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Bradley C. Nindl, William J. Kraemer, Lincoln A. Gotshalk, James O. Marx, Jeff S. Volek, Jill A. Bush, Keijo Häkkinen, Robert U. Newton and Steve J. Fleck

Regional fat distribution (RFD) has been associated with metabolic derangements in populations with obesity. For example, upper body fat patterning is associated with higher levels of free testosterone (FT) and lower levels of sex-hormone binding globulin (SHBG). We sought to determine the extent to which this relationship was true in a healthy (i.e., non-obese) female population and whether RFD influenced androgen responses to resistance exercise. This study examined the effects of RFD on total testosterone (TT), FT, and SHBG responses to an acute resistance exercise test (ARET) among 47 women (22 ± 3 years; 165 ± 6 cm; 62 ± 8 kg; 25 ± 5 %BF; 23 ± 3 BMI). RFD was characterized by 3 separate indices: waist-to-hip ratio (WHR), ratio of upper arm fat to mid-thigh fat assessed with magnetic resonance imaging (MRI ratio), and ratio of subscapular to triceps ratio (SB/TRi ratio). Skinfolds were measured for the triceps, chest, subscapular, mid-axillary, suprailaic, abdomen, and thigh regions. The ARET consisted of 6 sets of 10 RM squats separated by 2-min rest periods. Blood was obtained pre- and post- ARET. TT, FT, and SHBG concentrations were determined by radioimmunoassay. Subjects were divided into tertiles from the indices of RFD, and statistical analyses were performed by an ANOVA with repeated measures (RFD and exercise as main effects). Significant (p < .05) increases following the AHRET were observed for TT (~25%), FT (~25%), and SHBG (4%). With multiple regression analysis, anthropometric measures significantly predicted pre- concentrations of FT, post-concentrations of TT, and pre-concentrations of SHBG. The SB/TRi and MRI ratios but not the WHR, were discriminant for hormonal concentrations among the tertiles. In young, healthy women, resistance exercise can induce transient increases in testosterone, and anthropometric markers of adiposity correlate with testosterone concentrations.

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Jason D. Vescovi and Jaci L. VanHeest

This observational case study examined the association of inter- and intraday energy intake and exercise energy expenditure with bone health, menstrual status and hematological factors in a female triathlete. The study spanned 7 months whereby energy intake and exercise energy expenditure were monitored three times (13 d); 16 blood samples were taken, urinary hormones were assessed for 3 months, and bone mineral density was measured twice. Energy availability tended to be sustained below 30 kcal/kg FFM/d and intraday energy intake patterns were often “back-loaded” with approximately 46% of energy consumed after 6 p.m. Most triiodothyronine values were low (1.1–1.2nmol/L) and supportive of reduced energy availability. The athlete had suppressed estradiol (105.1 ± 71.7pmol/L) and progesterone (1.79 ±1.19nmol/L) concentrations as well as urinary sex-steroid metabolites during the entire monitoring period. Lumbar spine (L1-L4) bone mineral density was low (age-matched Z-score −1.4 to −1.5). Despite these health related maladies the athlete was able to perform typical weekly training loads (swim: 30–40 km, bike: 120–300 km, run 45–70 km) and was competitive as indicated by her continued improvement in ITU World Ranking during and beyond the assessment period. There is a delicate balance between health and performance that can become blurred especially for endurance athletes. Education (athletes, coaches, parents) and continued monitoring of specific indicators will enable evidence-based recommendations to be provided and help reduced the risk of health related issues while maximizing performance gains. Future research needs to longitudinally examine how performance on standardized tests in each discipline (e.g., 800-m swim, 20-km time trial, 5-km run) is impacted when aspects of the female athlete triad are present.

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Jenny Meggs, Mark Chen and Danielle Mounfield

puberty ( Manning, Scutt, Wilson, & Lewis-Jones, 1998 ). Researchers have suggested possible causal factors for these differences including sex steroids could influence relative bone lengths by facilitating the development of phalangeal anlagen during the perinatal period or metaphyseal growth

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María Reyes Beltran-Valls, Enrique García Artero, Ana Capdevila-Seder, Alejandro Legaz-Arrese, Mireia Adelantado-Renau and Diego Moliner-Urdiales

associated with increased sports injuries in adolescent athletes . J Pediatr Orthop . 2014 ; 34 ( 2 ): 129 – 33 . PubMed doi:10.1097/BPO.0000000000000151 10.1097/BPO.0000000000000151 25028798 35. Mong JA , Cusmano DM . Sex differences in sleep: impact of biological sex and sex steroids . Philos

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Jeremiah J. Peiffer, Chris R. Abbiss, Eric C. Haakonssen and Paolo Menaspà

of road sprinting in professional and U23 cycling. A pilot study . J Sci Cycling . 2013 ; 2 : 35 – 39 . 21. Sato K , Iemitsu M . Exercise and sex steroid hormones in skeletal muscle . J Steroid Biochem Mol Biol . 2015 ; 145 : 200 – 205 . PubMed ID: 24704257 doi:10.1016/j.jsbmb.2014

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Aurora de Fátima G.C. Mafra Cabral, Marcelo Medeiros Pinheiro, Charlles H.M. Castro, Marco Túlio De Mello, Sérgio Tufik and Vera Lúcia Szejnfeld

disorders, cardiovascular disease, diabetes mellitus, neurological or musculoskeletal disease, or medication that interferes with ambulation (including sedatives and antidepressant drugs), malignancies, use of sex steroids, and renal or hepatic impairment were excluded from the present study. Participants

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Mauricio Castro-Sepulveda, Jorge Cancino, Rodrigo Fernández-Verdejo, Cristian Pérez-Luco, Sebastian Jannas-Vela, Rodrigo Ramirez-Campillo, Juan Del Coso and Hermann Zbinden-Foncea

transmembrane regulator (CFTR) and sodium hydrogen exchanger (NHE) in vas deferens of sex-steroid deficient male rats . Steroids, 138 , 117 – 133 . PubMed ID: 30003911. doi:10.1016/j.steroids.2018.06.012 10.1016/j.steroids.2018.06.012 Lara , B. , Gallo-Salazar , C. , Puente , C. , Areces , F

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Guilherme M. Cesar, Rebecca Lewthwaite and Susan M. Sigward

: Insights from anatomical magnetic resonance imaging . Neuroscience & Biobehavioral Reviews, 30 , 718 – 729 . PubMed doi:10.1016/j.neubiorev.2006.06.001 10.1016/j.neubiorev.2006.06.001 Mauras , N. ( 2001 ). Growth hormone and sex steroids: Interactions in puberty . Endocrinology and Metabolism

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Charity B. Breneman, Christopher E. Kline, Delia West, Xuemei Sui and Xuewen Wang

differences in sleep: Impact of biological sex and sex steroids . Philosophical Transactions of the Royal Society of London B: Biological Sciences, 371 , 20150110 . PubMed ID: 26833831 doi:10.1098/rstb.2015.0110 10.1098/rstb.2015.0110 Morss , G.A. , Jordan , A.N. , Skinner , J.S. , Dunn , A

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Youngdeok Kim, Joaquin U. Gonzales and P. Hemachandra Reddy

Project FRONTIER study . BMC Musculoskeletal Disorders, 17 ( 1 ), 181 . doi: 10.1186/s12891-016-1042-7 Brown , M. ( 2008 ). Skeletal muscle and bone: Effect of sex steroids and aging . Advances in Physiology Education, 32 ( 2 ), 120 – 126 . PubMed ID: 18539850 doi: 10.1152/advan.90111