Craig Twist is Professor of Applied Sport & Exercise Science at Liverpool John Moores University, UK, and has primary research interests in the training and monitoring of rugby players. Craig is an accredited Sport and Exercise Scientist with the British Association of Sport and Exercise Sciences. Paul Worsfold is Head of Biomechanics at the UK Sports Institute and Professor in Sports Biomechanics and Performance Analysis at the University of Chester, UK. His applied and research interests are primarily focused on optimising athlete movement and technology to enhance performance and reduce injury.