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Yunsuk Koh,1 Heidi Bidstrup,2 David L Nichols2 1Department of Health, Human Performance, and Recreation, Baylor University, Waco, TX, USA; 2Department of Kinesiology, Texas Woman's University, Denton, TX, USA Abstract: The current study examined the effects of niacin and a single bout of aerobic exercise on plasma glucose, insulin, and C-peptide in sedentary, nondiabetic postmenopausal women. As a crossover design, 17 participants underwent four different trials: rest during the no-niacin condition (R), exercise during the no-niacin condition (E), rest during the with-niacin condition (RN), and exercise during the with-niacin condition (EN). All participants took 1,000 mg/day of extended-release niacin for 4 weeks during the with-niacin conditions (RN and EN). The exercise treatment consisted of a single bout of treadmill walking at 60% heart rate reserve until 400 kcal were expended. Blood samples were collected at 24 hours after each trial and analyzed for changes in plasma glucose, insulin, and C-peptide. A two by two analysis of variance was used to examine the changes in dependent variables, and the Bonferroni adjustment was employed as the post hoc test. The level of statistical significance was set at P

High-school girls and collegiate women have tremendous opportunities to participate in athletic teams. Young girls are also playing in club and select teams at an early age and often, year-round. There are many benefits for participating in sport and physical activity on both the physical and mental health of girls and women. Decreased risk for heart disease and diabetes mellitus, along with improved self-esteem and body-image, were among the first reported benefits of regular physical activity. In addition, sport participation and physical activity is also associated with bone health. Athletes have a greater bone mineral density compared with non-active and physically active females. The increase in bone mass should reduce the risk of fragility fractures in later life. There appears to be a window of opportunity during the development of peak bone mass in which the bone is especially responsive to weight-bearing physical activity. Impact loading sports such as gymnastics, rugby or volleyball tend to produce a better overall osteogenic response than sports without impact loading such as cycling, rowing and swimming. Relatively little is known about the impact of retiring from athletics on bone density. It appears that former athletes continue to have a higher bone density than non-athletes; however, the rate of bone loss appears to be similar in the femoral neck. The positive impact of sports participation on bone mass can be tempered by nutritional and hormonal status. It is not known whether female athletes need additional calcium compared with the general female population. Due to the increased energy expenditure of exercise and/or the pressure to obtain an optimal training bodyweight, some female athletes may develop low energy availability or an eating disorder and subsequently amenorrhoea and a loss of hone mineral density. The three inter-related clinical disorders are referred to as the 'female athlete triad'. This article presents a review of the relationship between sports training and hone health, specifically hone mineral density, in young athletic women. [ABSTRACT FROM AUTHOR]

The golf swing has been associated with mechanical injury risk factors at many joints. One swing, the Minimalist Golf Swing, was hypothesised to reduce lumbar spine, lead hip, and lead knee ranges of motion and peak net joint moments, while affecting swing performance, compared to golfers' existing swings. Existing and MGS swings of 15 golfers with handicaps ranging from +2 to -20 were compared. During MGS downswing, golfers had 18.3% less lumbar spine transverse plane ROM, 40.7 and 41.8% less lead hip sagittal and frontal plane ROM, and 39.2% less lead knee sagittal plane ROM. MGS reduced lead hip extensor, abductor, and internal rotator moments by 17.8, 19.7 and 43%, while lead knee extensor, abductor, adductor and external rotator moments were reduced by 24.1, 26.6, 37 and 68.8% respectively. With MGS, club approach was 2° shallower, path 4° more in-to-out and speed 2 m/s slower. MGS reduced certain joint ROM and moments that are linked to injury risk factors, while influencing club impact factors with varying effect. Most golf injuries are from overuse, so reduced loads per cycle with MGS may extend the healthy life of joints, and permit golfers to play injury-free for more years.

