title: Daily energy expenditure in male endurance athletes with differing energy intakes.
abstract: The 24-h energy expenditure (24-h EE), resting EE (REE), sleeping EE (SEE), and spontaneous physical activity (SPA) were compared between six male endurance athletes whose reported energy intake was low (LOW) and did not match that theoretically required for weight maintenance and four whose reported energy intake appeared adequate (ADQ) and matched their estimated EE. Groups did not differ in age, body weight, fat-free mass, and daily EE estimated from activity records. The LOW athletes reported an energy intake 6338 +/- 2164 kJ.d-1 less than estimated EE. The 24-h EE, REE, SEE, and SPA of the LOW athletes were significantly lower than the ADQ athletes (862, 523, 770 kJ.d-1, and 43 min.d-1, respectively). Using all subjects, there was a significant 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 to maintain body weight on a seemingly low energy intake appears due to a lower daily sedentary EE.
authors.affiliation: Exercise and Sport Research Institute, Arizona State University, Tempe 85287, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Thompson
authors.forename: M M
authors.initials: MM
authors.lastname: Manore
authors.forename: J S
authors.initials: JS
authors.lastname: Skinner
authors.forename: E
authors.initials: E
authors.lastname: Ravussin
authors.forename: M
authors.initials: M
authors.lastname: Spraul
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D001481:Basal Metabolism / Q000502:physiology; D001823:Body Composition; D001824:Body Constitution; D001835:Body Weight; D004032:Diet; D002149:Energy Intake; D004734:Energy Metabolism / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D010807:Physical Endurance / Q000502:physiology*; D012890:Sleep / Q000502:physiology; D013177:Sports / Q000502:physiology*; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
chemical_list: D014284:Triiodothyronine; D013974:Thyroxine