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Association Between Energy Balance and Metabolic Hormone Suppression During Ultraendurance Exercise

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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Low Energy Availability Is Difficult to Assess but Outcomes Have Large Impact on Bone Injury Rates in Elite Distance Athletes

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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Upper-Body Resistance Training Following Soccer Match Play: Compatible, Complementary, or Contraindicated?

Angelo Sabag, Ric Lovell, Neil P. Walsh, Nick Grantham, Mathieu Lacome, and Martin Buchheit

review was to evaluate the current evidence and factors, including neuromuscular, metabolic, hormonal, perceptual, and immunological components, that may contribute to the suitability of scheduling UB RT on MD+1 with a view to providing preliminary recommendations (eg, compatible, complementary, or

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Endocrinology and Metabolism

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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Pitfalls of Conducting and Interpreting Estimates of Energy Availability in Free-Living Athletes

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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Case Study: Energy Availability and Endocrine Markers in Elite Male Track Cyclists

Katherine L. Schofield, Holly Thorpe, and Stacy T. Sims

), with a ratio of <0.90 as a marker of energy defiency. 11 pRMR was estimated using the Cunningham equation. 12 Table 1 Body-Composition, Metabolic, Hormonal, Dietary, and EA Characteristics in Elite Male Track Cyclists (N = 4) Athlete Body fat, % FFM, kg RMR, kcal/d RMR ratio LH, U/L Total T, nmol

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Endocrine Effects of Relative Energy Deficiency in Sport

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

. , & Williams , N.I. ( 2004 ). Fasting ghrelin levels in physically active women: Relationship with menstrual disturbances and metabolic hormones . The Journal of Clinical Endocrinology and Metabolism, 89 ( 7 ), 3536 – 3542 . PubMed ID: 15240643 doi:10.1210/jc.2003-032007 De Souza , M.J. , Luciano , A

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A Narrative Review on Female Physique Athletes: The Physiological and Psychological Implications of Weight Management Practices

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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Prevalence of Surrogate Markers of Relative Energy Deficiency in Male Norwegian Olympic-Level Athletes

Thomas Birkedal Stenqvist, Anna Katarina Melin, Ina Garthe, Gary Slater, Gøran Paulsen, Juma Iraki, Jose Areta, and Monica Klungland Torstveit

linear relationship was found between RMR ratio and surrogate biochemical markers of RED-S ( p  > .05). Table 4 Reproductive and Metabolic Hormones of Athletes in Total and Categorized According to Energetic Status Measurement Total ( n  = 44) Low RMR ( n  = 7) Normal RMR ( n  = 37) p value ES (95% CI

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Diurnal Variation of Maximal Fat-Oxidation Rate in Trained Male Athletes

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