Riboflavin, a member of the B vitamin family, is a water-soluble vitamin that participates in energy metabolism processes via two coenzymes, flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), in oxidized and reduced forms. Low levels of riboflavin have been associated with growth and developmental problems. In an effort to investigate the role of hydrogen bonding in the interactions between riboflavin and chicken riboflavin binding protein, the solid state geometry characteristics of a riboflavin derivative stripped of hydroxyl groups except the primary one, N-(6'-hydroxyhexyl)isoalloxazine, were investigated and found that π-stacking and hydrogen bonding involving the isoalloxazine rings are the primary intermolecular interactions. Subsequent comparative fluorescence studies showed that at neutral pH, in presence of the protein, quenching of N-(6'-hydroxyhexyl)isoalloxazine and riboflavin occurred similarly suggesting that the hydroxyl groups were not a key component of the vitamin protein interactions in the binding pocket., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Urban adaptation to climate change is a global challenge requiring a broad response that can be informed by how urban societies in the past responded to environmental shocks. Yet, interdisciplinary efforts to leverage insights from the urban past have been stymied by disciplinary silos and entrenched misconceptions regarding the nature and diversity of premodern human settlements and institutions, especially in the case of prehispanic Mesoamerica. Long recognized as a distinct cultural region, prehispanic Mesoamerica was the setting for one of the world's original urbanization episodes despite the impediments to communication and resource extraction due to the lack of beasts of burden and wheeled transport, and the limited and relatively late use of metal implements. Our knowledge of prehispanic urbanism in Mesoamerica has been significantly enhanced over the past two decades due to significant advances in excavating, analyzing, and contextualizing archaeological materials. We now understand that Mesoamerican urbanism was as much a story about resilience and adaptation to environmental change as it was about collapse. Here we call for a dialogue among Mesoamerican urban archaeologists, sustainability scientists, and researchers interested in urban adaptation to climate change through a synthetic perspective on the organizational diversity of urbanism. Such a dialogue, seeking insights into what facilitates and hinders urban adaptation to environmental change, can be animated by shifting the long-held emphasis on failure and collapse to a more empirically grounded account of resilience and the factors that fostered adaptation and sustainability.

Background: This study investigated relations between background TV exposure (BTV) and executive function (EF) when children were engaged in activities during exposure and how cumulative risk moderated these relations., Methods: A nationally-representative survey with US caregivers (N = 1180) of 2-8-years-old children participated in a telephone survey. Data included demographic information, the child's EF, and time use across a 24-h period. Total BTV exposure within various contexts was calculated from diaries., Results: In the direct effects regressions, BTV during sleep predicted poorer EF for all children. Playing by self with BTV predicted poorer EF for preschoolers while playing with others with BTV predicted stronger EF for school-age children. When cumulative risk was included, engaging in routines and chores with BTV predicted stronger EF for preschoolers while high-risk school-age children evidenced stronger EF when exposed to BTV while socializing with family or engaging in academic enrichment. Low-risk school-age children evidenced poorer EF in both contexts., Conclusions: Reducing exposure can mitigate negative relations. This is an important goal as children are exposed to more of all forms of screen media during the COVID-19 pandemic. Results confirm the American Academy of Pediatrics' recommendation that TV be turned off in the background when a child is in the room., Impact: Young children are exposed to significant hours of background television per day across multiple contexts: socializing with family, playing alone or with others, engaging in routines/chores, eating/drinking, and sleeping. Most exposure (46%) occurred while sleeping. Sleep exposure predicted poorer executive functioning (EF). During background TV exposure, as preschoolers' time spent playing alone increased, EF scores worsened. School-age children's time spent playing with others during exposure predicted stronger EF. EF scores for low-risk school-age children worsened when background TV was on while socializing with family or engaging in academic activities whereas the reverse was true for high-risk school-age children., (© 2022. The Author(s), under exclusive licence to the International Pediatric Research Foundation, Inc.)

Background: High-intensity functional training is a popular form of exercise, but little is known about how it compares to more traditional exercise patterns., Methods: Thirty healthy, physically active adults (15 males, 15 females) performed a high-intensity functional training workout (HIFT) and a traditional workout (TRAD). Cardiorespiratory responses were measured during and for 15 min after each workout., Results: Peak heart rate (males: 187±7 vs. 171±10 bpm, P<0.001; females: 191±9 vs. 175±6 bpm, P<0.001), peak VO2 (males: 3.80±0.58 vs. 3.26±0.60 L/min, P<0.001; females: 2.65±0.26 vs. 2.36±0.21, P<0.001), and average 15 min recovery VO2 (males: 1.15±0.20 vs. 0.99±0.17 L/min, P<0.001; females: 0.77±0.10 vs. 0.71±0.07 L/min, P=0.019) were significantly higher in HIFT vs. TRAD. Aerobic energy expenditure was significantly higher in HIFT compared to TRAD in males (9.01±1.43 vs. 8.53±1.38 kcal/min, P=0.002) but was not significantly different between the two workouts in females (6.04±0.53 vs. 5.97±0.50 kcal/min, P=0.395). Postexercise systolic blood pressure (SBP) was significantly higher than pre-exercise SBP following both HIFT (males: 124±13 mmHg pre to 154±28 mmHg post, P<0.001; females: 110±7 mmHg pre to 140±15 mmHg post, P<0.001) and TRAD (males: 124±13 mmHg pre to 142±16 mmHg post, P=0.002; females: 112±8 mmHg pre to 123±10 mmHg post, P=0.002), however, HIFT led to a greater increase compared to TRAD in females (P=0.001). Postexercise diastolic blood pressure (DBP) was significantly lower than pre-exercise DBP following both HIFT (males: 77±9 mmHg pre to 64±6 mmHg post, P<0.001; females: 71±8 mmHg pre to 64±7 mmHg post, P=0.011) and TRAD (males: 82±7 mmHg pre to 72±7 mmHg post, P<0.001; females: 73±8 mmHg pre to 65±8 mmHg post, P<0.001). Mean arterial blood pressure was unchanged following both workouts., Conclusions: High-intensity functional training may be an effective form of exercise for caloric expenditure and may elicit greater cardiorespiratory stress than traditional exercise.

