Energy Expenditure was measured with doubly labelled water technique during heavy
sustained exercise with an official finishing team in the Race Across America. Energy
Intake was also calculated to produce an energy balance for the race. A team of 4
cyclists (Mean ±SD age: 37+4 yr; body height: 182+8 cm; body mass: 80.8+6.6 kg) completed
the race in a relay fashion. The team completed the race in 6 days 10 h and 51 min.
Total mean energy expenditure was found to be 43 401 kcals (181 711 kJ) with a mean
daily energy expenditure of 6 420 kcals (26 879 kJ). Total mean energy intake from
all food and drink consumed was calculated at 29 506 kcals (123 536 kJ) with a mean
daily energy intake of 4 918 kcals (20 591 kJ). This resulted in a total mean energy
deficit of 13 878 kcals (58 104 kJ) with a mean daily energy deficit of 1 503 kcals
(6 293 kJ). The high energy expenditure highlights the need for correct and practical
dietary strategies and challenges nutritionists to devise high energy diets that not
only contain the correct macronutrient balance, but are also palatable to the cyclists,
thus encouraging a high energy intake.
doubly labelled water - energy expenditure - ultra endurance exercise
