The present study was conducted to compare dietary intakes and percentage of body fat between adolescent female runners and sedentary adolescent females. Thirty white girls, aged 15-18 years, served as subjects. Twenty had run between 20 and 55 miles per week for the past 1-5 years. The ten controls had not exercised for at least the past year other than in physical education classes. Nutrient intake was analyzed from 3-day dietary records. Percentage of body fat was estimated using hydrostatic weighing and skinfold thicknesses measured at the right triceps and calf. No significant differences were found between the 20 runners and the 10 controls in intakes of energy, calcium, or iron. Although daily caloric intakes were not higher for the runners, the two groups differed in percentage of body fat; the mean value for the runners was significantly lower than the control group’s value. Both groups consumed greater than recommended percentages of fat and less than recommended percentages of carbohydrates. In addition, both calcium and iron consumptions were below recommended values. In summary, the female runners had typically poor American teenage diets. Overall, these athletes should be instructed to increase their total kilocalories, consume a greater percentage of carbohydrates, and select foods high in calcium and iron.
Susan M. Moen, Charlotte F. Sanborn and Nancy DiMarco
James R. Rowe, Kyle D. Biggerstaff, Vic Ben-Ezra, David L. Nichols and Nancy DiMarco
This study examined the effect of prior exercise on postprandial lipemia (PPL) concentration following a mixed meal (MM) made with either glucose or fructose. Sedentary women completed four trials in random order: 1) Rest-Fructose: RF, 2) Rest-Glucose: RG, 3) Exercise-Fructose: EF, 4) Exercise-Glucose: EG. Exercise expended 500 kcal while walking at 70%VO2max. Rest was 60 min of sitting. The morning after each trial, a fasting (12 hr) blood sample was collected followed by consumption of the MM. The MM was blended with whole milk and ice cream plus a glucose or fructose powder. Glucose and fructose powder accounted for 30% of the total kcal within the MM. Blood was collected periodically for 6 hr post-MM and analyzed for PPL. Magnitude of PPL over the 6 hr postmeal was quantified using the triglyceride incremental area under the curve (TG AUCI). Significant differences (p < .05) between trials were determined using repeated-measures ANOVA and Bonferroni post hoc test. There was no significant difference in the TG AUCI between the four trials (p > .05). A significant trial by time interaction for TG concentration was reported (p < .05). Despite lack of change in the AUCI with prior exercise, the lower TG concentration at multiple time points in the EG trial does indicate that prior exercise has some desirable effect on PPL. This study suggests that replacing fructose with glucose sugars and incorporating exercise may minimize PPL following a mixed meal but exercise will need to elicit greater energy expenditure.