Background: Media use is pervasive among young children. Over 95% of homes in the US have one or more televisions, and access to screen-based media continues to grow with the availability of new technologies. Broadly, exposure to large amounts of screen-based media is negatively related to language and literacy skills; however, questions remain as to the features of media that are detrimental to these skills and the mechanisms by which they are connected., Methods: A nationally representative sample of 922 children aged 3-7 years was recruited. Parents completed phone-based questionnaires of children's language, literacy, and self-regulation skills and a 24-h time diary in 2009. Path models were used to estimate the direct and indirect associations between context and content of media use with language and literacy skills., Results: Background and entertainment television, but not educational television, were negatively associated with language and literacy. Further, the link between background television and language and literacy skills was fully mediated by self-regulation., Conclusions: Television left on in the background and entertainment programming (or that which is not child-directed) is particularly detrimental for language and literacy skills. Additional research is needed to further explore self-regulation as a mechanism by which screen use predicts academic skills., Impact: Background and entertainment television are negatively associated with language and literacy skills in 3- to 7-year-old children. We find no relation between educational programming and language and literacy skills. Self-regulation is a potential mechanism underlying the relation between background television and language and literacy skills. Anticipatory guidance for parents would be to consider turning off screen-based media devices when no one is watching. Parents should be mindful of the types of content their children are watching on screen-based media.

Objective: The aim of this study was to identify the effects of menopausal and body composition statuses on measures of total and regional body composition and dyslipidemia in women. Methods: Sedentary, non-smoking women (N = 212), not currently treated for dyslipidemia were grouped based on 2 categories: (1) menstrual status: premenopausal or postmenopausal and (2) body composition status: normal weight (NW; BMI < 25 kg/m² and body fat (BF) < 36%), normal weight obese (NWO; BMI < 25 kg/m² and BF > 36%), or obese (BMI > 25 kg/m² and BF > 36%), to determine differences in total and regional body composition and measures of lipid and lipoprotein-cholesterol concentrations. Results: Overall, a greater prevalence of NWO was observed in postmenopausal versus premenopausal women. Being postmenopausal was associated with higher TC, LDL-C, non-HDL-C, HDL-C, and HDL₃-C. Premenopausal NWO women had elevated LDL-C and VLDL-C comparable to obese women. Postmenopausal NWO women had elevated Tg and VLDL-C and lower HDL-C similar to obese women. Conclusions: Menopausal status was not associated with differences in fat distribution, however, the age-related differences in lipids and lipoproteins appear to be due to a difference in menopausal status exacerbated in women who are NWO.

There is a lack of current research to support the efficacy of a combination of equine-assisted activities (EAA) and brain building activities to influence motor skill competencies in youth with neurodevelopmental disorders (ND). The primary objective of this study was to quantify changes in motor skill proficiency before and after 8 weeks of EAA and brain-building activities in youth with ND. A secondary objective was to quantify changes in motor skill proficiency before and after 1 year of EAA and brain-building activities in youth with ND. Twenty-five youth completed the same 32-week protocol that was separated into 4, 8-week blocks, in the following order: (1) control; (2) EAA-only; (3) washout; (4) GaitWay block (EAA and brain building activities). Before and after each block, motor skills were assessed using the Short Form of the Bruininks-Oseretsky Test of Motor Proficiency-Version 2 (BOT-2). Seven youth continued with the GaitWay intervention for one additional year, and the BOT-2 Short Form was also administered following this intervention. A repeated-measures analysis-of-variance was performed to compare BOT-2 subtest and overall scores between interventions with a significance of 0.05. Manual dexterity was higher at Post-Washout [3.3 (2.4)] vs. Pre-Control [2.2 (2.1); p = 0.018] and Post-Control [2.6 (2.0); p = 0.024], and at Post-GaitWay vs. Pre-Control [3.2 (2.4) vs. 2.2 (2.1); p = 0.037]. Upper-limb coordination was higher at Post-GaitWay vs. Post-Control [6.0 (4.1) vs. 3.9 (3.8); p = 0.050]. When compared to Pre-Control [3.2 (3.0)], strength was higher at Post-EAA [4.9 (3.5); p = 0.028] and at Post-GaitWay [5.2 (2.9); p = 0.015]. Overall scores were higher at Post-GaitWay [39.1 (22.2)] when compared to Pre-Control [32.4 (21.6); p = 0.003] and Post-Control [32.5 (21.9); p = 0.009]. Additionally, motor skills were maintained for 1 year following the Post-GaitWay testing session among seven participants. This is the first known study to include and demonstrate the short-term and long-term effects of a combination of EAA and brain building activities with motor proficiency in youth with ND. Clinical Trial Registration: Motor Skill Proficiency After Equine-Assisted Activities and Brain-building Tasks; www.ClinicalTrials.gov, identifier: NCT04158960., (Copyright © 2020 Rigby, Davis, Bittner, Harwell, Leek, Johnson and Nichols.)

