title: Metabolic Equivalent in Adolescents, Active Adults and Pregnant Women.
abstract: "Metabolic Equivalent" (MET) represents a standard amount of oxygen consumed by the body under resting conditions, and is defined as 3.5 mL O₂/kg × min or ~1 kcal/kg × h. It is used to express the energy cost of physical activity in multiples of MET. However, universal application of the 1-MET standard was questioned in previous studies, because it does not apply well to all individuals. Height, weight and resting metabolic rate (RMR, measured by indirect calorimetry) were measured in adolescent males (n = 50) and females (n = 50), women during pregnancy (gestation week 35-41, n = 46), women 24-53 weeks postpartum (n = 27), and active men (n = 30), and were compared to values predicted by the 1-MET standard. The RMR of adolescent males (1.28 kcal/kg × h) was significantly higher than that of adolescent females (1.11 kcal/kg × h), with or without the effects of puberty stage and physical activity levels. The RMR of the pregnant and post-pregnant subjects were not significantly different. The RMR of the active normal weight (0.92 kcal/kg × h) and overweight (0.89 kcal/kg × h) adult males were significantly lower than the 1-MET value. It follows that the 1-MET standard is inadequate for use not only in adult men and women, but also in adolescents and physically active men. It is therefore recommended that practitioners estimate RMR with equations taking into account individual characteristics, such as sex, age and Body Mass Index, and not rely on the 1-MET standard.
authors.affiliation: Swiss Federal Institute of Sport, Magglingen 2532, Switzerland. katarina.melzer@baspo.admin.ch.
authors.forename: Katarina
authors.initials: K
authors.lastname: Melzer
authors.affiliation: Swiss Federal Institute of Sport, Magglingen 2532, Switzerland. Juliane.Heydenreich@baspo.admin.ch.|Institute of Sports Science (ISSUL), Faculty of Biology and Medicine, University of Lausanne, Lausanne 1015, Switzerland. Juliane.Heydenreich@baspo.admin.ch.
authors.forename: Juliane
authors.initials: J
authors.lastname: Heydenreich
authors.affiliation: Faculty of Biology and Medicine, Department of Physiology, University of Lausanne, Lausanne 1015, Switzerland &amp; Integrative Cardiovascular and Metabolic Physiology, University of Fribourg, Fribourg 1700, Switzerland. Yves.Schutz@unifr.ch.
authors.forename: Yves
authors.initials: Y
authors.lastname: Schutz
authors.affiliation: Swiss Federal Institute of Sport, Magglingen 2532, Switzerland. Anne.Renaud@baspo.admin.ch.
authors.forename: Anne
authors.initials: A
authors.lastname: Renaud
authors.affiliation: Institute of Sports Science (ISSUL), Faculty of Biology and Medicine, University of Lausanne, Lausanne 1015, Switzerland. Bengt.Kayser@unil.ch.
authors.forename: Bengt
authors.initials: B
authors.lastname: Kayser
authors.affiliation: Swiss Federal Institute of Sport, Magglingen 2532, Switzerland. Urs.Maeder@baspo.admin.ch.
authors.forename: Urs
authors.initials: U
authors.lastname: Mäder
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging; D001481:Basal Metabolism; D015992:Body Mass Index; D002648:Child; D004734:Energy Metabolism; D015444:Exercise; D005260:Female; D006801:Humans; D007774:Lactation / Q000378:metabolism*; D008297:Male; D050177:Overweight / Q000378:metabolism*; D010101:Oxygen Consumption; D049590:Postpartum Period; D011247:Pregnancy / Q000378:metabolism*; D011263:Pregnancy Trimester, Third; D015203:Reproducibility of Results; D012727:Sex Characteristics; D013557:Switzerland; D013851:Thinness / Q000378:metabolism*; D055815:Young Adult
keywords: active men; adolescents; metabolic equivalent; physical activity; pregnant women; resting metabolic rate