Energy expenditure during a single-handed transatlantic yacht race

Abstract

This mean TDEE was approximately 25% lower than that reported in a previous study (14.5 vs. 19.3 MJ/day) for a 13-day leg of a fully crewed offshore race. The difference in results was probably due to the fact that in the previous study, the crew operated in "watches" (work shifts), affording each crew member greater opportunity to eat, rest and sleep. Effective planning and efficient management of resources is essential to the success of the solo sailor. However, the extent to which maintenance of energy balance underpins competitive success remains to be established. To maintain energy balance during the race, a mean daily energy intake of 14.5 MJ/day was necessary for the subject in this study. However, this mean value for energy intake would have been inadequate to match the peak energy expended during the most physically demanding 24 hours of the race.

Field study of anthropomorphic and muscle performance changes among elite skippers following a transoceanic race

“…We therefore advocate introducing CFFF measurement into skipper's individual assessment to better identify the optimal moment or need for sleep. As already demonstrated in several studies [4,5,7,33], we observed a significant reduction of bodyweight (-3.6 ± ± 1.4%) at the expense of FM (-36.4 ± 31.4%). According to segmental BIA of FM, the reduction of fat mass was more pronounced in the abdomen (-48.3 ± 28.1%) than in the limbs (-25.1 ± 22.5%).…”

“…The hypothesis of negative energy balance makes sense in regards of the significant reduction of waist circumference. Indeed, according to different studies the mean total daily energy expenditure during offshore race may vary between 14.5 [33] and 19.3 MJ/d [4], which is very high. More, it was demonstrated on an offshore race of 500 nautical miles long that the time spent performing sedentary (< 1.5 METs, excluding sleeping) or light activity (between 1.5 and 2.9 METs) predominates with an average of 92% of the wake time [11].…”

Maximal Sustained Levels of Energy Expenditure in Humans during Exercise

“…This shows that military rations alone and in restricted availability will cause eventual problems even when TEE and PAL are conservative. Finally, a study in one racer competing in a transatlantic yacht race had a PAL of 2.7 but weight loss of 1.8 kg wk"' (18). To summarize, it is quite likely that El was limited in each of these three studies and that limitation, rather than extremely high EEs or PALs, led to more extreme eatabolic losses in the body.…”

“…When calculated this way, some of the largest decreases in body weight were found in studies of shorter duration. Forbes-Ewan et al (7) reported a 2.3-kgwk"' weight loss (study period was 7 d), and Myers et al (18) found a 1.8-kg wk"' weight loss (study duration was 13 d). Interestingly, the PALs in those studies, 2.7 for both, were some of the lowest reported in our analysis.…”

“…Therefore, it may be the lack of energy intake (El) rather than PAL achieved that would be affecting weight loss. We decided to explore this a little more and split the studies up into those that seemed to have some energy restriction (3,7,11,(13)(14)(15)17,18,20,25,29) versus those that did not have energy restriction (1,(3)(4)(5)(6)8,12,16,22,23,26). There was no correlation between weight change per week and PAL for energy-restricted studies (r = -0.03, NS); however, there was a fairly strong positive correlation, albeit not statistically significant, between weight change per week and PAL for the non-energy-restricted studies {r = 0.52, P = 0.15).…”