The purpose of this study was to characterize high-intensity functional training (HIFT) in physically inactive adults. Four men and 10 women who were inexperienced with HIFT and not performing regular physical activity performed HIFT 3 days/week for 8 weeks. Health and fitness measures were assessed before and after the intervention. Resting heart rate (73 ± 12 vs. 68 ± 11 bpm) and resting diastolic blood pressure (71 ± 7 vs. 65 ± 6 mmHg) were reduced, while resting systolic blood pressure remained unchanged. Absolute VO 2max (2.53 ± 0.68 vs. 2.69 ± 0.66 L/min) and relative VO 2max (32.51 ± 8.84 vs. 34.31 ± 8.63 mL/kg/min) were improved. Lean body mass (48.20 ± 13.37 vs. 49.26 ± 13.81 kg) was increased, but fat mass was unchanged. Performance on the leg press (164.61 ± 54.35 vs. 201.62 ± 67.50 kg), bench press (39.12 ± 20.15 vs. 46.43 ± 21.18 kg), YMCA bench press (26 ± 13 vs. 37 ± 16 reps), one-minute sit-up (25 ± 9 vs. 32 ± 10 reps), and sit-and-reach (30.36 ± 11.36 vs. 32.14 ± 9.66 cm) were all increased. High-intensity functional training may be useful for improving health-related physical fitness parameters in physically inactive adults.

The purpose of this study was to compare acute cardiometabolic responses to 3 modes of treadmill exercise in adults diagnosed with Parkinson's disease (PD). Eight elderly adults with PD (67.9 ± 3.0 yr) completed 1 session each on a land, aquatic, and antigravity treadmill at 50% body weight. Participants walked from 1 to 3 mph in 0.5-mph increments at 0% grade for 5 min at each speed. Heart rate, energy expenditure, blood pressure, and rating of perceived exertion were measured at rest and during exercise. All variables except diastolic blood pressure increased with speed on all treadmills (p < .001). At all speeds except 1.5 mph, heart rate was higher on the land treadmill than the antigravity treadmill (p < .05). Exercising on an aquatic or antigravity treadmill elicits similar submaximal physiologic responses to exercise on a land treadmill in adults with PD.

Background: The purpose of this study was to compare the effect of aquatic treadmill exercise (ATM) to land treadmill exercise (LTM) in adults with and without type 2 diabetes (T2D)., Methods: Five participants with T2D (4 females, 1 male; age=51±3 years; height=170±3 cm; weight=96±11 kg; body fat=32±1%) and five participants without T2D (4 females, 1 male; age=51±3 years; height=170±3 cm; weight=71±15 kg; body fat=27±2%) completed the study. Participants completed three, 5-minute stages of exercise at 3.2 km/h, 4.8 km/h and 6.4 km/h with 0% grade on land and aquatic treadmills. Heart rate (HR), systolic and diastolic blood pressure (SBP and DBP), absolute and relative oxygen consumption (VO2), and energy expenditure were measured at rest and during steady-state exercise at each intensity. A 2x2x4 Mixed Factorial ANOVA and Bonferroni post-hoc test with a significance level of 0.05 was used., Results: All variables increased as speed increased (P<0.05) independent of group or mode. The HR value was higher on the LTM versus the ATM independent of group and treadmill stage (P=0.002) and SBP was higher in the T2D group versus no T2D independent of treadmill mode and stage (P=0.01). Relative VO2 was higher in the group without T2D compared to the T2D group at 6.4 km/h independent of treadmill mode (P=0.032)., Conclusions: Although there is some evidence for the varying effects of aquatic and land exercise when comparing those with and without T2D, cardiorespiratory and metabolic variables are similar in both groups during locomotion on land and in an aquatic environment.

Purpose: This study explored the effect of whole-body vibration (WBV) using accelerations of 2.56 g to 7.68 g on lower-body detraining., Methods: All participants (N = 20) were trained using a lower-body resistance-training program for 30 min twice per week from Week 0 to Week 6. At the end of the program, they were randomly assigned to a control group that performed no further training or a WBV group that performed a progressive static WBV program. Data for the 5-repetition-maximum (5RM) squat and extensors and flexors of the knee and ankle were collected at Weeks 0, 6, 8, 10, and 12 for all participants., Results: Two-way (condition vs. time) analysis of variance revealed that although the WBV group maintained strength in the 5RM from Week 6 through Week 8 and the control group had a lower 5RM in Week 8 from Week 6, no differences in the 5RM squat existed between the groups at Week 8. Two-way factorial multivariate analysis of variance revealed no differences between the groups at any of the time for torque of knee flexion, dorsiflexion, or plantar flexion., Conclusion: Static WBV of 2.56 g to 7.68 g did not attenuate detraining of the flexors and extensors of the knee and ankle.

