Richard C. Armitage is the general practitioner in the Academic Unit of Population and Lifespan Sciences, School of Medicine at the University of Nottingham, Clinical Sciences Building, Nottingham City Hospital Campus, Hucknall Road, Nottingham, NG5 1PB, England ([email protected]). Please address all correspondence to Richard C. Armitage.

Eric Williamson is the physiotherapy student in the Department of Sport Exercise and Rehabilitation, Coach Lane Campus at the Northumbria University.