; however, no research has investigated the influence of sampling frequency on IMTP kinetics. Therefore, the purpose of this study was to investi...

The primary aim of this investigation was to determine the effects of a four-week period of in-season strength training on the dynamic strength index (DSI). Pre and post a four-week period of strength-based training, twenty-four collegiate athletes (age = 19.9 ± 1.3 years; height = 1.70 ± 0.11 m; weight 68.1 ± 11.8 kg) performed three isometric mid...

The purpose of this study was twofold: (1) to examine differences in change of direction (COD) performance and asymmetries between team-sports while considering the effects of sex and sport; (2) to evaluate the relationship between linear speed, COD completion time, and COD deficit. A total of 115 (56 males, 59 females) athletes active in cricket,...

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...

Previous studies have reported an association between global measures of bilateral strength and change of direction (COD) ability. Yet, little is known about the association between unilateral muscle strength qualities and COD ability. The aim of this study was to explore the associations between unilateral muscle strength qualities and COD measure...

The aims of this study were twofold: firstly, to compare lower limb kinematic and kinetic variables during a sprint and 90° cutting task between two averaging methods of obtaining discrete data (peak of average profile vs. average of individual trial peaks); secondly, to determine the effect of averaging methods on participant ranking of each varia...

MOST CHANGE OF DIRECTION BIOMECHANICAL INVESTIGATIONS AND CURRENT TECHNIQUE GUIDELINES FOCUS ON THE ROLE OF THE FINAL FOOT CONTACT. HOWEVER, IT IS EVIDENT THAT PENULTIMATE FOOT CONTACT BRAKING CHARACTERISTICS PLAY AN INTEGRAL ROLE IN DECELERATION BEFORE DIRECTIONAL CHANGES ≥60°; AND CAN THEREFORE, BE DESCRIBED AS A “PREPARATORY STEP.” IN THIS REVIE...

The purpose of this study was to investigate the effect of low-pass filtering on isometric mid-thigh pull (IMTP) kinetics, including body weight (BW), onset threshold force, time-specific force values (50, 100, 150 and 200 ms) and peak force (PF). Forty IMTP trials from twenty-four collegiate athletes (age: 21.2 ± 1.8 years, height: 1.72 ± 0.09 m,...

The aims of this study were to quantify asymmetries in change of direction (COD) performance via completion time and COD deficit, and determine its influence on asymmetry profiling of COD ability. A secondary aim was to evaluate the relationship between linear speed, 505 time and COD deficit. Forty-three youth netball athletes (age: 15.4 ± 1.1 year...

Given the limited accessibility of 3D motion analysis for injury screening of athletes, there is a need to develop a field-based screening tool to identify athletes with ‘at-risk’ cutting mechanics. The aim of this preliminary study was to assess the validity of a qualitative assessment tool for cutting (CMAS) to estimate the magnitude of peak knee...

The purpose of this study was to determine the impact of between limb asymmetries in IMTP force-time characteristics on change of direction speed (CODS). Twenty multisport collegiate athletes (mean ± SD: age: 21.0 ± 1.9 years; mass: 78.7 ± 8.9 kg; height: 1.77 ± 0.04 m) performed three unilateral stance IMTP trials per limb and three modified 505 C...

Cuthbert, M, Thomas, C, Dos'Santos, T, and Jones, PA. Application of change of direction deficit to evaluate cutting ability. J Strength Cond Res 33(8): 2138-2144, 2019-The purpose of this study was to examine the application of the change of direction deficit (CODD) to a 90° cut test to examine whether CODD provides a unique evaluation of an indiv...

Peak force and impulse recorded from a unilateral stance isometric mid-thigh pull are reliable methods of assessing unilateral isometric force production capabilities (ICC ≥0.85; CV ≤9%). In contrast, RFD demonstrated lower reliability (ICC = ≤0.79; CV = ≥19%). ABSTRACT The aim of this study was to determine the between-session reliability of the u...

The dynamic strength index (DSI), often calculated as the ratio of countermovement jump (CMJ) propulsion peak force to isometric mid-thigh pull (IMTP) peak force, is said to inform whether ballistic or maximal strength training is warranted for a given athlete. CMJ propulsion peak force is highly influenced by jump strategy, however, which is not h...

The purpose of this study was to examine the differences in countermovement jump peak force (CMJ-PF), isometric mid-thigh pull peak force (IMTP-PF), and resultant dynamic strength index (DSI) values between team-sport athletes. One hundred and fifteen male and female team-sport athletes performed the CMJ and IMTP to determine peak force (CMJ-PF and...

The purpose of this study was to explore the relationships between isometric mid-thigh pull (IMTP) force-time characteristics (peak force and time-specific force vales (100–250 ms)) and dynamic performance and compare dynamic performance between stronger and weaker athletes. Forty-three athletes from different sports (rowing, soccer, bicycle motocr...

The aims of this study were: 1) to compare the strongest (D) and weakest (ND) limbs in determining muscle strength asymmetry (MSA) ratios among various muscle strength qualities and 2) to determine the relationships among various muscle strength qualities. 17 youth male basketball athletes (age=17.5±0.8 years; height=187.1±9.4 cm; body mass=81.4±10...

The countermovement jump (CMJ) and isometric mid-thigh pull (IMTP) are commonly used to compare one’s force capacity during dynamic and isometric assessments, respectively. However, little research has investigated the influence of maximum isometric strength on drop-jump (DJ) performance. Therefore, the purpose of this study was to explore differen...

Purpose: To investigate (a) the relationships between maximal isometric strength, vertical jump (VJ), sprint speed, and change of direction speed (CODS) in academy netball players, and (b) determine whether players who have high performance in isometric strength testing would demonstrate superior performance in VJ, sprint speed, and CODS measures....

Objectives: To determine the impact of between limb asymmetries in hop performance on change of direction speed (CODS). Design and Methods: Twenty-two multisport collegiate athletes (mean ± SD; age: 21.8 ± 3.4 years, height: 178.1 ± 6.7 cm, mass: 73.5 ± 7.1kg) performed three single and triple horizontal hops for distance per limb, followed by thre...

Purpose: To determine the reliability and variability of dynamic strength index (DSI) calculated from squat jump (SJ) (DSI-SJ) versus countermovement jump (CMJ) (DSI-CMJ) peak force (PF) and to compare DSI values between methods. Methods: Male youth soccer and rugby league players (n = 27; age = 17.2 ± 0.7 years; height = 173.9 ± 5.7 cm; body ma...

The aims of this study were to compare isometric mid-thigh pull (IMTP) peak force (PF), time-specific force values (100-, 150- and 200 ms), rate of force development (RFD) at pre-determined time bands (0-100, 0-150 and 0-200 ms) and net forces between two commonly adopted hip joint angles (145˚[hip145] and 175˚[hip175]) with a 145˚ standardised kne...

Previous studies have reported an association between eccentric strength (ECC-STR) and change of direction (COD) ability. Little is known about how ECC-STR facilitates COD maneuvers. The aim of this study was to examine the role of ECC-STR during a 180° COD task in 18 female soccer players. Each player performed six trials of a 180° COD task whereb...