1 Department of Musculoskeletal Disorders, Faculty of Medicine and Surgery, University of Salerno, Salerno, Italy.
2 Queen Mary University of London, Barts and the London School of Medicine and Dentistry, Centre for Sports and Exercise Medicine, Mile End Hospital, London E1 4DG, England.
3 Institute of Science and Technology in Medicine, Keele University School of Medicine, Stoke on Trent, England.