DAILY ENERGY-EXPENDITURE IN MALE ENDURANCE ATHLETES WITH DIFFERING ENERGY INTAKES

The 24-h energy expenditure (24-h EE), resting EE (REE), sleeping EE ( SEE), and spontaneous physical activity (SPA) were compared between si x male endurance athletes whose reported energy intake was low (LOW) a nd did not match that theoretically required for weight maintenance an d four whose reported energy intake appeared adequate (ADQ) and matche d their estimated EE. Groups did not differ in age, body weight, fat-f ree mass, and daily EE estimated from activity records. The LOW athlet es reported an energy intake 6338 +/- 2164 kJ . d(-1) less than estima ted EE. The 24-h EE, REE, SEE, and SPA of the LOW athletes were signif icantly lower than the ADQ athletes (862, 523, 770 kJ . d(-1), and 43 min . d(-1), respectively). Using all subjects, there was a significan t positive correlation between REE and free thyroxine (FT4) (r = 0.82) and SEE and FT4 (r = 0.66). Thus, part of the LOW athlete's ability t o maintain body weight on a seemingly low energy intake appears due to a lower daily sedentary EE.