Deficits in social behavior and communication skills are correlated with reduced gross motor skills in children with autism spectrum disorders (ASD). The ExerciseBuddy application (EB app) was designed to communicate these motor skills to those with ASD and integrates evidence-based practices such as visual support and video modeling supported by The National Professional Development Center on Autism Spectrum Disorders. The purpose of this study was to determine the effectiveness of the EB app in facilitating increased physiologic responses to physical activity via a continuous measurement of energy expenditure and heart rate versus practice-style teaching methods in children with ASD. Six children, ages 5 to 10years, diagnosed with ASD were recruited. Each participant performed a variety of locomotor or object control skills as defined by the Test of Gross Motor Development-2 once per week for 4weeks. Motor skills were communicated and demonstrated using either practice-style teaching methods or the instructional section of the EB app. Energy expenditure and heart rate were measured continuously during each 12-minute session. A Wilcoxon signed-rank test was performed to assess any differences between the use of the app and practice-style teaching methods. The use of the EB app elicited greater values for peak energy expenditure (p=0.043) and peak heart rate response (p=0.028) while performing locomotor skills but no differences were observed while performing object control skills. Similarities were observed with average physiologic responses between the use of the EB app and practice-style teaching methods. The use of the EB app may allow for a greater peak physiologic response during more dynamic movements and a similar average cardiovascular and metabolic response when compared to practice-style teaching methods in children with ASD., (Published by Elsevier Inc.)

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%VO 2max . 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 AUC I ). 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 AUC I 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 AUC I 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.

Unlabelled: The relationship between spinal curvature and bone mineral density (BMD) in women was examined. Significant relationships were observed between spinal curvature and BMD in both pre- and postmenopausal women. Excessive spinal curvature may be associated with low bone mass in premenopausal women., Introduction: The purpose of this study was to examine the associations between spinal measurements of thoracic and lumbar curvatures and bone mineral density in pre- and postmenopausal women., Methods: The data for this study were obtained from the Texas Woman's University Pioneer Project. Female participants (n = 242; premenopausal n = 104, postmenopausal n = 138) between the ages of 18 and 60 years were evaluated on multiple health measures. Thoracic and lumbar curvatures were measured with a 24-in. (60 cm) flexicurve. Bone mineral density was assessed via dual-energy X-ray absorptiometry (Lunar DPX IQ, version 4.6e). Pearson correlations and logistic regression analysis were used to examine the associations between the obtained spinal curvature measurements and bone mineral density. Significance was set at p < .05., Results: Significant correlations were observed for the femoral neck and lumbar spine bone mineral density with thoracic and lumbar curve in premenopausal women (r = -.344 to - .525; p < .001). Slightly weaker, but significant, correlations were observed for femoral neck and lumbar spine in relation to thoracic and lumbar curve in postmenopausal women (r = -.288 to -.397; p < .01). Premenopausal women with thoracic curvature greater than 4 cm had a greater risk of having low bone mass compared to premenopausal women with less than 4 cm of curvature (odds ratio = 3.982, 95 % CI = 1.206, 13.144)., Conclusions: The observed negative relationship suggests that as either thoracic or lumbar curvature increases, the regional bone mineral density decreases in both pre- and postmenopausal women.

The purpose of the study was to determine the efficacy of a low-volume, moderate-intensity bout of resistance exercise (RE) on glucose, insulin, and C-peptide responses during an oral glucose tolerance test (OGTT) in untrained women compared with a bout of high-volume RE of the same intensity. Ten women (age 30.1 ± 9.0 years) were assessed for body composition, maximal oxygen uptake, and 1-repetition maximum (1RM) before completing 3 treatments administered in random order: 1 set of 10 REs (RE1), 3 sets of 10 REs (RE3), and no exercise (C). Twenty-four hours after completing each treatment, an OGTT was performed after an overnight fast. Glucose area under the curve response to an OGTT was reduced after both RE1 (900 ± 113 mmol·L(-1)·min(-1), p = 0.056) and RE3 (827.9 ± 116.3, p = 0.01) compared with C (960.8 ± 152.7 mmol·L(-1)·min(-1)). Additionally, fasting glucose was significantly reduced after RE3 (4.48 ± 0.45 vs. 4.90 ± 0.44 mmol·L(-1), p = 0.01). Insulin sensitivity (IS), as determined from the Cederholm IS index, was improved after RE1 (10.8%) and after RE3 (26.1%). The reductions in insulin and C-peptide areas after RE1 and RE3 were not significantly different from those in the C treatment. In conclusion, greater benefits in glucose regulation appear to occur after higher volumes of RE. However, observed reductions in glucose, insulin, C-peptide areas after RE1 suggest that individuals who may not well tolerate high-volume RE protocols may still benefit from low-volume RE at moderate intensity (65% 1RM).

