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Katherine A. Beals and Amanda K. Hill

The purpose of this study was to examine the prevalence of disordered eating (DE), menstrual dysfunction (MD), and low bone mineral density (BMD) among US collegiate athletes (n = 112) representing 7 different sports (diving, swimming, x-country, track, tennis, field hockey, and softball) and determine differences in prevalence existed between athletes participating in lean-build (LB) and non-lean build (NLB) sports. DE and MD were assessed by a health, weight, dieting, and menstrual history questionnaire. Spinal BMD was determined via dual energy x-ray absorptiometry. Twenty-eight athletes met the criteria for DE, twenty-nine for MD, and two athletes had low BMDs (using a Z score below −2.0). Ten athletes met the criteria for two disorders (one with disordered eating and low BMD and nine with disordered eating and menstrual dysfunction), while only one athlete met the criteria for all three disorders. Using a Z score below −1.0, two additional athletes met the criteria for all three disorders and three more athletes met the criteria for a combination of two disorders. With the exception of MD, which was significantly more prevalent among LB vs. NLB sports (P = 0.053), there were no differences between the groups in the prevalence of individual disorders or combinations of disorders. These data indicate that the combined prevalence of DE, MD, and low BMD among collegiate athletes is small; however, a significant number suffer from individual disorders of the Triad.

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Stacy D. Hunter, Mandeep S. Dhindsa, Emily Cunningham, Takashi Tarumi, Mohammed Alkatan, Nantinee Nualnim and Hirofumi Tanaka

Background:

Obesity is associated with arterial stiffening and diminished quality of life. Bikram yoga may be a feasible alternative to traditional exercise among obese individuals. Accordingly, the purpose of this study was to investigate the impact of Bikram yoga, a heated style of hatha yoga, on arterial stiffness in normal and overweight/obese adults.

Methods:

Forty-three (23 normal body mass index or BMI; 20 overweight/obese) apparently healthy participants completed an 8-week Bikram yoga intervention. Body composition was estimated via dual energy x-ray absorptiometry, arterial stiffness was measured via brachialankle pulse wave velocity, and health-related quality of life was assessed via RAND 36-Item Short Form survey at baseline and at the end of the 8-week intervention.

Results:

After the intervention, brachial-ankle pulse wave velocity decreased (P < .05) in overweight/obese participants while no such changes were observed in normal BMI participants. In the quality of life measures, emotional well-being improved (P < .05) in both groups, and general health improved (P < .05) only in the normal weight BMI group.

Conclusion:

Bikram yoga ameliorates arterial stiffness in overweight/obese adults and can positively impact quality of life regardless of BMI.

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Peter N. Wiebe, Cameron J.R. Blimkie, Nathalie Farpour-Lambert, Julie Briody, Helen Woodhead, Chris Cowell and Robert Howman-Giles

The correlates and determinants of total body (TB), femoral neck (FN), greater trochanter (GT) and leg areal bone mineral density (aBMD), and FN volumetric (vol) BMD were investigated in 42 healthy 6–10-year-old girls. Predictor variables included age, height, weight, lean tissue mass (LTM), fat mass, percent body fat, physical activity level, calcium intake, isokinetic knee flexion and extension strength and endocrine (E2) status. Bone density and body composition were determined by dual energy-x-ray absorptiometry (DEXA), and pubertal status was self-determined. LTM, weight, age, knee extensor strength and fat mass were significantly correlated (Pearson correlation coefficients; 0.36 £ r ‡ 0.62) with TBaBMD. These same variables with the addition of height and knee flexor strength were significantly correlated (0.33 £ r ‡ 0.77) with leg aBMD. Only LTM correlated significantly with FNaBMD and none of the independent variables correlated with FNvolBMD or GTaBMD. Only LTM entered as a significant predictor in multiple linear regression analysis (R 2 = 46.7%) for TBaBMD. In conclusion, estradiol status, dietary calcium intake and physical activity level appeared not to be important predictors of BMD in this population, whereas LTM was consistently correlated with most BMD measures and was the single significant determinant of TBaBMD in this study.

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Ana Anton-Solanas, Barry V. O’Neill, Tessa E. Morris and Joe Dunbar

Purpose:

To assess changes in body composition and monitor cognitive function, subjective well-being, and physiological stress, as measured by salivary hormones and markers of mucosal immunity, during an Antarctic expedition.

