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Bjoern Geesmann, Jenna C. Gibbs, Joachim Mester and Karsten Koehler

Ultraendurance athletes often accumulate an energy deficit when engaging in ultraendurance exercise, and on completion of the exercise, they exhibit endocrine changes that are reminiscent of starvation. However, it remains unclear whether these endocrine changes are a result of the exercise per se or secondary to the energy deficit and, more important, whether these changes can be attenuated by increased dietary intake. The goal of the study was to assess the relationship between changes in key metabolic hormones after ultraendurance exercise and measures of energy balance. Metabolic hormones, as well as energy intake and expenditure, were assessed in 14 well-trained male cyclists who completed a 1230-km ultraendurance cycling event. After completion of the event, serum testosterone (–67% ± 18%), insulin-like growth factor-1 (IGF-1) (–45% ± 8%), and leptin (–79% ± 9%) were significantly suppressed (P < .001) and remained suppressed after a 12-h recovery period (P < .001). Changes in IGF-1 were positively correlated with energy balance over the course of the event (r = .65, P = .037), which ranged from an 11,859-kcal deficit to a 3593-kcal surplus. The marked suppression of testosterone, IGF-1, and leptin after ultraendurance exercise is comparable to changes occurring during acute starvation. The suppression of IGF-1, but not that of other metabolic hormones, was strongly associated with the magnitude of the energy deficit, indicating that athletes who attained a greater energy deficit exhibited a more pronounced drop in IGF-1. Future studies are needed to determine whether increased dietary intake can attenuate the endocrine response to ultraendurance exercise.

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Ida A. Heikura, Arja L.T. Uusitalo, Trent Stellingwerff, Dan Bergland, Antti A. Mero and Louise M. Burke

metabolic hormone ( Koehler et al., 2016 ) levels, albeit likely at a lower threshold than females (20–25 kcal·kg −1 fat-free mass [FFM]·day −1 ; Fagerberg, 2017 ). Furthermore, it is noteworthy that despite significant reductions (10–40%) in TES levels due to low EA ( Tenforde et al., 2016 ) have been

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Alon Eliakim

Introduction:

Competitive female athletes restrict energy intake and increase exercise energy expenditure frequently resulting in ovarian suppression. The purpose of this study was to determine the impact of ovarian suppression and energy deficit on swimming performance (400-m swim velocity).

Methods:

Menstrual status was determined by circulating estradiol (E2) and progesterone (P4) in ten junior elite female swimmers (15-17 yr). The athletes were categorized as cyclic (CYC) or ovarian-suppressed (OVS). They were evaluated every 2 weeks for metabolic hormones, bioenergetic parameters, and sport performance during the 12-week season.

Results:

CYC and OVS athletes were similar (p > .05) in age (CYC = 16.2 ± 1.8 yr, OVS = 17 ± 1.7 yr), body mass index (CYC = 21 ± 0.4 kg·m, OVS = 25 ± 0.8 kg·m), and gynecological age (CYC = 2.6 ± 1.1 yr, OVS = 2.8 ± 1.5 yr). OVS had suppressed P4 (p < .001) and E2 (p = .002) across the season. Total triiodothyronine (TT3) and insulin-like growth factor (IGF-1) were lower in OVS (TT3: CYC = 1.6 ± 0.2 nmol·L, OVS = 1.4 ± 0.1 nmol·L, p < .001; IGF-1: CYC = 243 ± 1 μg·mL, OVS = 214 μg·mL p < .001) than CYC at week 12. Energy intake (p < .001) and energy availability (p < .001) were significantly lower in OVS versus CYC. OVS exhibited a 9.8% decline in Δ400-m swim velocity compared with an 8.2% improvement in CYC at week 12.

Conclusions:

Ovarian steroids (P4 and E2), metabolic hormones (TT3 and IGF-1), and energy status markers (EA and EI) were highly correlated with sport performance. This study illustrates that when exercise training occurs in the presence of ovarian suppression with evidence for energy conservation (i.e., reduced TT3), it is associated with poor sport performance. These data from junior elite female athletes support the need for dietary periodization to help optimize energy intake for appropriate training adaptation and maximal sport performance

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Louise M. Burke, Bronwen Lundy, Ida L. Fahrenholtz and Anna K. Melin

concentrations or pulsatility (the amplitude and frequency of the oscillations in concentrations) of metabolic hormones (e.g., insulin, insulin-like growth factor 1, leptin, triiodothyronine; and reproductive hormones (e.g., estradiol, gonadotropin-releasing hormone, luteinizing hormone) and interfere with

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Nura Alwan, Samantha L. Moss, Kirsty J. Elliott-Sale, Ian G. Davies and Kevin Enright

, 1994 ). Changes to reproductive and metabolic hormones in FP athletes have been observed in the precompetition phase, including decreases in estradiol, testosterone, thyroid-stimulating hormone, triiodothyronine, and leptin (Table  1 ). These hormones were normalized within 4–16 weeks postcompetition

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Kirsty J. Elliott-Sale, Adam S. Tenforde, Allyson L. Parziale, Bryan Holtzman and Kathryn E. Ackerman

doi:10.1016/j.fertnstert.2006.11.171 10.1016/j.fertnstert.2006.11.171 De Souza , M.J. , Leidy , H.J. , O’Donnell , E. , Lasley , B. , & Williams , N.I. ( 2004 ). Fasting ghrelin levels in physically active women: Relationship with menstrual disturbances and metabolic hormones . The Journal

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Sarah Kölling, Rob Duffield, Daniel Erlacher, Ranel Venter and Shona L. Halson

example, the high physical and mental stress imposed as part of normal athlete training and competition routines requires appropriate recovery time to facilitate adaptive processes. Given the role of sleep in metabolic, hormonal, and cognitive regeneration from daily activities when awake, 2 , 3

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Francisco J. Amaro-Gahete, Lucas Jurado-Fasoli, Alejandro R. Triviño, Guillermo Sanchez-Delgado, Alejandro De-la-O, Jørn W. Helge and Jonatan R. Ruiz

endurance exercise performed in the morning and evening on inflammatory cytokine and metabolic hormone responses . PLoS One . 2015 ; 10 : e0137567 . 10.1371/journal.pone.0137567 26352938 10. Darvakh H , Nikbakht M , Shakerian S , Mousavian AS . Effect of circadian rhythm on peak of maximal

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Anna K. Melin, Ida A. Heikura, Adam Tenforde and Margo Mountjoy

disruption to metabolic hormones ( Heikura et al., 2018 ; Koehler et al., 2013 ) and menstrual dysfunction ( Melin et al., 2015 ; Williams et al., 2015 ). Initially, LEA leads to a negative energy balance and thereby weight loss because the body’s energy reserves (e.g., adipose tissue and body proteins

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Ulrika Andersson-Hall, Stefan Pettersson, Fredrik Edin, Anders Pedersen, Daniel Malmodin and Klavs Madsen

starvation . The Journal of Physiology, 325 , 363 – 376 . PubMed doi:10.1113/jphysiol.1982.sp014155 10.1113/jphysiol.1982.sp014155 McMurray , R.G. , & Hackney , A.C. ( 2005 ). Interactions of metabolic hormones, adipose tissue and exercise . Sports Medicine, 35 ( 5 ), 393 – 412 . PubMed doi:10