Niacin and exercise positively alter blood lipids and lipoproteins via different mechanisms. However, the effects of niacin combined with exercise on blood lipid and lipoprotein profiles have not been investigated in sedentary postmenopausal women. The current study examined the responses of blood lipids and lipoproteins to niacin and exercise in 18 sedentary postmenopausal women, who underwent four conditions: no-niacin rest, no-niacin exercise, niacin rest, and niacin exercise. Participants ingested 1,000 mg/day of extended-release niacin for 4 weeks during the niacin condition. As an exercise treatment, participants performed a single bout of exercise on a treadmill at 60% heart rate reserve until 400 kcal were expended. Extended-release niacin without the exercise intervention significantly (p < .001) increased high-density lipoprotein cholesterol and high-density lipoprotein-2 cholesterol by 12.4% and 33.3%, respectively, and decreased the total cholesterol to high-density lipoprotein cholesterol ratio by 14.8%. Thus, 4 weeks of 1,000 mg/day of extended-release niacin can improve the blood lipid and lipoprotein profiles in sedentary postmenopausal women.

The purpose of this study was to investigate the influence of jumping activities and nutrition education on bone accretion in prepubescents. Fourth-grade children were divided into four groups: jumping (n = 61), nutrition (n = 9), jumping plus nutrition (n = 14), and control (n = 28). Interventions spanned the fourth and fifth grade academic years. Assessments were gathered at 0, 8 and 20 months. Baseline BMD values were (mean +/- SD): lumbar (0.752 +/- 0.095 g/cm2), neck (0.794 +/- 0.089 g/cm2) and total (0.907 +/- 0.060 g/cm2). There was a significant increase in BMD over time. However, the interventions produced no significant effects. Twice weekly jumping and/or biweekly nutrition education did not influence bone accrual.

Objective: To determine the impact of written intervention materials on child feeding practices of mothers and on physical activity behaviors of preschoolers., Design: Mothers were divided into 3 groups: newsletter (n = 30), booklet (n = 31), and control (n = 31). Questionnaires were completed before and after a 12-week intervention., Setting: Mail correspondence., Participants: White (90%), full-time mothers (76%) in their thirties (68%)., Interventions: Nutrition and activity information was provided as twelve 4-page weekly newsletters or one 52-page booklet., Main Outcome Measures: Child feeding factors, physical activity practices., Analysis: Child feeding factors were analyzed using Kruskal-Wallis and Wilcoxon. Physical activity practices were analyzed using 2-way chi-square and sign tests. The significance level was set at .0125., Results: There was a significant decrease in the "pressure to eat" score for participants in the newsletter group (2.5 +/- 1.0 to 2.1 +/- 1.0, P < .01). No other differences in feeding practices were observed. At baseline, 43% of the mothers said their child spent at least 1 hour per day in active play, and 63% said their child watched television less than 2 hours per day. A significant increase in outdoor play was reported in the newsletter (P < .01) and control (P < .01) groups., Conclusions and Implications: This study is one of the first to indicate that child feeding practices may be modifiable.

Undesirable changes in health-related parameters are thought to occur in retiring female athletes, but this has not been examined in longitudinal studies. The purpose of this study was to examine longitudinal changes in bone mineral density (BMD), body composition, and dietary intake in gymnasts and controls. Nonathletic, college-age women (: n = 9) were selected as a control group for comparison to the gymnasts (n = 10). Initial BMDs for the gymnasts were determined by using dual energy X-ray absorptiometry (Lunar, DPX) at the beginning of their final competitive year. Initial BMDs for the controls were measured during a similar time-frame. Follow-up measurements were made at least 1-year after the initial measurement. Gymnasts had significantly greater BMD of the femoral neck (1.262 versus 1.058 g/cm2, respectively), Ward's triangle (1.230 versus 1.008 g/cm2), greater trochanter (1002 versus 0.822 g/cm2), and total body (1.232 versus 1.145 g/cm2) than controls while still competing (P < .05). Following retirement from competition, (mean years of retirement, 4 years), BMD of the gymnasts remained significantly greater than controls at total body, femoral neck, trochanter, and Ward's triangle (P < .05). Significant declines in femoral neck, Ward's triangle, and greater trochanter BMD were found in both gymnasts and controls (0.72% to 1.9% per year), but only gymnasts had a significant decline at the lumbar spine (0.87% per year). In conclusion, BMD changes in former gymnasts appear to be site-specific, and gymnasts continue to have greater proximal femur BMD than controls, despite their decreased exercise, which may help postpone or prevent osteoporosis later in life.

