Clinical Biomechanics in Sport

Original Editor - Wanda van Niekerk based on the course by Ian Gatt
Top Contributors - Wanda van Niekerk, Jess Bell and Kim Jackson

Introduction[edit | edit source]

Clinical biomechanics in sports can be used to enhance sports performance and reduce injury. A wide range of techniques are used such as computer simulations, measurements and mathematical modelling in various sports and exercises.

Biomechanics Definitions[edit | edit source]

Biomechanics is the study of the structure and function of biological systems by means of the methods of mechanics.[1] A more relevant definition to sports clinicians is[1]:

“The application of mechanical principles in the study of living organisms”

Sport and exercise biomechanics encompass the area of science concerned with the analysis of the mechanics of human movement.[1] It refers to the description, detailed analysis, and assessment of human movement during sport activities.[2] Mechanics is a branch of physics that is concerned with the description of motion/movement and how forces create motion/movement. In other words, sport biomechanics is the science of explaining how and why the human body moves in the way that it does. In sport and exercise, that definition is often extended to also consider the interaction between the athlete and their equipment and environment.

Biomechanics is traditionally divided into the areas of[1]:

  1. Kinematics - a branch of mechanics that deals with the geometry of the motion of objects, including displacement, velocity, and acceleration, without considering the forces that produce the motion. It is the study of the description of motion.
  2. Kinetics - study of the relationships between the force system acting on a body and the changes it produces in body motion. It is the study of the forces and torques that cause motion of a body.

In terms of these areas, there are skeletal, muscular and neurological considerations when describing biomechanics.[2]


Application of Biomechanics[edit | edit source]

  • Orthopaedic biomechanics[5]
    • Design of artificial limbs, joints and orthoses to improve functional movement
    • Study of natural and artificial biological tissues
  • Occupational biomechanics[6]
    • Ergonomics and human factors
    • Reduction of workplace injury
  • Biomechanics of other biological systems[7]
    • Comparative biomechanics (e.g. locomotion in animals)
    • Equine racing performance
  • Exercise and sport biomechanics
    • Traditionally sports biomechanics is aimed at[8]:
      • Improving performance
      • Treatment and prevention of injury
    • Some of the areas where biomechanics is applied to improve performance or prevent issues in sports are:
      • Identification of optimal technique for improving sports performance
      • Analysis of body loading to find the safest way to perform a particular sport or exercise task
      • Assessment of muscle recruitment and loading
      • Analysis of sport and exercise equipment and implementing design  (e.g. shoes, surfaces, racquets, clubs, bats, helmets, bikes)

Principles of Biomechanics[edit | edit source]

Knowledge of several biomechanical terms and principles is useful when considering the role of biomechanics in sport and exercise. Read more about these principles such as force, torque, Newton's laws of motion, momentum, centre of gravity and balance here: Principles of Biomechanics.

[9]

Correct Biomechanics[edit | edit source]

  • Correct biomechanics provide efficient movement and may reduce injury risk[2]
  • Abnormal or faulty biomechanics in sports may be a possible reason for injury
  • Abnormal biomechanics can be a result of anatomical or functional abnormalities

Different movement planes of motion and axes of motion are often used in biomechanics. Have a look at this video to refresh your memory.

[10]

Incorrect technique can lead to abnormal biomechanics which can lead to injury. Some examples of the relationship between technique and associated injuries are listed in the table below.

Sport Technique Injury
Cricket[11] Mixed bowling action Pars interarticularis stress fractures
Tennis[12] Excessive wrist action with the backhand Extensor tendinopathy of the elbow
Swimming[13] Decreased external rotation of the shoulder Rotator cuff tendinopathy
Running[14] Anterior pelvic tilt Hamstring injuries
Rowing[15] Change from bow side to stroke side Rib stress fractures
Ballet[16] Poor turnout Hip injuries

Read more:

Examples of Sports using Biomechanics[edit | edit source]

Running[edit | edit source]

Cycling[edit | edit source]

  • The aim of biomechanics applied to cycling is to improve the cyclist’s interaction with the bicycle by improving the comfort of the position (posture) and efficiency (pedalling).
  • Read more:

Tennis[edit | edit source]

  • The biomechanics of tennis stroke and serve techniques are complex. Furthermore, the equipment choices such as the racquet and the range of surfaces add to this complexity. Forces from the ball/racquet impact during different and repetitive strokes can lead to upper limb overuse injuries and player-surface interactions often lead to lower limb acute injuries.[19]
  • Read more:

Baseball[edit | edit source]

