A high fiber diet intervention during pregnancy: The SPROUT (Single goal in PRegnancy to optimize OUTcomes) protocol paper.

BACKGROUND: Interventions to prevent excessive gestational weight gain (GWG) have had a limited impact on maternal and infant outcomes. Dietary fiber is a nutrient with benefits that counters many of the metabolic and inflammatory changes that occur during pregnancy. We will determine if a high dietary fiber (HFib) intervention provides benefit to maternal and infant outcomes. METHODS AND DESIGN: Pregnant women will be enrolled in an 18-week intervention and randomized in groups of 6-10 women/group into the intervention or control group. Weekly lessons will include information on high-dietary fiber foods and behavior change strategies. Women in the intervention group will be given daily snacks high in dietary fiber (10-12 g/day) to facilitate increasing dietary fiber intake. The primary aim will assess between-group differences for the change in maternal weight, dietary fiber intake, dietary quality, and body composition during pregnancy and up to two months post-partum. The secondary aim will assess between-group differences for the change in maternal weight, dietary fiber intake, and dietary quality from two months to one year post-partum and infant body composition from birth to one-year-old. DISCUSSION: Effective and simple intervention strategies to improve maternal and offspring outcomes are lacking. Changes during the perinatal period are related to the risk of disease development in the mother and offspring. However, it is unknown which changes can be successfully targeted to have a meaningful impact. We will test the effect of an intervention designed to counter many of the metabolic and inflammatory changes that occur during pregnancy. ETHICS AND DISSEMINATION: The University of Kansas Medical Center Institutional Review Board (IRB) approved the study protocol (STUDY00145397). The results of the trial will be disseminated at conferences and in peer reviewed publications. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT04868110.

Growth and adiposity in newborns study (GAINS): The influence of prenatal DHA supplementation protocol.

BACKGROUND: Obesity and central fat mass (FM) accrual drive disease development and are related to greater morbidity and mortality. Excessive gestational weight gain (GWG) increases fetal fat accretion resulting in greater offspring FM across the lifespan. Studies associate greater maternal docosahexaenoic acid (DHA) levels with lower offspring FM and lower visceral adipose tissue during childhood, however, most U.S. pregnant women do not consume an adequate amount of DHA. We will determine if prenatal DHA supplementation is protective for body composition changes during infancy and toddlerhood in offspring exposed to excessive GWG. METHODS AND DESIGN: Infants born to women who participated in the Assessment of DHA on Reducing Early Preterm Birth randomized controlled trial (ADORE; NCT02626299) will be invited to participate. Women were randomized to either a high 1000 mg or low 200 mg daily prenatal DHA supplement starting in the first trimester of pregnancy. Offspring body composition and adipose tissue distribution will be measured at 2 weeks, 6 months, 12 months, and 24 months using dual energy x-ray absorptiometry. Maternal GWG will be categorized as excessive or not excessive based on clinical guidelines. DISCUSSION: Effective strategies to prevent obesity development are lacking. Exposures during the prenatal period are important in the establishment of the offspring phenotype. However, it is largely unknown which exposures can be successfully targeted to have a meaningful impact. This study will determine if prenatal DHA supplementation modifies the relationship between maternal weight gain and offspring FM and FM distribution at 24 months of age. ETHICS AND DISSEMINATION: The University of Kansas Medical Center Institutional Review Board (IRB) approved the study protocol (STUDY00140895). The results of the trial will be disseminated at conferences and in peer reviewed publications. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT03310983.

Calcium, fiber, iron, and sodium intake in adolescents with intellectual and developmental disabilities and overweight and obesity.

