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Eric T. Trexler, Katie R. Hirsch, Bill I. Campbell and Abbie E. Smith-Ryan

The purpose of the current study was to evaluate changes in body composition, metabolic rate, and hormones during postcompetition recovery. Data were collected from natural physique athletes (7 male/8 female) within one week before (T1) competition, within one week after (T2), and 4–6 weeks after (T3) competition. Measures included body composition (fat mass [FM] and lean mass [LM] from ultrasongraphy), resting metabolic rate (RMR; indirect calorimetry), and salivary leptin, testosterone, cortisol, ghrelin, and insulin. Total body water (TBW; bioelectrical impedance spectroscopy) was measured at T1 and T2 in a subsample (n = 8) of athletes. Significant (p < .05) changes were observed for weight (T1 = 65.4 ± 12.2 kg, T2 = 67.4 ± 12.6, T3 = 69.3 ± 13.4; T3 > T2 > T1), LM (T1 = 57.6 ± 13.9 kg, T2 = 59.4 ± 14.2, T3 = 59.3 ± 14.2; T2 and T3 > T1), and FM (T1 = 7.7 ± 4.4 kg, T2 = 8.0 ± 4.4, T3 = 10.0 ± 6.2; T3 > T1 and T2). TBW increased from T1 to T2 (Δ=1.9 ± 1.3 L, p < .01). RMR increased from baseline (1612 ± 266 kcal/day; 92.0% of predicted) to T2 (1881 ± 329, 105.3%; p < .01) and T3 (1778 ± 257, 99.6%; p < .001). Cortisol was higher (p < .05) at T2 (0.41 ± 0.31 μg/dL) than T1 (0.34 ± 0.31) and T3 (0.35 ± 0.27). Male testosterone at T3 (186.6 ± 41.3 pg/mL) was greater than T2 (148.0 ± 44.6, p = .04). RMR changes were associated (p ≤ .05) with change in body fat percent (ΔBF%; r = .59) and T3 protein intake (r= .60); male testosterone changes were inversely associated (p≤ .05) with ΔBF%, ΔFM, and Δweight (r=-0.81–-0.88). TBW increased within days of competition. Precompetition RMR suppression appeared to be variable and markedly reversed by overfeeding, and reverted toward normal levels following competition. RMR and male testosterone increased while FM was preferentially gained 4–6 weeks postcompetition.

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Andrew Pardue, Eric T. Trexler and Lisa K. Sprod

Extreme body composition demands of competitive bodybuilding have been associated with unfavorable physiological changes, including alterations in metabolic rate and endocrine profile. The current case study evaluated the effects of contest preparation (8 months), followed by recovery (5 months), on a competitive drug-free male bodybuilder over 13 months (M1-M13). Serum testosterone, triiodothyronine (T3), thyroxine (T4), cortisol, leptin, and ghrelin were measured throughout the study. Body composition (BodPod, dualenergy x-ray absorptiometry [DXA]), anaerobic power (Wingate test), and resting metabolic rate (RMR) were assessed monthly. Sleep was assessed monthly via the Pittsburgh Sleep Quality Index (PSQI) and actigraphy. From M1 to M8, testosterone (623–173 ng∙dL-1), T3 (123–40 ng∙dL-1), and T4 (5.8–4.1 mg∙dL-1) decreased, while cortisol (25.2–26.5 mg∙dL-1) and ghrelin (383–822 pg∙mL-1) increased. The participant lost 9.1 kg before competition as typical energy intake dropped from 3,860 to 1,724 kcal∙day-1; BodPod estimates of body fat percentage were 13.4% at M1, 9.6% at M8, and 14.9% at M13; DXA estimates were 13.8%, 5.1%, and 13.8%, respectively. Peak anaerobic power (753.0 to 536.5 Watts) and RMR (107.2% of predicted to 81.2% of predicted) also decreased throughout preparation. Subjective sleep quality decreased from M1 to M8, but objective measures indicated minimal change. By M13, physiological changes were largely, but not entirely, reversed. Contest preparation may yield transient, unfavorable changes in endocrine profile, power output, RMR, and subjective sleep outcomes. Research with larger samples must identify strategies that minimize unfavorable adaptations and facilitate recovery following competition.

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R. Scott Van Zant

Maintenance of a healthy body weight results from equating total enegy intake to total energy expenditure (resting metabolic rate, RMR, the thermic effect of feeding, TEF; the thermic effect of activity, TEA, and adaptive thermogenesis, AT). Dietary quantity and composition and acute and chrvnic exercise have been shown to influence all components of total energy expenditure. This paper reviews the effects of exercise and diet on energy expenditure and, ultimately, energy balance. Overnutrition increases RMR and TEF while undernutrition decreases them. Carbohydrate and protein oxidation is closely tied to intake whereas fat oxidation does not closely parallel fat intake. Thus excess fat intake is likely to lead to fat storage. Acute endurance exercise at >70% VO2max increases postexercise RMR and TEF. Chronic exercise training may increase RMR while also increasing TEF. Review of the research indicates that energy balance may best be achieved by consuming an energy appropriate, low fat diet complemented by endurance exercise.

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

athletes younger than 18 years should be avoided. Periodization of EA across days or weeks and within day may be useful weight-loss strategies because periodic increases in EA theoretically counteract adaptive thermogenesis, enabling further weight loss ( Trexler et al., 2014 ), although contrary findings

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mass (11.4kg-6.5kg). Lean body mass remained constant (54.5-55.0kg) and RMR was generally stable (1710 ± 77-1602 ± eliciting minimal adaptive thermogenesis. The final 1.8kg of BM loss (2.8%) was achieved 24 hours prior to weigh in utilising active/passive dehydration methods. Despite LEA