Methods:

A 36-y-old man (188.2 cm height, 94.5 kg body mass) took part in a world-record attempt. A total-body dual-energy X-ray absorptiometry scan and measurement of 8 skinfolds and 5 girths were performed before and after the expedition. In addition, daily subjective data were recorded (sleep quality, total hours of sleep, energy levels, perceived exertion, mood, muscle soreness, and muscle/joint pain) along with distance covered and hours of physical activity per day. As a measure of cognitive function, the athlete completed a computerized battery of tasks (Axon Sports Cognitive Priming Application) every third morning. Saliva samples were collected before, during, and after the expedition to determine salivary cortisol (sCort), testosterone (sT), alpha amylase (sAA), and secretory immunoglobulin A (sIgA).

Results:

The athlete lost 5.3 kg body mass and sum of 8 skinfolds decreased from 73 mm to 59 mm from preexpedition to postexpedition. Psychomotor speed declined over the course of the expedition. sT increased and sCort decreased throughout, and sAA and sIgA peaked toward the end of the expedition.

Conclusions:

This case study provides novel data about the physiological and cognitive impact of an Antarctic expedition. The findings may inform strategies for future expeditions, allowing individuals undertaking expeditions of this nature to better prepare for success.

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Johann C. Bilsborough, Thomas Kempton, Kate Greenway, Justin Cordy and Aaron J. Coutts

Purpose:

To compare development and variations in body composition of early-, mid-, and late-career professional Australian Football (AF) players over 3 successive seasons.

Methods:

Regional and total-body composition (body mass [BM], fat mass [FM], fat-free soft-tissue mass [FFSTM], and bone mineral content [BMC]) were assessed 4 times, at the same time of each season—start preseason (SP), end preseason (EP), midseason (MS), and end season (ES)—from 22 professional AF players using pencil-beam dual-energy X-ray absorptiometry. Nutritional intake for each player was evaluated concomitantly using 3-d food diaries. Players were classified according to their age at the beginning of the observational period as either early- (<21 y, n = 8), mid- (21 to 25 y, n = 9), or late- (>25 y, n = 5) career athletes.

Results:

Early-career players had lower FFSTM, BMC, and BM than mid- and late-career throughout. FM and %FM had greatest variability, particularly in the early-career players. FM reduced and FFSTM increased from SP to EP, while FM and FFSTM decreased from EP to MS. FM increased and FFSTM decreased from MS to ES, while FM and FFSTM increased during the off-season.

Conclusions:

Early-career players may benefit from greater emphasis on specific nutrition and resistance-training strategies aimed at increasing FFSTM, while all players should balance training and diet toward the end of season to minimize increases in FM.

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Heidi L. Petersen, C. Ted Peterson, Manju B. Reddy, Kathy B. Hanson, James H. Swain, Rick L. Sharp and D. Lee Alekel

This study determined the effect of training on body composition, dietary intake, and iron status of eumenorrheic female collegiate swimmers (n = 18) and divers (n = 6) preseason and after 16 wk of training. Athletes trained on dryland (resistance, strength, fexibility) 3 d/wk, 1.5 h/d and in-water 6 d/wk, nine, 2-h sessions per week (6400 to 10,000 kJ/d). Body-mass index (kg/m2; P = 0.05), waist and hip circumferences (P ≤ 0.0001), whole body fat mass (P = 0.0002), and percentage body fat (P ≤ 0.0001) decreased, whereas lean mass increased (P = 0.028). Using dual-energy X-ray absorptiometry, we found no change in regional lean mass, but fat decreased at the waist (P = 0.0002), hip (P = 0.0002), and thigh (P = 0.002). Energy intake (10,061 ± 3617 kJ/d) did not change, but dietary quality improved with training, as refected by increased intakes of fber (P = 0.036), iron (P = 0.015), vitamin C (P = 0.029), vitamin B-6 (P = 0.032), and fruit (P = 0.003). Iron status improved as refected by slight increases in hemoglobin (P = 0.046) and hematocrit (P = 0.014) and decreases in serum transferrin receptor (P ≤ 0.0001). Studies are needed to further evaluate body composition and iron status in relation to dietary intake in female swimmers.

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Alex S. Ribeiro, Brad J. Schoenfeld, Danilo R.P. Silva, Fábio L.C. Pina, Débora A. Guariglia, Marcelo Porto, Nailza Maestá, Roberto C. Burini and Edilson S. Cyrino

The purpose of this study was to compare different split resistance training routines on body composition and muscular strength in elite bodybuilders. Ten male bodybuilders (26.7 ± 2.7 years, 85.3 ± 10.4 kg) were randomly assigned into one of two resistance training groups: 4 and 6 times per week (G4× and G6×, respectively), in which the individuals trained for 4 weeks, 4 sets for each exercise performing 6–12 repetitions maximum (RM) in a pyramid fashion. Body composition was assessed by dual energy X-ray absorptiometry, muscle strength was evaluated by 1RM bench-press testing. The food intake was planned by nutritionists and offered individually throughout the duration of the experiment. Significant increases (p < .05) in fat-free mass (G4× = +4.2%, G6× = +3.5%) and muscular strength (G4× = +8.4%, G6× = +11.4%) with no group by time interaction were observed. We conclude that 4 and 6 weekly sessions frequencies of resistance training promote similar increases in fat-free mass and muscular strength in elite bodybuilders.

