Diane M. DellaValle

Children's binge eating and development of metabolic syndrome

Background:Binge eating predisposes children to excessive weight gain. However, it is unknown if pediatric binge eating predicts other obesity-associated adverse health outcomes.Objective:The objective of this study was to investigate the relationship between binge eating and metabolic syndrome (MetS) in children.Method:Children aged 5–12 years at high risk for adult obesity, either because they were overweight/obese when first examined or because their parents were overweight/obese, were recruited from Washington, DC and its suburbs. Children completed a questionnaire assessment of binge eating at baseline and underwent measurements of MetS components at baseline and at a follow-up visit approximately 5 years later. Magnetic resonance imaging was used to measure the visceral adipose tissue (VAT) in a subset.Results:In all, 180 children were studied between July 1996 and August 2010. Baseline self-reported binge eating presence was associated with a 5.33 greater odds of having MetS at follow-up (95% confidence interval (CI): 1.47, 19.27, P=0.01). The association between binge eating and body mass index (BMI) only partially explained changes in MetS components: baseline binge eating predicted higher follow-up triglycerides, even after accounting for baseline triglycerides, baseline BMI, BMI change, sex, race, baseline age and time in study (P=0.05). Also, adjusting for baseline VAT and demographics, baseline binge eating predicted greater follow-up L2−3 VAT (P=0.01).Discussion:Childrens reports of binge eating predicted development of MetS, worsening triglycerides and increased VAT. The excessive weight gain associated with childrens binge eating partly explained its adverse metabolic health outcomes. Reported binge eating may represent an early behavioral marker upon which to focus interventions for obesity and MetS.

Iron supplementation for female athletes: effects on iron status and performance outcomes.

Iron is an essential micronutrient involved in oxidative metabolism and critical to exercise performance. The prevalence of iron deficiency (ID) is much higher in active women for a variety of reasons, and poor iron status has been shown to be detrimental to overall health as well as physical performance. Iron status can be assessed using a number of indicators; however clinical cut-offs for active populations remain controversial. Randomized, placebo-controlled supplementation trials of iron-depleted female athletes have shown that oral iron supplementation in doses of 100-mg FeSO4·d−1 (approximately 20 mg elemental iron) improves iron status and may improve measures of physical performance. It is recommended that female athletes most at risk of ID be screened at the beginning of and during the training season using hemoglobin and serum ferritin, and appropriate dietary and/or supplementation recommendations be made to those with compromised iron status.

Iron supplementation improves energetic efficiency in iron-depleted female rowers.

PURPOSE Studies in both animals and humans show a relationship between iron depletion without anemia (IDNA) and physical performance. Compared with their sedentary counterparts, female endurance athletes are at greater risk of IDNA, and consequences relevant to endurance athletes include reduced work capacity and energetic efficiency (EF). We conducted a randomized placebo-controlled trial to investigate the effects of iron (Fe) supplementation on Fe status and performance in nonanemic female rowers during training. METHODS At the beginning of a training season, 40 rowers were randomized to receive either 100 mg·d FeSO4 (n = 21) or placebo (n = 19) using a double-blind design. Thirty-one (n = 15 Fe, 16 placebo) completed the 6-wk trial. Fe status (hemoglobin, serum ferritin, soluble transferrin receptor), body composition, and laboratory tests of physical performance (4-km time trial, V˙O2peak, energetic EF, and blood lactate) were assessed at baseline and after training. RESULTS Rowers in both groups increased their fat-free mass (P < 0.001) and V˙O2peak (P < 0.001) after training. Multiple regression analyses revealed improvements in Fe stores (serum ferritin) in the Fe treatment group after controlling for baseline Fe stores (P = 0.07). Rowers in the Fe group had slower lactate response during the first half of the time trial and after 5 min of recovery (P = 0.05) and showed greater improvements in energy expenditure (P = 0.01 for group-by time) and energetic EF compared with placebo (P = 0.03 for group-by time). CONCLUSIONS Female rowers with depleted Fe stores who consumed supplemental Fe during training improved their Fe status and energetic EF during endurance exercise. These results are important for endurance athletes whose dietary patterns and physical training increase their risk of IDNA and suggest that Fe supplementation may maximize the benefits of endurance training.

Quantification of training load and intensity in female collegiate rowers: validation of a daily assessment tool.