BACKGROUND: Adolescents with intellectual and developmental disabilities (IDD) and overweight or obesity (OW/OB) are a nutritionally vulnerable group with increased risk of nutritional deficiencies. However, there are limited data examining micronutrient intake in adolescents with IDD and OW/OB. OBJECTIVE: The purpose of this study was to assess the adequacy of calcium, iron, fiber, and sodium intake referenced against the United States Dietary Reference Intakes in adolescents with IDD and OW/OB. METHODS: Three-day image-assisted food records were used to assess dietary intake of 64 adolescents with IDD and OW/OB. A mean ± standard deviation was calculated for mean intake of calcium (mg), fiber (g/1000 kcals energy), iron (mg), and sodium (mg). RESULTS: A total of 157 nutrient intake observations were completed by 64 participants (56% female, 16.3 ± 2.3 years). Calcium intake for participants ages 14-18 years (n = 57) was 1027.4 ± 607.5 mg, which is below the EAR of 1050 mg. Calcium intake for participants ages ≥19 years (n = 7) was 921.1 ± 596.4 mg, which is greater than the EAR of 840 mg. Fiber intake was 8.4 ± 3.6 g/1000 kcals, which is below the AI of 14 g/1000 kcals. Iron intake for all participants exceeded their respective EARs. Sodium intake was 3180.9 ± 975.9 mg, which above the AI of 2300 mg. CONCLUSION: Calcium intake was adequate for participants ≥19 years of age, but inadequate for participants 14-18 years. For all participants, iron and sodium intake exceeded the DRI while fiber intake was below the DRI.

A prenatal group based phone counseling intervention to improve breastfeeding rates and complementary feeding: a randomized, controlled pilot and feasibility trial.

BACKGROUND: Despite numerous benefits for both mom and baby, few infants are exclusively breastfed for the recommended first six months. Additionally, infants are given solids too early. Prenatal education increases rates of breastfeeding initiation and we hypothesize it can also improve exclusive breastfeeding rates and prevent the early introduction of solids. We conducted a randomized controlled pilot and feasibility trial to understand the feasibility and maternal acceptance of a prenatal behavioral lifestyle intervention (PBLI) delivered via group based phone counseling (GBPC) and its effectiveness on rates of exclusive breastfeeding up to six months postpartum. Secondary aims included rates of any breastfeeding up to six months, rates of early introduction of solids, and infant feeding progression. METHODS: Forty-one pregnant women were recruited from a Kansas City Metropolitan Obstetrics and Gynecology office and randomly assigned to a usual care group or a PBLI. Women in the PBLI participated in six GBPC sessions where they learned about breastfeeding and introducing solids. Feeding questionnaires to assess breastfeeding and introduction of solids were sent at two weeks, two months, four months, and six months postpartum. Structured interviews were also conducted after the intervention and at six months postpartum to assess maternal acceptance and intervention feasibility. RESULTS: Participants overwhelmingly found the intervention acceptable and beneficial. Rates of exclusive breastfeeding and any breastfeeding did not differ between groups at any time point. No between group differences were found for early introduction of solids or infant feeding progression. CONCLUSIONS: Mothers discontinue breastfeeding earlier than recommended despite high rates of initiation. A PBLI delivered via GBP is feasible, acceptable to participants, and showed positive impacts such as maternal empowerment for both breastfeeding and introducing solids. Future interventions should incorporate both prenatal and postpartum components. TRIAL REGISTRATION: Study protocols were approved by the University of Kansas Medical Center's Human Subjects Committee (STUDY00140506) and registered at ClinicalTrials.gov on 02/22/2018 ( NCT03442517 , retrospectively registered). All participants gave written informed consent prior to data collection.

Association Between Added Sugars from Infant Formulas and Rapid Weight Gain in US Infants and Toddlers.