  • Increased stress is placed on the elbow and shoulder in a player with improper throwing or pitching biomechanics and this leads to an increased risk of injury.
  • Biomechanical assessments of throwing can identify issues in performance and injury and it is important for clinicians to understand these biomechanics.[21]
  • Read more:

Golf[edit | edit source]

  • Clinicians working with golf players need to understand some important factors linked to the golf swing, this will help guide testing as well as rehabilitation and exercise prescription.[22] These factors can include:
    • The x-factor – rotation of the thoracic spine relative to the pelvis at the top of the backswing
    • The x-factor stretch – maximal x-factor that occurs during the start of the downswing, as the pelvis begins to rotate back towards the target
    • Research has shown that if the x-factor stretch (the rotational gap between the pelvis and upper body) can be widened it can increase driving distance
    • The impact of ground reaction forces during the golf swing

Boxing[edit | edit source]

  • Bent arm shot in boxing
    The two main shots in boxing are:
    • Bent arm shot
    • Straight arm shot
  • Dinu et al.[23] examined the biomechanics of the cross, hook and uppercut between two elite boxing groups (seniors vs juniors). The authors reported the following[23]:
    • The elbow contributed the most to the cross which is a straight arm shot
    • The shoulder contributed the most to the hook and uppercut shots which are bent arm shots
    • In junior elite boxers, the shoulder contribution for all three shots (cross, uppercut and hook) was higher than in senior boxers indicating that there is more motion at the shoulder in inexperienced boxers compared to experienced boxers.
  • Biomechanical assessments such as these provide valuable information for clinicians and athletes to improve performance and refine training and rehabilitation practices. Furthermore, it provides a better understanding of why certain types of injuries occur.

A Clinician’s Perspective and Journey with the Clinical Use of Biomechanics in Boxing[edit | edit source]

Forces working on the carpometacarpal joint

Another example of the usefulness of biomechanics to clinicians is with hand and wrist injuries in boxing. Hand-wrist injuries account for 6 – 35% of all boxing injuries in training and competition. The most common injury is carpometacarpal instability of the hand. This injury also incurs the most time loss from training.[24][25] 

Injury mechanism of the carpometacarpal joint

In the images on the right the injury mechanism of the carpometacarpal joint in a boxer’s hand is explained. The yellow line represents the metacarpal bone, the blue line represents the carpal bones. The dark blue arc represents the dorsal ligaments. The red arrows represent the forces applied and the golden arrows represent residual forces. If the boxer takes a shot with the metacarpal bone in a poor or bad position, forces will cause injury such as instability.



Sports Physiotherapist's Quest to Understand Hand Wrapping Techniques in Boxing and the Link to Injury[edit | edit source]
Methodology of measuring wrist kinematics

There is an uniqueness to investigating wrist kinematics in boxing. This is because it is not viable to use the various camera technologies typically used in biomechanics because the hand is wrapped in bandages and a boxing glove. Using a camera approach will not provide accurate measurements of specific movements taking place.

A key consideration in biomechanical assessments is the equipment. What is available and will it work for the intended purpose? Is the equipment valid and reliable? A novel method of determining wrist joint angles in boxing using an electromagnetic tracking system was used by Gatt et al.[26] and found to be a reliable and valid method.

Read the complete article here: Accuracy and repeatability of wrist joint angles in boxing using an electromagnetic tracking system.[26]

This reliable and valid method was then applied to investigating wrist kinematics on impact for the hook and jab lead arm shots in boxing. It was found that when elite boxers hit a punching bag, ulnoflexion occurred in both the jab (> 30% of total wrist motion) and hook (> 20% of total wrist motion) shots.[27] With this finding, it is evident that on impact, there is not only wrist flexion, but also ulnar deviation. This is known as a dart-throwing motion (DTM) which is a normative biaxial motion. This provides insight into why certain wrist injuries happen on the ulnar side through compression, and on the radial side through a traction-type mechanism.[27]

Read the complete article here: Quantifying wrist angular excursion on impact for Jab and Hook lead arm shots in boxing.[27]

Biomechanics in sports provides clinicians, coaches and researchers with significance and insight. For example, quantifying wrist angular excursion on impact can provide insight into different types of bandaging techniques that can be applied in boxing to prevent injuries or reduce the risk thereof.

Methods of Measurement in Biomechanics[edit | edit source]

Biomechanical testing can be done in the lab or in the field, during training or competition. The type of sport and skills of the sport will determine the testing procedures necessary. The coach, clinician and/or athlete need to be involved in the problem-solving process to give valuable and relevant information on the issue that needs to be addressed.

