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The Segal fatness-specific bioelectrical impedance (BIA) equations are useful for predicting fat-free mass (FFM). Stolarczyk et al, proposed a modified method of averaging the two equations for individuals who are neither lean nor obese, thus eliminating the need to know % BF a priori. To cross-validate this modification, we compared FFM determined using the averaging method versus hydrostatic weighing for 76 adults. Per the averaging method, accuracy for males was excellent (r = .91, SEE = 2.7kg, E = 2.7kg), with 78% of individuals within ± 3.5% BF predicted by hydrostatic weighing. Accuracy for females was lower (r = .88, SEE = 3.0kg, E = 3.1 kg), with %BF of 51% within ±3.5% of the reference method. The relative ease and practicality of the averaging method and the results of this study indicate this method may be useful with a diverse group.

The purpose of this study was to determine the dietary adequacy of 12 collegiate cross-country runners during a competitive season. Four-day diet records were collected twice during the season and analyzed for total daily energy, macronutrients, vitamin A, vitamin C, thiamin, riboflavin, niacin, vitamin ${\text{B}}_6$ , folate, iron, magnesium, zinc, and calcium. Mean energy intake (3,248 ± 590 kcal) was not significantly different from estimated mean energy expenditure (3,439 ± 244 kcal). Week 8 mean prealbumin levels were within normal limits (26.8 ± 2.8 mg/dl). Mean daily CHO intake was 497 ± 134 g/day (61.2%). Three to four hours prior to competition a pre-race meal was consumed; it contained 82 ± 47 g CHO. Posteompetition CHO intake was delayed an average 2.5 hr; at that time approximately 2.6 ± 0.69 g CHO/kg body weight was consumed. The athletes appeared to demonstrate dietary adequacy with the exception of timing of posteompetition carbohydrate consumption.

A survey was used to collect anonymous cross-sectional data on demographics, exercise habits, and use of creatine and other supplements by exercisers in civilian (C) and military (M) health clubs. M (n = 133) reported more aerobic training and less use of creatine and protein supplements than C(n = 96, p < .05). Supplement users (SU, n = 194) and nonusers (SNU, n = 35) engaged in similar frequency and duration of aerobic exercise, as well as number of resistance exercise repetitions, but SU completed more sets for each resistance exercise (x̄ ± SE, 5 ± 1) than SNU (3 ± 1, p ≤ .05). Significant (p ≤ .05) associations were observed between SU and resistance training goal of strength (as opposed to endurance), as well as greater frequency of resistance training. Male gender, resistance training goal of strength, lower frequency and duration of aerobic training, and use of protein, ß-hydroxy-ß-methyl butyrate, and androstenedi-one/dehydroepiandrosterone supplements were all associated with creatine use (p < .05). For creatine users, the dose and length of creatine supplementation was 12.2±2.7g•day^·1 for 40 ± 5 weeks. Popular magazines were the primary source of information on creatine (69%) compared to physicians (14%) or dietitians (10%, p ≤ .0001). This study underscores two potential public health concerns: (a) reliance on popular media rather than allied-health professionals for information on creatine, and (b) use of creatine, a popular supplement with unknown long-term effects, in combination with other anabolic supplements of questionable efficacy and/or safety.

Low bone-mineral density (BMD) is associated with menstrual dysfunction and negative energy balance in the female athlete triad. This study determines BMD in elite female endurance runners and the associations between BMD, menstrual status, disordered eating, and training volume. Forty-four elite endurance runners participated in the cross-sectional study, and 7 provided longitudinal data. Low BMD was noted in 34.2% of the athletes at the lumbar spine, and osteoporosis in 33% at the radius. In cross-sectional analysis, there were no significant relationships between BMD and the possible associations. Menstrual dysfunction, disordered eating, and low BMD were coexistent in 15.9% of athletes. Longitudinal analysis identified a positive association between the BMD reduction at the lumbar spine and training volume (p = .026). This study confirms the presence of aspects of the female athlete triad in elite female endurance athletes and notes a substantial prevalence of low BMD and osteoporosis. Normal menstrual status was not significantly associated with normal BMD, and it is the authors’ practice that all elite female endurance athletes undergo dual-X-ray absorptiometry screening. The association between increased training volume, trend for menstrual dysfunction, and increased loss of lumbar BMD may support the concept that negative energy balance contributes to bone loss in athletes.

Secretory IgA in saliva (s-IgA) is a potential mucosal immune correlate of upper respiratory tract infection (URTI) status. Nutritional supplements may improve mucosal immunity, and could be beneficial to athletes who are at increased risk of URTI. In this study, 35 distance runners (15 female, 20 male, age 35 to 58 y) consumed a supplement of either bovine colostrum or placebo for 12 wk. Saliva samples were taken prior to training at baseline, monthly during supplementation, and 2 wk post supplementation. Median levels of s-IgA increased by 79% in the colostrum group after 12 wk intervention, and the time-dependent change from baseline value was significant (P = 0.0291). This significance was still apparent after adjusting for training volume and self-reporting of upper respiratory symptoms. This study has demonstrated increased s-IgA levels among a cohort of athletes following colostrum supplementation. While this result is statistically significant, its physiological interpretation must be viewed with caution due to the small numbers in this study and the large variability in s-IgA levels.