Effect of Preexercise Ingestion of Modified Amylomaize Starch on Glycemic Response While Cycling.

Amylomaize-7 is classified as a resistant corn starch and is 68% digestible. When modified by partial hydrolysis in ethanol and hydrochloric acid its digestibility is 92%, yet retains its low glycemic and insulinemic properties. The purpose of this study was to characterize the metabolic response when modified amylomaize-7 or dextrose is consumed in the hour before exercise, and to compare the effect on performance of a brief high-intensity cycling trial. Ten male, trained cyclists were given 1 g/kg body mass of dextrose (DEX) or modified amylomaize-7 (AMY-7) or a flavored water placebo (PL) 45 min prior to exercise on a cycle ergometer. A 15-min ride at 60% Wmax was immediately followed by a self-paced time trial (TT) equivalent to 15 min at 80% Wmax. When cyclists consumed DEX, mean serum glucose concentration increased by 3.3 ± 2.1 mmol/L before exercise, compared to stable serum glucose observed for AMY-7 or PL. Glucose concentrations returned to baseline by pre-TT in all treatments. However, the mean post-TT glucose concentration of the DEX group was significantly lower than baseline, AMY-7, or PL. Serum insulin concentration increased nine-fold from baseline to preexercise in the DEX trial, whereas PL or AMY-7 remained unchanged. Time required to complete the performance trial was not significantly different between DEX, AMY-7 or PL. Preexercise ingestion of modified amylomaize-7 compared to dextrose resulted in a more stable serum glucose concentration, but did not offer a performance advantage in this high-intensity cycling trial.

Iron Deficiency and Anemia among Collegiate Athletes: A Retrospective Chart Review.

PURPOSE: To describe the prevalence of anemia among incoming female college athletes and to characterize the results and expenses of iron-related testing at one National Collegiate Athletic Association Division I institution. METHODS: In this retrospective medical record review, hemoglobin (Hgb) and ferritin laboratory values were obtained for student-athletes at a single institution, 2002 to 2014. Laboratories were collected either as part of the preparticipation examination (PPE) for female athletes, routine screening for cross-country athletes, or as needed for medical evaluation. Anemia was defined as Hgb < 11.6 g·dL for females and < 13.6 g·dL for male athletes. Iron deficiency was defined as Fer < 20 ng·mL for both sexes. RESULTS: A total of 5674 laboratory draws were obtained for 2749 individuals (56% female) from 25 different teams. The prevalence of low Hgb among female athletes at PPE was 5.7% (95% confidence interval, 4.4%-6.9%). At PPE, the incidence of anemia was not significantly higher for any sport when compared with the group mean. Ferritin and Hgb were collected together in approximately one third of all blood draws from females (n = 1059) and one sixth of blood draws from males (n = 411). For female athletes, 2.2% indicated iron deficiency anemia and 30.9% indicated iron deficiency without anemia. For male athletes, 1.2% indicated iron deficiency anemia and 2.9% indicated iron deficiency without anemia. The median cost of iron testing exceeded US $20,000 annually for the institution. CONCLUSIONS: One in 20 incoming female athletes was identified with anemia at the PPE. Given the costs of testing, screening practices at each institution should be thoughtfully selected and routinely reassessed.

Developing a Performance Nutrition Curriculum for Collegiate Athletics.

The purpose of this article is to provide a framework for developing a sports nutrition education program in a collegiate athletic department. A review of literature on student-athlete nutrition behaviors is combined with practical suggestions from personnel who wrote a sports nutrition curriculum at a large Midwestern university. There are 2 primary implications for practice. First, maintaining a written curriculum and conducting periodic evaluation are fundamental aspects of sports nutrition education programs. Second, better documentation of program outcomes is needed to establish best practices in collegiate sports nutrition education and demonstrate the value of full-time sports registered dietitians.