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Rebecca T. Viner, Margaret Harris, Jackie R. Berning and Nanna L. Meyer

The purpose of this study was to assess energy availability (EA) and dietary patterns of 10 adult (29–49 years) male (n = 6) and female (n = 4) competitive (USA Cycling Category: Pro, n = 2; 1–4, n = 8) endurance cyclists (5 road, 5 off-road), with lower than expected bone mineral density (BMD; Z score < 0) across a season. Energy intake (EI) and exercise energy expenditure during preseason (PS), competition (C), and off-season (OS) were estimated from 3-day dietary records, completed once per month, across a cycling season. BMD was measured by DXA at 0 months/5 months/10 months. The Three-Factor Eating Questionnaire (TFEQ) was used to assess cognitive dietary restraint. Seventy percent of participants had low EA [(LEA); < 30 kcal·kg fat-free mass (FFM)−1·day−1] during PS, 90% during C, and 80% during OS (range: 3–37 kcal·kg FFM−1·day−1). Ninety percent of cyclists had LEA during ≥ 1 training period, and 70% had LEA across the season. Seventy percent of cyclists were identified as restrained eaters who consciously restrict EI as a means of weight control. Mean daily carbohydrate intake was below sport nutrition recommendations during each training period (PS: 3.9 ± 1.1 g·kg−1·day−1, p < .001; C: 4.3 ± 1.4 g·kg−1·day−1, p = .005; OS: 3.7 ± 1.4 g·kg−1·day−1, p = .01). There were no differences in EA and EI·kg−1 between male and female cyclists and road and off-road cyclists. Low EI, and specifically low carbohydrate intake, appears to be the main contributor to chronic LEA in these cyclists. Adult male and female competitive road and off-road cyclists in the United States may be at risk for long-term LEA. Further studies are needed to explore strategies to prevent and monitor long-term LEA in these athletes.

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George Wilson, Dan Martin, James P. Morton and Graeme L. Close

The relative energy deficiency in sport (RED-S) syndrome was recently developed in recognition that male athletes display evidence of impaired physiological function that may be related to low energy availability ( Mountjoy et al., 2014 ). Jockeys are unique among professional athletes in that they

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Sarah Staal, Anders Sjödin, Ida Fahrenholtz, Karen Bonnesen and Anna Katarina Melin

Ballet dancers are reported to have an increased risk for low energy availability (EA) with or without disordered eating (DE) behavior or eating disorders ( Doyle-Lucas et al., 2010 ; Lagowska et al., 2014 ; Nattiv et al., 2007 ). Energy deficiency is related to impaired performance and a wide

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Paula B. Costa, Scott R. Richmond, Charles R. Smith, Brad Currier, Richard A. Stecker, Brad T. Gieske, Kimi Kemp, Kyle E. Witherbee and Chad M. Kerksick

high physical training load, increased anxiety, and emotional stress in conjunction with insufficient energy intake (EI) may result in a scenario where low energy availability (EA) persists in this population. 3 Training in an environment that is weight supported with reduced mechanical loading

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Sherry Robertson and Margo Mountjoy

components—that is, low energy availability (LEA), menstrual dysfunction (MD), and low bone mineral density (BMD) ( Nattiv et al., 2007 ). The International Olympic Committee (IOC) Consensus Group coined the more comprehensive term, RED-S, to more accurately describe the pathophysiology and multisystem

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Monica Klungland Torstveit, Ida Fahrenholtz, Thomas B. Stenqvist, Øystein Sylta and Anna Melin

 al., 2008 ; Gibbs et al., 2013 ; Melin et al., 2015 ). Traditionally, energy status is evaluated in blocks of 24-hr as either energy balance (EB = energy intake − total energy expenditure) or energy availability (EA = energy intake − exercise energy expenditure [EEE] relative to fat-free mass [FFM

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Charlotte P. Guebels, Lynn C. Kam, Gianni F. Maddalozzo and Melinda M. Manore

It is hypothesized that exercise-related menstrual dysfunction (ExMD) results from low energy availability (EA), defined as energy intake (EI)—exercise energy expenditure (EEE). When EI is too low, resting metabolic rate (RMR) may be reduced to conserve energy.

Purpose:

To measure changes in RMR and EA, using four methods to quantify EEE, before/after a 6-month diet intervention aimed at restoring menses in women with ExMD; eumenorrheic (Eumen) active controls (n = 9) were also measured.

Methods:

Active women with ExMD (n = 8) consumed +360 kcal/d (supplement) for 6 months; RMR was measured 2 times at 0 months/6 months. EI and total energy expenditure (TEE) were estimated using 7-day diet/activity records, with EA assessed using four methods to quantify EEE.

Results:

At baseline, groups did not differ for age, gynecological age, body weight, lean/fat mass, VO2max, EI and EA, but mean TEE was higher in ExMD (58.3 ± 4.4kcal/kgFFM/d; Eumen = 50.6 ± 2.4; p < .001) and energy balance (EB) more negative (–10.3 ± 6.9 kcal/kgFFM/d; Eumen=-3.0 ± 9.7; p = .049). RMR was higher in ExMD (31.3 ± 1.8 kcal/kgFFM/d) vs. Eumen (29.1 ± 1.9; p < .02). The intervention increased weight (1.6 ± 2.0kg; p = .029), but there were no significant changes in EA (0-month range = 28.2–36.7 kcal/kgFFM/d; 6-month range = 30.0–45.4; p > .05), EB (6 months = –0.7 ± 15.1 kcal/kgFFM/d) or RMR (0 months = 1515 ± 142; 6 months = 1522 ± 134 kcal/d). Assessment of EA varied dramatically (~30%) by method used.

Conclusions:

For the ExMD group, EI and weight increased with +360 kcal/d for 6 months, but there were no significant changes in EB, EA or RMR. No threshold EA value was associated with ExMD. Future research should include TEE, EB and clearly quantifying EEE (e.g.,>4 MET) if EA is measured.

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Hans Braun, Judith von Andrian-Werburg, Wilhelm Schänzer and Mario Thevis

of the EE of all recorded activities. Further, the energy availability (EA), which is defined as [energy intake (kcal) − exercise energy expenditure (kcal)]/lean body mass (kg), was calculated. EA is categorized as insufficient when <30 kcal/kg lean body mass (LBM) are consumed ( 38 , 50

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Trent Stellingwerff

contemporary nutrition recommendations ( Stellingwerff et al., 2011 ) with weight stability and optimal energy availability (EA), were emphasized. Optimal EA is defined as adequate energy intake to cover the energy cost of exercise as well as optimal metabolic function and health ( Mountjoy et al., 2014

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Nancy I. Williams, Clara V. Etter and Jay L. Lieberman

An understanding of the health consequences of abnormal menstrual function is an important consideration for all exercising women. Menstrual disturbances in exercising women are quite common and range in severity from mild to severe and are often associated with bone loss, low energy availability, stress fractures, eating disorders, and poor performance. The key factor that causes menstrual disturbances is low energy availability created by an imbalance of energy intake and energy expenditure that leads to an energy deficit and compensatory metabolic adaptations to maintain energy balance. Practical guidelines for preventing and treating amenorrhea in exercising women include evidence-based dietary practices designed to achieve optimal energy availability. Other factors such as gynecological age, genetics, and one’s susceptibility to psychological stress can modify an individual’s susceptibility to menstrual disturbances caused by low energy availability. Future research should explore the magnitude of these effects in an effort to move toward more individualized prevention and treatment approaches.