Energy availability discriminates clinical menstrual status in exercising women

FieldValue
dc.contributor.authorReed, Jennifer L
dc.contributor.authorDe Souza, Mary J
dc.contributor.authorMallinson, Rebecca J
dc.contributor.authorScheid, Jennifer L
dc.contributor.authorWilliams, Nancy I
dc.date.accessioned2015-12-18T10:55:44Z
dc.date.available2015-12-18T10:55:44Z
dc.date.issued2015-02-19
dc.identifier.citationJournal of the International Society of Sports Nutrition. 2015 Feb 19;12(1):11
dc.identifier.urihttp://dx.doi.org/10.1186/s12970-015-0072-0
dc.identifier.urihttp://hdl.handle.net/10393/33747
dc.description.abstractAbstract Background Conditions of low energy availability (EA) (<30 kcal/kgLBM) have been associated with suppressed metabolic hormones and reductions in LH pulsatility in previously sedentary women during short-term manipulations of energy intake (EI) and exercise energy expenditure (EEE) in a controlled laboratory setting. The purpose of this study was to examine if EA, defined as EA = (EI-EEE)/kgLBM, is associated with disruptions in ovarian function in exercising women. Methods Menstrual status was confirmed with daily measures of urinary reproductive metabolites across 1–3 menstrual cycles or 28-day monitoring periods. EA was calculated for exercise days using EI from 3-day diet logs, EEE from heart-rate monitors and/or exercise logs for a 7-day period, and body composition from DXA. Resting energy expenditure (REE) was measured by indirect calorimetry. Total triiodothyronine (TT3) was measured from a fasting blood sample. Results 91 exercising women (23.1 ± 0.5 years) were categorized clinically as either exercising amenorrheic (ExAmen, n = 30), exercising oligomenorrheic (ExOligo, n = 20) or exercising eumenorrheic (ExEumen, n = 41). The eumenorrheic group was further divided into more specific subclinical groups as either exercising ovulatory (ExOv, n = 20), exercising inconsistent (ExIncon, n = 13), or exercising anovulatory (ExAnov, n = 8). An EA threshold of 30 kcal/kgLBM did not distinguish subclinical menstrual status (χ 2 = 0.557, p = 0.46) nor did EA differ across subclinical disturbance groups (p > 0.05). EA was lower in the ExAmen vs. ExEumen (30.9 ± 2.4 vs. 36.9 ± 1.7 kcal/kgLBM, p = 0.04). The ratio of REE/predicted REE was lower in the ExAmen vs. ExEumen (0.85 ± 0.02 vs. 0.92 ± 0.01, p = 0.001) as was TT3 (79.6 ± 4.1 vs. 95.3 ± 2.9 ng/mL, p = 0.002). Conclusions EA did not differ among subclinical forms of menstrual disturbances in a large sample of exercising women, but EA did discriminate clinical menstrual status, i.e., amenorrhea from eumenorrhea.
dc.titleEnergy availability discriminates clinical menstrual status in exercising women
dc.typeJournal Article
dc.date.updated2015-12-18T10:55:44Z
dc.language.rfc3066en
dc.rights.holderReed et al.; licensee BioMed Central.
CollectionLibre accès - Publications // Open Access - Publications

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