BACKGROUND: Formulas often contain high amounts of added sugars, though little research has studied their connection to obesity. OBJECTIVES: This study assessed the contribution of added sugars from formulas during complementary feeding on total added sugar intakes, and the association between these sugars and upward weight-for-age percentile (WFA%) crossing (i.e., participants crossing a higher threshold percentile were considered to have an upward crossing). METHODS: Data from three 24-hour dietary recalls for infants (n = 97; 9-12 months) and toddlers (n = 44; 13-15 months) were obtained in this cross-sectional analysis. Foods and beverages with added sugars were divided into 17 categories. Pearson's correlations were used to test relations between added sugar intake and upward WFA% crossing, followed by multivariable regressions when significant. ANOVA compared intakes of all, milk-based, and table foods between primarily formula-fed compared with breastfed participants. Multivariable regressions were used to test effects of added sugars and protein from all foods compared with added sugars and protein from milk-based sources on upward WFA% crossing. RESULTS: Added sugars from formulas comprised 66% and 7% of added sugars consumed daily by infants and toddlers, respectively. A significant association was observed between upward WFA% crossing and added sugars from milk-based sources after controlling for gestational age, sex, age, introduction to solid foods, mean energy intakes, and maternal pre-pregnancy BMI and education (ß = 0.003; 95% CI, 0.000-0.007; P = 0.046). Primarily formula-fed participants consumed nearly twice the energy from added sugars (P = 0.003) and gained weight faster (upward WFA% crossing = 1.1 ± 1.2 compared with 0.3 ± 0.6, respectively; P < 0.001) than their breastfed counterparts. CONCLUSIONS: Added sugars in formulas predict rapid weight gain in infants and toddlers. Educating mothers on lower-sugar options may enhance childhood obesity prevention.

Intermittent and continuous energy restriction result in similar weight loss, weight loss maintenance, and body composition changes in a 6 month randomized pilot study.

Poor adherence is a barrier to successful weight control. Intermittent energy restriction (IER) provides an alternative approach to those for whom daily energy restriction is not ideal. This study assessed changes in weight, body composition, and macronutrient intake for an IER and a continuous energy restriction (CONT) approach within a multicomponent weight management intervention. We randomized 35 adults with overweight/obesity (BMI = 31.2 ± 2.4 kg/m2 ) to CONT or IER for 24 weeks (12-week weight loss intervention and 12 weeks of weight loss maintenance). Diets were delivered within a multimodal weight management program including weekly group meetings with a registered dietitian, increased physical activity, and a comprehensive lifestyle change program. Retention and adherence were similar for CONT and IER. Weight, BMI, fat mass, percentage body fat, waist circumference, hip circumference, blood pressure, and heart rate all decreased after 24 weeks (all, P < .01), but there were no main effects of group (all, P > .27). Weight loss was clinically relevant in both CONT (11.38 ± 7.9%) and IER (9.37 ± 9.7%), and the proportion of each group achieving 5% weight loss was 82 and 61% (P = .16), respectively. Participant satisfaction was high in both groups. The results from this study (a) support the feasibility of IER as an alternative for weight loss and weight loss maintenance, (b) indicate that IER is an effective alternative to CONT for weight control and improvements in body composition, and (c) emphasize the importance of intensive lifestyle interventions with ongoing support for effective behaviour modification.

The effect of high dietary fiber intake on gestational weight gain, fat accrual, and postpartum weight retention: a randomized clinical trial.

BACKGROUND: Interventions to prevent excessive gestational weight gain (GWG) have had limited success This pilot study examined the effectiveness of a single goal (SG) high dietary fiber intervention to prevent excessive GWG. METHODS: Twelve weekly lessons focused on consuming a high fiber diet (≥30 g/day). Snacks containing 10-12 g of dietary fiber were given for the first 6 weeks only. Body composition was measured at baseline and at the end of the intervention. At one-year postpartum, body weight retention and dietary practices were assessed. A p-value is reported for the primary analysis only. For all other comparisons, Cohen's d is reported to indicate effect size. RESULTS: The SG group increased fiber intake during the study (32 g/day at 6 weeks, 27 g/day at 12 weeks), whereas the UC group did not (~ 17 g/day). No differences were found for the proportion of women classified as excessive gainers (p = 0.13). During the intervention, the SG group gained less body weight (- 4.1 kg) and less fat mass (- 2.8 kg) (d = 1.3). At 1 year postpartum, the SG group retained less weight (0.35 vs. 4.4 kg, respectively, d = 1.8), and reported trying to currently eat high fiber foods. CONCLUSION: The SG intervention resulted in less weight gain, fat accrual, and weight retention at 1 year postpartum. A residual intervention effect was detected postpartum with the participants reporting continued efforts to consume a high fiber diet. TRIAL REGISTRATION: NCT03984630; Trial registered June 13, 2019 (retrospectively registered).

