Biomechanics

Overview

The biomechanics team within the PHC seek to gain an understanding of the mechanics of sports movements. At this present time we have a biomechanical interests in wheelchair sports, handcycling and amputee running/long-jump. Such questions we are currently challenging are; how to best configure the daily and sports wheelchair/handbike; how the approach speed, leg plant angle and knee angle affect long jumping performance; and what technique influences ball speed during the tennis serves. Further research is utilising machine learning approaches to understand gait and muscle activation patterns in lower limb amputees during walking activities, to attempt to improve existing rehabilitation techniques.

Motor control goes beyond the mechanics of movement and seeks to gain an understanding of sports technique from a perspective of coordination and neuro-muscular control. Some of our more recent research aims to answer how scapular variability may be associated with shoulder pain in wheelchair athletes. You can find out more about this research under our strand.

Overview

Recumbent handcycling is an endurance sport for individuals with lower and upper limb impairments. Performance levels have continually increased over recent years, which has largely been due to developments in technology with lighter, customized handbikes frequently used by competitive handcyclists. That said, there are several components to a handbike that can be configured in a variety of different ways. The impact of handbike configuration on performance has been severely under researched, and subsequently further gains in performance could be possible, which was the objective of the current project.

Findings

The project first sought to understand which areas of handbike configuration were in greatest need of research and to determine what highly trained handcyclists did biomechanically compared to recreational handcyclists. This preliminary research identified that the horizontal positioning of the crank and the length of the cranks were of were of greatest interest to athletes and coaches and that highly trained handcyclists configured their handbikes in a way that created more trunk flexion and elbow extension than recreational handcyclists.

Subsequent research established that selecting a horizontal crank position between 97-100% of an individual’s arm length maximized their physiological economy. It was later revealed that the optimal crank length was dependent on handcyclists self-selected cadences. Those with a higher cadence were more economical in shorter 150mm cranks, whereas those with a slightly lower cadence benefitted from slightly longer, 160mm cranks.

This work was funded by the English Institute of Sport (EIS) and has been used to support the recumbent handcyclists from British Cycling throughout the Tokyo Paralympic cycle.

Overview

Wheelchair tennis (WT) is played by individuals with lower-limb impairments (Open division) and both upper- and lower-limb impairments (Quad division) and strongly resembles the able-bodied (AB) version of the sport, with the exception of the 2-bounce rule in WT.

As with AB tennis, the serve is of the upmost importance, as points typically don’t last long in WT. However, unlike AB tennis, little empirical research has explored the kinematics of the tennis serve in WT. Subsequently, the purpose of this project is to understand more about the important biomechanical characteristics that contribute towards successful tennis serves in WT and how different impairments can influence the execution of this complex, yet vital skill. 

Findings

Extensive work has been undertaken to collect high-quality biomechanical data from some highly trained WT players performing a variety of tennis serves. Subsequently, analysis has been limited and has been restricted to a comparison between 2 males from the Open and Quad division respectively.

Qualitatively, these analyses have revealed that a relationship does exist between impairment and serve performance. Quad’s demonstrated a limited range of movement in trunk rotation, internal and external rotation of the shoulder and elbow extension compared to the players from the Open division. Consequently, reduced racket head speeds were generated and in conjunction with greater variability in racket head location at ball contact resulted in lower service speeds for Quad’s compared to those from the Open division.

Work is ongoing to better understand the contribution on upper body kinematics and its contribution to both ball spin and speed during the tennis serve to ultimately help players and coaches optimize this aspect of their performance.