Sixty-one nonsmoking, healthy, young, menstruating women aged 18 to 30 years generally considered at peak skeletal bone mass were screened for diseases and drugs known to adversely affect bone mineral density (BMD). Anthropometric measures, BMD of the lumbar spine (LS) and femoral neck (FN), exercise time, selected nutrient, and energy intake were compared. The women were categorized by frame size and body mass index (BMI), with the upper range for normal weight (NW) being BMI 23.0 to 25.9 (n=30) and lower weight (LW) being BMI 16.0-19.9 (n=31). Multivariate t tests, Pearson correlations, and independent sample t tests were used for statistical analysis. Ten of 21 in the LW group, all with small frames, had varying degrees of low BMD of the LS and/or FN. The amount of exercise time was greater in the NW group. Energy and nutrient intakes did not differ significantly between groups.

Objective: To examine the effects of 15 months of resistance training on bone mineral density (BMD) in female adolescents (aged 14 to 17 years)., Study Design: Participants were randomly assigned to either a training (n = 46) or control group (n = 21). BMD and body composition were measured by using dual-energy x-ray absorptiometry. Strength was assessed by means of one-repetition maximums for the leg press and bench press. The exercise group trained 30 to 45 minutes a day, 3 days per week, using 15 different resistance exercises. Control participants remained sedentary (<2 hours of exercise per week)., Results: Leg strength increased significantly (40%) in the exercise group, but there were no changes in the control group. Femoral neck BMD increased significantly in the training group (1.035 to 1.073 g/cm(2), P <.01) but not in the control group (1.034 to 1.048 g/cm(2)). No significant changes were seen in either group in lumbar spine BMD (1.113 to 1.142 g/cm(2) and 1.158 to 1.190 g/cm(2), respectively) or total body BMD (1.103 to 1.134 g/cm(2) and 1.111 to 1.129 g/cm(2), respectively)., Conclusion: Resistance training is a potential method for increasing bone density in adolescents, although such a program would be best done as part of the school curriculum.

Good bone health is important to everyone, regardless of age. Osteoporosis is a preventable disease, and steps for increasing bone mass should begin at an early age. To increase bone mass, much of the recent evidence suggests that the best time for intervention with calcium or exercise may be during the prepubertal years. In the older female athlete, BMD is typically well above normal, but even young amenorrheic athletes can have bone density values equal to that of an elderly osteoporotic woman. Myriad treatment options are available for the person with low bone mass, but prevention is a much more preferable alternative.

Individuals diagnosed with Crohn's disease are at an increased risk for developing low bone density. The exact cause of low bone mineral density in Crohn's disease patients has not been determined. The purpose of this study was to assess the incidence of low bone mineral density in premenopausal women with Crohn's disease and to determine the role diet plays in bone mineral density for this population. Bone mineral density of the lumbar spine (L2-L4), proximal femur, and forearm was measured in 51 female controls and 50 females with Crohn's disease using dual energy X-ray absorptiometry (Lunar DPXPlus, Madison, WI). Dietary intake for all Crohn's disease participants was analyzed using both 3-d dietary records and a food frequency questionnaire. When compared to healthy controls, bone mineral density values of Crohn's disease participants were decreased for all sites, particularly the spine (1.169 +/- 0.114, p = 0.054), Ward's area (0.831 +/- 0.128, p = 0.052), and the femoral neck (0.927 +/- 0.100, p = 0.01). Factors associated with lower bone density in Crohn's participants were weight, corticosteroid usage, length and age of diagnosis, history and length of resection, and dietary intakes of magnesium, copper, magnesium, vitamin K, and zinc. The results of this study indicate for the first time that diet plays a role in the development of low bone density in premenopausal women with Crohn's disease.

The purpose of this study was to determine if differences exist in premenopausal women between z-scores for lumbar spine and proximal femoral bone mineral densities (BMD). Participants were 237 women ranging in age from 20 to 45 years. BMDs of the lumbar spine and proximal femur (femoral neck, Ward's area, and trochanter) were assessed using dual-energy X-ray absorptiometry (Lunar DPX). Mean (+/-SD) age, height, and weight of the participants were 29.4 +/- 6.9 years, 164.4 +/- 6.1 cm, and 64.9 +/- 12.1 kg, respectively. Lumbar spine BMD and BMD at the femoral neck, Ward's area, and trochanter were significantly correlated with large SEEs (r = 0.59-0. 65; SEE = 0.09-0.11). No positive correlation with age and BMD at any site was seen in this population but a significant negative correlation with age was seen in the proximal femur beginning at age 30. Twenty to 24% of the 20-29-year-olds exhibited a difference in z-scores of greater than 1 between the spine and sites in the proximal femur. This percentage increased to 32-46% in the 30-45-year-olds but the nature of the observed differences changed. The differences in spine and proximal femoral z-scores that are seen in the older age group appear to be the result of the earlier onset of bone loss in the proximal femur rather than an initial difference in peak bone mass which has been maintained.