Correction to: Validity of anthropometric equations to estimate infant fat mass at birth and in early infancy.

Following the publication of article by Cauble et al. [1], typographical errors were discovered. The Lingwood et al. and Deierlein et al. equations were listed incorrectly. To avoid confusion to the readers, the authors propose to publish a correction. The errors and the corresponding corrections are shown below.

Intrauterine DHA exposure and child body composition at 5 y: exploratory analysis of a randomized controlled trial of prenatal DHA supplementation.

Background: Observational studies find associations between maternal docosahexaenoic acid (DHA) and greater fat-free mass and lower percentage of body fat, but randomized trials of prenatal DHA supplementation have not found significant intent-to-treat effects on childhood body composition. Objective: This study sought to explore associations between intrauterine DHA exposure and body composition and size at 5 y in the offspring of women who participated in a randomized trial of prenatal DHA supplementation (corn and soybean oil placebo or 600 mg/d). Design: At 5 y, body composition was measured by air displacement plethysmography in 154 offspring of women who had participated in the Kansas University DHA Outcomes Study and who had red blood cell (RBC) phospholipid (PL) fatty acids assessed at enrollment and delivery. We used linear regression models to analyze the relation among 3 indicators of intrauterine DHA exposure-1) intent-to-treat (placebo or DHA), 2) maternal RBC PL DHA status at delivery, and 3) change in maternal DHA (delivery minus enrollment)-and 6 outcomes of interest: 5-y fat mass, fat-free mass, percentage of body fat, height, weight, and body mass index z score. Results: Change in maternal RBC PL DHA correlated with higher fat-free mass (r = 0.21, P = 0.0088); the association was unchanged after adjustment for maternal, perinatal, and childhood dietary factors. Intent-to-treat and DHA status at delivery showed positive trends with fat-free mass that were not statistically significant. There was no evidence relating intrauterine DHA exposure to any other body composition measure. Conclusions: Change in maternal DHA status during pregnancy was related to higher offspring 5-y fat-free mass. The other 2 indicators of intrauterine exposure to DHA suggested a trend for higher offspring 5-y fat-free mass. Our findings agree with an earlier observational study from the United Kingdom. This trial was registered at clinicaltrials.gov as NCT00266825.

Programming of infant neurodevelopment by maternal obesity: potential role of maternal inflammation and insulin resistance.

BACKGROUND AND OBJECTIVES: Recent studies show that maternal obesity is associated with impaired offspring neurodevelopmental outcomes. The mechanism underlying the association is unclear. However, there is evidence to suggest a role for intra-uterine exposure to inflammation and insulin resistance (IR). We aimed to determine if maternal IR and inflammation were associated to fetal neurodevelopment as indicated by fetal heart rate variability (HRV), an index of fetal cardiac autonomic nervous system development. METHODS AND STUDY DESIGN: A total of 44 healthy maternal-fetal pairs (maternal pre-pregnancy BMI distribution: n=20 normal weight, 8 overweight, 16 obese) were analyzed. We assessed maternal inflammation (plasma IL-6 and TNF-α) and IR (HOMA index). Fetal HRV, a proxy for fetal neurodevelopment, was assessed using fetal magnetocardiogram at the 36th week of pregnancy. The relationships between maternal inflammation and IR with fetal HRV (SD1 and SD2) were estimated individually by Pearson bivariate correlations. RESULTS: No correlations were observed between the fetal HRV components with maternal HOMA-IR and maternal plasma levels of IL-6 and TNF-α (all p<0.05). However, the negative association between maternal TNF-α level and fetal SD2 approached significance (correlation coefficient=-0.29, 95% confidence interval=-0.62,-0.03, p=0.07). CONCLUSION: Maternal IR and inflammation during pregnancy were not associated with fetal cardiac autonomic nervous system development. Further studies with a larger sample size and more maternal inflammatory indicators are needed to explore these relationships.

