Physical activity, sleep pattern and energy expenditure in double-handed offshore sailing

AIM: The aim of the present study was to quantify total energy expenditure, activity energy expenditure and time spent at three levels of physical activity (low, moderate, high intensity) in four two--person crews during a 500--mile double--handed sailing regatta. METHODS: Physical activity intensity and energy expenditure were assessed during a 500 nautical miles double--handed offshore competition in eight male sailors (46.3 ± 3.4 years; 180 ± 13 cm; 85.4 ± 12.5 kg). They wore continuously an activity monitor that estimates energy expenditure and minutes spent at each level of intensity (sedentary, < 1.5; light physical activity, 1.5 - 2.9; moderate physical activity, 3.0 - 6.0; vigorous physical activity, > 6.0 METs). RESULTS: The sailors spent longer periods (P < 0.0001) of time in sedentary (823 ± 193 min⋅d--1) and light physical activities (516 ± 177 min⋅d--1) than in moderate (95 ± 34 min⋅d--1) or vigorous (6 ± 4 min⋅d--1) physical activities. They slept 5 times per day (± 1.4) for 36 min (± 9) in each sleeping period. The total energy expenditure was 14.26 ± 1.89 MJ⋅day--1 and the activity energy expenditure was 5.06 ± 1.42 MJ⋅day--1. Activity energy expenditure was significantly correlated with total sleep time, boat speed, and distance covered each day (P < 0.05). CONCLUSION: The high total energy expenditure was more likely a consequence of the short and rare periods of sleep during the competition rather than of the bouts of moderate and vigorous physical activities.