  • Motion capture[28]
    • Three-dimensional motion analysis
    • Appropriate for many sports involving complex movement
    • Captures complex processes of human motion not observable by the human eye and quantifies the attributes of motion
  • Accelerometers, gyroscopes and lasers[29][30]
    • Used to determine the technical characteristics of an athlete's motion
  • Force platforms[31]
    • Force plate analysis
    • Used for walking, running and landing activities
    • Useful to determine impact, braking and propulsive forces
    • Useful to determine weight transfer in dynamic activities
    • Useful in the calculation of joint kinetics
  • Electromyography[32]
    • Used for measuring muscle activity
  • High speed video analysis[33]
    • Using high speed cameras to analyse high speed movements and impact
  • Competition analysis[34]
    • Performance variables of an athlete are measured such as split times, stride length or stride rate, stroke length or stroke rate

Final Thoughts[edit | edit source]

  • Biomechanics – consider kinetics and kinematics
  • Using biomechanics to influence and assess injuries and performance
  • Sport significance – this must be relevant to the sport and viable to investigate or assess
  • Opportunity for live and retrospective analysis depending on technology and human resources

Resources[edit | edit source]

References[edit | edit source]

  1. 1.0 1.1 1.2 1.3 Hall SJ. Basic Biomechanics, 8e. McGraw-Hill; 2019.
  2. 2.0 2.1 2.2 Brukner P. Clinical sports medicine: Injuries. McGraw-Hill Education (Australia) Pty Limited; 2017.
  3. CREATe at Vanderbilt University. Biomechanics: When Sports Meets Science. Available from: https://www.youtube.com/watch?v=vglcn72rfEM&t=76s [last accessed 11/5/2022]
  4. STEM Learning. Understanding the biomechanics of sport. Available from: https://www.youtube.com/watch?v=Aqo0w0PwZgk [last accessed 11/5/2022]
  5. Putame G, Aldieri A, Audenino A, Terzini M. Orthopedic biomechanics: multibody analysis. InHuman Orthopaedic Biomechanics 2022 Jan 1 (pp. 39-69). Academic Press.
  6. Lim S, D'Souza C. A narrative review on contemporary and emerging uses of inertial sensing in occupational ergonomics. International journal of industrial ergonomics. 2020 Mar 1;76:102937.
  7. Mouloodi S, Rahmanpanah H, Gohari S, Burvill C, Tse KM, Davies HM. What can artificial intelligence and machine learning tell us? A review of applications to equine biomechanical research. Journal of the Mechanical Behavior of Biomedical Materials. 2021 Nov 1;123:104728.
  8. Knudson D. Applying Biomechanics in Exercise and Rehabilitation. InFundamentals of Biomechanics 2021 (pp. 177-186). Springer, Cham.
  9. Flip Teach.Basic biomechanics part 1. Available from: https://www.youtube.com/watch?v=XMzh37kwnV4&t=10s[last accessed 11/5/2022]
  10. ParklandCSIT. Axis Of Movement animation 2012. Available from: https://www.youtube.com/watch?v=iP7fpHuVaiA&t=8s[last accessed 11/5/2022]
  11. Forrest MR, Hebert JJ, Scott BR, Brini S, Dempsey AR. Risk factors for non-contact injury in adolescent cricket pace bowlers: a systematic review. Sports medicine. 2017 Dec;47(12):2603-19.
  12. Stuelcken M, Mellifont D, Gorman A, Sayers M. Wrist injuries in tennis players: a narrative review. Sports medicine. 2017 May;47(5):857-68.
  13. Johnston T.R., Abrams G.D. Shoulder Injuries and Conditions in Swimmers. In: Miller T. (eds) Endurance Sports Medicine. Springer, Cham. 2016:127-138.
  14. Goom TS, Malliaras P, Reiman MP, Purdam CR. Proximal Hamstring Tendinopathy: Clinical Aspects of Assessment and Management. J Orthop Sports Phys Ther. 2016 Jun;46(6):483-93
  15. D'Ailly PN, Sluiter JK, Kuijer PP. Rib stress fractures among rowers: a systematic review on return to sports, risk factors and prevention. The Journal of Sports Medicine and Physical Fitness. 2015;56(6):744-753.
  16. Bowerman EA, Whatman C, Harris N, Bradshaw E.  Review of the Risk Factors for Lower Extremity Overuse Injuries in Young Elite Female Ballet Dancers. Journal of Dance Medicine & Science. 2015; 19:51-56