Validity of anthropometric equations to estimate infant fat mass at birth and in early infancy.

BACKGROUND: In newborns and children, body fat estimation equations are often used at different ages than the age used to develop the equations. Limited validation studies exist for newborn body fat estimation equations at birth or later in infancy. The study purpose was to validate 4 newborn fat mass (FM) estimation equations in comparison to FM measured by air displacement plethysmography (ADP; the Pea Pod) at birth and 3 months. METHODS: Ninety-five newborns (1-3 days) had their body composition measured by ADP and anthropometrics assessed by skinfolds. Sixty-three infants had repeat measures taken (3 months). FM measured by ADP was compared to FM from the skinfold estimation equations (Deierlein, Catalano, Lingwood, and Aris). Paired t-tests assessed mean differences, linear regression assessed accuracy, precision was assessed by R2 and standard error of the estimate (SEE), and bias was assessed by Bland-Altman plots. RESULTS: At birth, FM measured by ADP differed from FM estimated by Deierlein, Lingwood and Aris equations, but did not differ from the Catalano equation. At 3 months, FM measured by ADP was different from all equations. At both time points, poor precision and accuracy was detected. Bias was detected in most all equations. CONCLUSIONS: Poor agreement, precision, and accuracy were found between prediction equations and the criterion at birth and 3 months.

Relationship of circulating adipokines to body composition in pregnant women.

Circulating adipokines are associated with physiological and pathophysiological processes in both obesity and pregnancy. Obesity in pregnancy increases the risk of pregnancy complications and the majority of research uses body mass index (BMI) to assess fatness. Specific fat compartments are associated with obesity-induced health risks yet it is not known how abdominal fat mass in pregnancy is related to circulating adipokines. Plasma leptin, resistin, visfatin, and adiponectin were measured by immunoassay in healthy pregnant women of normal weight (BMI 18.5-24.9; n = 17) and overweight/obese pregnant women (BMI 25.0-40, n = 21) in the third trimester. Total body and abdominal subcutaneous and visceral fat mass were measured at 1-3 weeks postpartum. Overweight/obese women had greater total body fat (t = -6.210, P < 0.001) and abdominal subcutaneous fat (t = -5.072, P < 0.001) than normal-weight women while there was no difference in abdominal visceral fat. Overweight/obese women had higher leptin (66.3 ± 34.2 vs. 35.7 ± 19.3 ng/mL, P < 0.001) compared to normal-weight women. Leptin was associated with total body fat (r = 0.782, P < 0.001) and resistin was associated with abdominal visceral fat (r = 0.452, P = 0.045). No significant correlations were observed between adiponectin or visfatin and any measure of body composition. In pregnant women, resistin has the potential to be a circulating biomarker for visceral fat, an ectopic fat compartment. These observational data may provide insight for the pathophysiological roles of adipokines and the impact of visceral fat in pregnant women.

Longitudinal body composition of children born to mothers with normal weight, overweight, and obesity.

OBJECTIVE: The longitudinal trajectories of body composition of children born to mothers with normal weight, overweight, and obesity have not been evaluated using precise body composition methods. This study investigated the relationship between maternal prepregnancy BMI and offspring body composition trajectories during the first 6 years of life. METHODS: Healthy infants (N = 325) were assessed longitudinally (at ages 0.25, 0.5, 0.75, 1, 2, 3, 4, 5, and 6 years) using dual-energy X-ray absorptiometry. Mixed-effects regression for repeated measures was used to model each continuous outcome as a function of maternal BMI and covariates (race, gestational age, birth weight, and mode of infant feeding). RESULTS: Maternal obesity differentially impacted body fat, but not bone mineral content or density, of girls and boys. Boys born to mothers with obesity have higher body fat from ages 2-6 years compared to boys born to normal-weight and overweight mothers (P < 0.05), whereas body composition of girls born to mothers with obesity was not different across groups during the first 6 years of life (P > 0.05). CONCLUSIONS: This clinical observational study demonstrates a sexual dimorphism in offspring body composition until age 6 years based on maternal BMI, with a greater effect of maternal adiposity seen in boys than in girls.

