Analysis of sailing variables and performance of laser sailors with different rankings under the condition of certain wind speed.

Objective: The aims of this study were to describe the characteristics of sailing variables and differences between different ranking sailors under the condition of certain wind speed, and predict the variables that affect performance. Methods: Five regatta's data of the 2019-2020 Hempel World Cup Series and Tokyo 2020 Olympic Games for a total of 63 races were analyzed in this study. The wind speed was defined as light wind below 8 knots, medium wind at 8-12 knots and strong wind above 12 knots. Sailors were divided into top 10 and other ranked groups based on their performance for each race. Results: 1) The race time of Laser class was about 50 min. The sailing distance traveled, VMG, percentage of upwind time, and the number of downwind maneuvers increased with an increase in the wind speed, while upwind maneuvers decreased increasing wind speed. Under the same wind speed, the VMG of reaching legs was the highest, followed by downwind and upwind legs in same wind speed. (2) The top 10 sailors had a high VMG, less race time, upwind/reaching legs' time and distance compared to other ranked sailors in all categories of wind speed ( Conclusions: Wind speeds affect sailing variables and race characteristics. VMG and time and distance in upwind and reaching legs are important variables for differentiating sailors' level. Regardless of the wind speed, the first upwind mark position of sailors can be used as an effective factor in predicting the performance of the race.