  17. Folland JP, Allen SJ, Black MI, Handsaker JC, Forrester SE. Running technique is an important component of running economy and performance. Medicine and science in sports and exercise. 2017 Jul;49(7):1412.
  18. Souza RB. An evidence-based videotaped running biomechanics analysis. Physical Medicine and Rehabilitation Clinics. 2016 Feb 1;27(1):217-36.
  19. Allen T, Dixon S, Dunn M, Knudson D. Tennis equipment and technique interactions on risk of overuse injuries. InTennis medicine 2018 (pp. 61-79). Springer, Cham.
  20. Martin C. Tennis serve biomechanics in relation to ball velocity and upper limb joint injuries. Journal of Medicine and Science in Tennis. 2014;19(2).
  21. Diffendaffer AZ, Bagwell MS, Fleisig GS, Yanagita Y, Stewart M, Cain Jr EL, Dugas JR, Wilk KE. The Clinician’s Guide to Baseball Pitching Biomechanics. Sports Health. 2022 Apr 23:19417381221078537.
  22. Bishop C, Ehlert A, Wells J, Brearley S, Brennan A, Coughlan D, Belfry UK. Strength and conditioning for golf athletes: biomechanics, injury risk, physical requirements, and recommendations for testing and training. Professional Strength & Conditioning. 2022 Feb 18.
  23. 23.0 23.1 Dinu D, Millot B, Slawinski J, Louis J. An examination of the biomechanics of the cross, Hook and uppercut between two elite boxing groups. Multidisciplinary Digital Publishing Institute Proceedings. 2020;49(1):61.
  24. Loosemore M, Lightfoot J, Gatt I, Hayton M, Beardsley C. Hand and wrist injuries in elite boxing: a longitudinal prospective study (2005-2012) of the Great Britain Olympic Boxing Squad. Hand. 2017 Mar;12(2):181-7.
  25. Loosemore M, Lightfoot J, Palmer-Green D, Gatt I, Bilzon J, Beardsley C. Boxing injury epidemiology in the Great Britain team: a 5-year surveillance study of medically diagnosed injury incidence and outcome. British journal of sports medicine. 2015 Sep 1;49(17):1100-7.
  26. 26.0 26.1 Gatt IT, Allen T, Wheat J. Accuracy and repeatability of wrist joint angles in boxing using an electromagnetic tracking system. Sports Engineering. 2020 Dec;23(1):1-0.
  27. 27.0 27.1 27.2 Gatt I, Allen T, Wheat J. Quantifying wrist angular excursion on impact for Jab and Hook lead arm shots in boxing. Sports Biomechanics. 2021 Dec 8:1-3.
  28. van der Kruk E, Reijne MM. Accuracy of human motion capture systems for sport applications; state-of-the-art review. European journal of sports science. 2018 Jul 3;18(6):806-19.
  29. Fridolfsson J, Börjesson M, Arvidsson D. A biomechanical re-examination of physical activity measurement with accelerometers. Sensors. 2018 Oct;18(10):3399.
  30. Tierney G. Concussion biomechanics, head acceleration exposure and brain injury criteria in sport: A review. Sports biomechanics. 2022 Jan 1:1-29.
  31. Parry GN, Herrington LC, Horsley IG, Gatt I. The test–retest reliability of bilateral and unilateral force plate–derived parameters of the countermovement push-up in elite boxers. Journal of Sport Rehabilitation. 2021 Feb 24;1(aop):1-5.
  32. Taborri J, Keogh J, Kos A, Santuz A, Umek A, Urbanczyk C, van der Kruk E, Rossi S. Sport biomechanics applications using inertial, force, and EMG sensors: A literature overview. Applied bionics and biomechanics. 2020 Jun 23;2020.
  33. Della Villa F, Tosarelli F, Ferrari R, Grassi A, Ciampone L, Nanni G, Zaffagnini S, Buckthorpe M. Systematic video analysis of anterior cruciate ligament injuries in professional male rugby players: pattern, injury mechanism, and biomechanics in 57 consecutive cases. Orthopaedic journal of sports medicine. 2021 Nov 2;9(11):23259671211048182.
  34. Barbosa TM, Barbosa AC, Simbaña Escobar D, Mullen GJ, Cossor JM, Hodierne R, Arellano R, Mason BR. The role of the biomechanics analyst in swimming training and competition analysis. Sports Biomechanics. 2021 Aug 26:1-8.
  35. McErlain-Naylor S. Sports Biomechanics Lecture Series. Available from https://www.youtube.com/watch?v=3qyoVGkPQF4&list=PLI7VLEjUJidBpOCEyXIfHVHfLa5AhSqUm (last accessed 11/5/2022)