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Gary Slater, David Jenkins, Peter Logan, Hamilton Lee, Matthew Vukovich, John A. Rathmacher and Allan G. Hahn

This investigation evaluated the effects of oral β-Hydroxy-β-Methylbutyrate (HMB) supplementation on training responses in resistance-trained male athletes who were randomly administered HMB in standard encapsulation (SH), HMB in time release capsule (TRH), or placebo (P) in a double-blind fashion. Subjects ingested 3 g · day−1 of HMB or placebo for 6 weeks. Tests were conducted pre-supplementation and following 3 and 6 weeks of supplementation. The testing battery assessed body mass, body composition (using dual energy x-ray absorptiometry), and 3-repetition maximum isoinertial strength, plus biochemical parameters, including markers of muscle damage and muscle protein turnover. While the training and dietary intervention of the investigation resulted in significant strength gains (p < .001) and an increase in total lean mass (p = .01), HMB administration had no influence on these variables. Likewise, biochemical markers of muscle protein turnover and muscle damage were also unaffected by HMB supplementation. The data indicate that 6 weeks of HMB supplementation in either SH or TRH form does not influence changes in strength and body composition in response to resistance training in strength-trained athletes.

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Alessandra Madia Mantovani, Scott Duncan, Jamile Sanches Codogno, Manoel Carlos Spiguel Lima and Rômulo Araújo Fernandes

Background:

Physical activity level is an important tool to identify individuals predisposed to developing chronic diseases, which represent a major concern worldwide.

Objective:

To identify correlates of daily step counts measured using pedometers, as well as analyze the associations between health outcomes and 3 different amounts of daily physical activity.

Methods:

The sample comprised 278 participants (126 men and 153 women) with a mean age of 46.51 ± 9.02 years. Physical activity was assessed using pedometers for 7 consecutive days, and 3 amounts of daily physical activity were considered: ≥10,000 steps/day, ≥7500 steps/day, and <5000 steps/day. Sleep quality was assessed through a questionnaire, and dual-energy x-ray absorptiometry was used to measure body fat. Sociodemographic and anthropometric data were also collected.

Results:

The percentages of adults achieving at least 10,000 and 7500 steps/day on a minimum of 5 days of the evaluated week were 12.9% and 30.9%, respectively. Adults who reached ≥7500 steps/day had a lower likelihood of being obese (odds ratio [OR] = 0.38, 95% confidence interval [CI], 0.17–0.85) and reporting worse sleep quality (OR = 0.58, 95% CI, 0.34–0.99). Adults who reached <5000 steps/day had a higher likelihood of reporting worse sleep quality (OR = 2.11, 95% CI, 1.17–3.82).

Conclusion:

Physical activity in adulthood, as measured by pedometer, constituted a behavior related to lower adiposity and better sleep quality.

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Darren G. Candow, Natalie C. Burke, T. Smith-Palmer and Darren G. Burke

The purpose was to compare changes in lean tissue mass, strength, and myof-brillar protein catabolism resulting from combining whey protein or soy protein with resistance training. Twenty-seven untrained healthy subjects (18 female, 9 male) age 18 to 35 y were randomly assigned (double blind) to supplement with whey protein (W; 1.2 g/kg body mass whey protein + 0.3 g/kg body mass sucrose power, N = 9: 6 female, 3 male), soy protein (S; 1.2 g/kg body mass soy protein + 0.3 g/kg body mass sucrose powder, N = 9: 6 female, 3 male) or placebo (P; 1.2 g/kg body mass maltodextrine + 0.3 g/kg body mass sucrose powder, N = 9: 6 female, 3 male) for 6 wk. Before and after training, measurements were taken for lean tissue mass (dual energy X-ray absorptiometry), strength (1-RM for bench press and hack squat), and an indicator of myofbrillar protein catabolism (urinary 3-methylhistidine). Results showed that protein supplementation during resistance training, independent of source, increased lean tissue mass and strength over isocaloric placebo and resistance training (P < 0.05). We conclude that young adults who supplement with protein during a structured resistance training program experience minimal beneficial effects in lean tissue mass and strength.