Abdominal visceral adiposity influences CD4+ T cell cytokine production in pregnancy.

Women with pre-gravid obesity are at risk for pregnancy complications. While the macrophage response of obese pregnant women categorized by body mass index (BMI) has been documented, the relationship between the peripheral CD4(+) T cell cytokine profile and body fat compartments during pregnancy is unknown. In this study, third trimester peripheral CD4(+) T cell cytokine profiles were measured in healthy pregnant women [n=35; pre-pregnancy BMI: 18.5-40]. CD4(+) T cells were isolated from peripheral blood mononuclear cells and stimulated to examine their capacity to generate cytokines. Between 1 and 3weeks postpartum, total body fat was determined by dual-energy X-ray absorptiometry and abdominal subcutaneous and visceral fat masses were determined by magnetic resonance imaging. Pearson's correlation was performed to assess relationships between cytokines and fat mass. Results showed that greater abdominal visceral fat mass was associated with a decrease in stimulated CD4(+) T cell cytokine expression. IFN-gamma, TNF-alpha, IL-12p70, IL-10 and IL-17A were inversely related to visceral fat mass. Chemokines CCL3 and IL-8 and growth factors G-CSF and FLT-3L were also inversely correlated. Additionally, total body fat mass was inversely correlated with FGF-2 while abdominal subcutaneous fat mass and BMI were unrelated to any CD4(+) T cell cytokine. In conclusion, lower responsiveness of CD4(+) T cell cytokines associated with abdominal visceral fat mass is a novel finding late in gestation.

Higher infant body fat with excessive gestational weight gain in overweight women.

OBJECTIVE: Gestational weight gain (GWG) is positively associated with birthweight and maternal prepregnancy body mass index (BMI) is directly related to infant fat mass (FM). This study examined whether differences exist in infant body composition based on 2009 GWG recommendations. STUDY DESIGN: Body composition was measured in 306 infants, and GWG was categorized as appropriate or excessive. Analysis of covariance was used to investigate the effects of GWG and prepregnancy BMI and their interaction on infant body composition. RESULTS: Within the appropriate group, infants from obese mothers had greater percent fat (%fat) and FM than offspring from normal and overweight mothers. Within the excessive group, infants from normal mothers had less %fat and FM than infants from overweight and obese mothers. A difference was found for %fat and FM within the overweight group between GWG categories. CONCLUSION: Excessive GWG is associated with greater infant body fat and the effect is greatest in overweight women.

The time course of musculotendinous stiffness responses following different durations of passive stretching.

STUDY DESIGN: Repeated-measures experimental design. OBJECTIVE: To examine the acute effects of different durations of passive stretching on the time course of musculotendinous stiffness (MTS) responses in the plantar flexor muscles. BACKGROUND: Stretching is often implemented prior to exercise or athletic competition, with the intent to reduce the risk of injury via decreases in MTS. METHODS AND MEASURES: Twelve subjects (mean +/- SD age, 24 +/- 3 years; stature, 169 +/- 12 cm; mass, 71 +/- 17 kg) participated in 4 randomly-ordered experimental trials: control with no stretching, 2 minutes (2min), 4 minutes (4min), and 8 minutes (8min) of passive stretching. The passive-stretching trials involved progressive repetitions of 30-second passive stretches, while the control trial involved 15 minutes of resting. MTS assessments were conducted before (prestretching), immediately after (poststretching), and at 10, 20, and 30 minutes poststretching on a Biodex System 3 isokinetic dynamometer. RESULTS: MTS decreased (P<.05) immediately after all stretching conditions (2min, 4min, and 8min). However, MTS for the 2min condition returned to baseline within 10 minutes, whereas MTS after the 4min and 8min passive-stretching conditions returned to baseline within 20 minutes. CONCLUSIONS: Practical durations of passive stretching resulted in significant decreases in MTS; however, these changes return to baseline levels within 10 to 20 minutes.

