The aim of this study was to measure forces acting on a laser sailor in order to obtain an indication of the physical demands in the major muscle groups used during dinghy racing. Force data were collected in the mainsheet and the hiking strap of a club level (body weight 94kg) and an elite sailor (body weight 80kg) in a range of wind conditions. The highest average and peak hiking strap forces were 647 N (59% of MVC) and 843 N (77% of MVC) respectively, recorded for the club level sailor. The highest average and peak mainsheet forces of 111 N (35% of MVC) and 289 N (90% of MVC) respectively were also recorded for the club sailor. The elite and the club sailors' results were similar in most cases. Differences were attributed to differing body weights and technique. The results provide a preliminary indication of the intensity of muscular forces required in a physical training programme for laser racing.