Abstract DellaValle, DM and Haas, JD. Quantification of training load and intensity in female collegiate rowers: Validation of a daily assessment tool. J Strength Cond Res 27(2): 540–548, 2013—Session rating of perceived exertion (RPE) has been used to quantify a variety of training activities but has not been tested in rowers, who engage in intermittent patterns of activity. The objective of this study was to evaluate the ability of the subjective session RPE method to quantify on- and off-water rowing training load (TL) compared with a heart rate (HR) summation method. Seven female collegiate rowers (19.7 ± 0.8 years) were monitored during 2 workout simulations differing in intensity level in the laboratory and several training sessions outside of the laboratory. Training load was calculated using an HR summation method, and RPE was measured after the completion of each simulation or training activity (session RPE). During the workout simulations, despite poor correlation between the HR summation and session RPE methods (r = −0.21, p = 0.52), the session RPE method was significantly correlated with peak WR (r = 0.59, p = 0.05) and posttest blood lactate concentration (r = 0.73, p = 0.007). During training sessions outside of the laboratory, the HR summation (280.7 ± 108.3) and session RPE (6,432.5 ± 4,002.0) methods were highly correlated (r = 0.88, p < 0.001). Regression analyses revealed that after controlling for time, training intensity rating was a significant predictor of TL (p < 0.001). We conclude that the session RPE method is a valid metric of TL in female rowers. The methods convenience renders it a feasible option for researchers and coaches to quantify and monitor TL in rowers.

Randomized trial of nutrition education added to internet-based information and exercise at the work place for weight loss in a racially diverse population of overweight women

Objective:Obesity in the United States is highly prevalent, approaching 60% for black women. We investigated whether nutrition education sessions at the work place added to internet-based wellness information and exercise resources would facilitate weight and fat mass loss in a racially diverse population of overweight female employees.Methods:A total of 199 (average body mass index 33.9±6.3 kg m−2) nondiabetic women (57% black) at our institution were randomized to a 6-month program of either internet-based wellness information (WI) combined with dietitian-led nutrition education group sessions (GS) weekly for 3 months and then monthly with shift in emphasis to weight loss maintenance (n=99) or to WI alone (n=100). All were given access to exercise rooms convenient to their work site. Fat mass was measured by dual-energy X-ray absorptiometry.Results:WI+GS subjects lost more weight than WI subjects at 3 months (−2.2±2.8 vs −1.0±3.0 kg, P>0.001). Weight (−2.7±3.9 vs −2.0±3.9 kg) and fat mass (−2.2±3.1 vs −1.7±3.7 kg) loss at 6 months was significant for WI+GS and WI groups (both P<0.001), but without significant difference between groups (both P>0.10); 27% of the WI+GS group achieved ⩾5% loss of initial weight as did 18% of the WI group (P=0.180). Blacks and whites similarly completed the study (67 vs 74%, P=0.303), lost weight (−1.8±3.4 vs −3.3±5.2 kg, P=0.255) and fat mass (−1.6±2.7 vs −2.5±4.3 kg, P=0.532), and achieved ⩾5% loss of initial weight (21 vs 32%, P=0.189), irrespective of group assignment.Conclusion:Overweight women provided with internet-based wellness information and exercise resources at the work site lost weight and fat mass, with similar achievement by black and white women. Additional weight loss benefit of nutrition education sessions, apparent at 3 months, was lost by 6 months and may require special emphasis on subjects who fail to achieve weight loss goals to show continued value.

Relationship between physical activity, physical performance, and iron status in adult women

Iron deficiency affects approximately 16% of US females 18-45 years old. Iron is a key component of heme-containing proteins, which are essential for oxygen transport throughout the body. With low iron levels, performance and intense physical activity may be compromised. Thus, the purpose of this study was to examine the relationship between iron status, physical performance, and physical activity in 18- to 45-year-old females. Participants (N = 109) were screened for iron status using a venous blood sample, had their height and mass measured, and self-reported their physical activity level. The screening was used to match iron-depleted nonanemic females (hemoglobin, Hgb > 120 g·L(-1); serum ferritin, sFer < 20 µg·L(-1)) to females with normal iron levels. After participant matching, they had their body composition measured, performed three cycle ergometer tests (maximal, endurance, and efficiency), and wore an ActiGraph GT1M accelerometer for five consecutive days, except when sleeping or during water activities. The final sample consisted of 25 iron-depleted participants and 24 with normal iron levels. Key findings were as follows: (i) after controlling for fat-free mass and vigorous physical activity, iron-depleted females had a significantly lower [Formula: see text]O(2) at ventilatory threshold compared with those with normal iron levels (P < 0.05); and (ii) after controlling for age, iron-depleted females spent significantly more time in sedentary behaviors and significantly less time in light physical activity than those with normal iron levels (P < 0.05). The increased sedentary time in iron-depleted females may contribute to excess mass gain over time; however, further investigation is needed to confirm these results.