Do practical durations of stretching alter muscle strength? A dose-response study.

PURPOSE: To examine the time course (immediate, 10, 20, and 30 min) for the acute effects of 2, 4, and 8 min of passive stretching (PS) on isometric peak torque (PT), percent voluntary activation (%VA), EMG amplitude, peak twitch torque (PTT), rate of twitch torque development (RTD), and range of motion (ROM) of the plantarflexors. METHODS: Thirteen volunteers (mean +/- SD age, 22 +/- 3 yr) participated in four randomly ordered experimental trials: control (CON) with no stretching, 2 min (PS2), 4 min (PS4), and 8 min (PS8) of PS. Testing was conducted before (pre), immediately after (post), and at 10, 20, and 30 min poststretching. The PS trials involved varied repetitions of 30-s passive stretches, whereas the CON trial included 15 min of resting. PT, %VA, EMG amplitude, PTT, and RTD were assessed during the twitch interpolation technique, whereas ROM was quantified as the maximum tolerable angle of passive dorsiflexion. RESULTS: PT decreased (P < or = 0.05) immediately after all conditions [CON (4%), PS2 (2%), PS4 (4%), and PS8 (6%)] but returned to baseline at 10, 20, and 30 min poststretching. %VA and EMG amplitude were unaltered (P > 0.05) after all conditions. PTT and RTD decreased (P < or = 0.05) immediately after the PS4 (7%) and the PS8 (6%) conditions only; however, these changes were not sufficient to alter voluntary force production. There were also increases (P < or = 0.05) in ROM after the PS2 (8%), the PS4 (14%), and the PS8 (13%) conditions that returned to baseline after 10 min. CONCLUSION: Practical durations of stretching (2, 4, or 8 min) of the plantarflexors did not decrease isometric PT compared with the CON but caused temporary improvements in the ROM, thereby questioning the overall detrimental influence of PS on performance.

Impact of maternal body mass index on neonate birthweight and body composition.

OBJECTIVE: The purpose of this study was to compare bodyweight and composition (percent fat, fat mass, and fat-free mass) in neonates born to mothers with a normal pregravid body mass index (BMI; < 25 kg/m(2)) vs neonates born to mothers with an overweight/obese pregravid BMI (> or = 25 kg/m(2)). STUDY DESIGN: Seventy-two neonates (33 from normal mothers and 39 from overweight/obese mothers) of singleton pregnancies with normal glucose tolerance had their bodyweight and body composition assessed by air-displacement plethysmography. RESULTS: After controlling for neonate age at time of testing, significant differences were found between groups for percent fat (12.5 +/- 4.2% vs 13.6 +/- 4.3%; P < or = .0001), fat mass (414.1 +/- 264.2 vs 448.3 +/- 262.2 g; P < or = .05), and fat-free mass (3310.5 +/- 344.6 vs 3162.2 +/- 343.4 g; P < or = .05), with no significant differences between birth length (50.7 +/- 2.6 vs 49.6 +/- 2.6 cm; P = .08) or birthweight (3433.0 +/- 396.3 vs 3368.0 +/- 399.6 g; P = .44). CONCLUSION: Neonates born to mothers who have a normal BMI have significantly less total and relative fat and more fat-free mass than neonates born to overweight/obese mothers. Although preliminary, these data suggest that the antecedents of future disease risk (eg, cardiovascular disease, diabetes, and obesity) occur early in life.