The purpose of this study was to relate several variables (age, sex, race, number of extractions performed, dental arch, tooth position, mobility, root length, osseous resorptive defects, soft tissue inflammation, and history of preexisting pain) to the prevalence of parental report of pain in their children between forty-eight hours before (preexisting pain) and seven hours after extraction of their primary teeth (postextraction pain). Sixty-two children, ages two to ten years, were studied. The results indicated that there was no relationship between preexisting pain and the report of postextraction pain. There was a trend for females, primary molars, and presence of osseous resorptive defects to be associated with preexisting dental pain Root length (complete root formation) and presence of adjacent soft tissue inflammation were statistically significant for preexisting pain. Chronologic age was the only variable studied that was associated with postextraction pain in these children. Although the existence of pain is difficult to assess in children, the results of this study may be useful in a clinician's decision-making process as to the need for prescribed analgesics following extraction of primary teeth.

The purpose of this study was to determine if differences existed between right and left proximal femur bone mineral density (BMD) in a group of women. Participants for the study were 198 women ranging in age from 16 to 73 years. Bone mineral densities of both proximal femurs (femoral neck, Ward's area, and trochanter) were assessed using dual energy X-ray absorptiometry (Lunar DPX). Mean (+/-SD) age, height, and weight of the participants were 32.9 +/- 18 years, 164 +/- 7.4 cm, and 64.9 +/- 12.1 kg, respectively. Significant differences between right and left femoral BMDs were found only in the trochanter. Overall, mean differences in BMD were low (neck = 0. 7%, Ward's = 0.2%, and trochanter = 1.9%) but individual variations were as high as 22%. Based on BMD z-scores of <-1.0, 84 women were classified as "at risk" for osteoporosis. When right and left z-scores were compared, misclassifications of at risk women were 4, 15, and 11 for neck, Ward's area, and trochanter, respectively. In conclusion, analyses of both right and left proximal femurs may not be necessary for either the researcher or the clinician.

The associations of body fat distribution, sex hormone levels, and bone mineral density (BMD) were examined in 52 postmenopausal Caucasian women. Body fat distribution was assessed by waist to hip ratio (WHR) and abdominal fat weight (between the iliac crest and L1), as determined by dual energy x-ray absorptiometry. Bone mineral densities were determined by dual energy x-ray absorptiometry, and total estradiol, total testosterone, and sex hormone-binding globulin (SHBG) levels were determined by RIA. Subjects taking hormone replacement had significantly greater total estradiol and SHBG concentrations and a lower free androgen index. BMDs tended to be higher in subjects taking estrogen replacement after adjustment for body weight. There was no difference between subjects taking hormone replacement or not taking hormone replacement in WHR or abdominal fat weight. Subjects with a gynoid (lower body) distribution of body fat had higher SHBG concentrations than subjects with a more android (upper body) distribution of body fat. Subjects with an android distribution of body fat had greater BMDs than subjects with a gynoid distribution of body fat. Abdominal fat weight and WHR were significant predictors in regression models for all BMD parameters. The results of this study suggest that there is an association between body fat distribution and BMD, with the android distribution having higher BMDs.

Previous investigations demonstrated that administering a preoperative analgesic can reduce postextraction pain in adults. Studies also have shown that ibuprofen was superior in alleviating postextraction pain when compared with acetaminophen. The purpose of this study was to compare the efficacy of the preoperative administration of ibuprofen, acetaminophen, and placebo in reducing postextraction pain in children. Sixty children, aged 2-10 years, requiring primary teeth extractions, were selected to participate in the study. Patients were assigned in a blind, random fashion to one of the three pretreatment drug groups. Parental report of their child's pain and use of analgesics during the immediate 7-hr postoperative period was elicited by telephone the day after the extraction procedure. Thirty-five percent of the patients were reported by their parents to experience postextraction pain. Of those patients, 52% received postoperative analgesics for pain relief (18% of the total). Although there was a trend toward reduced postextraction pain reported by the parents, the preoperative administration of neither analgesic was found to be statistically superior by chi-square analysis to placebo administration.

The purpose of this study was to examine the effect of 27 wk of gymnastics training on bone mineral density (BMD), body composition, insulin-like growth factor I (IGF-I), and osteocalcin. Subjects were 11 female intercollegiate gymnasts and 11 controls. Dual energy x-ray absorptiometry (Lunar DPX) was used to determine BMD (L2-L4 and femur) and to assess body composition. The gymnasts were significantly lower in weight (53.9 and 60.8 kg) and % body fat (22.6 and 30.6) compared with controls. After training, body weights of gymnasts remained the same but there was a significant increase in lean tissue mass of 2.9 kg (6.7%, P < 0.05). No changes in body composition were observed in the controls. The gymnasts had significantly higher mean lumbar (1.321 vs 1.225), and femoral neck (1.163 vs 1.079) BMD (g.cm-2) than the controls. Lumbar BMD increased significantly (1.3%) in gymnasts following training but femoral neck BMD did not increase. No BMD changes occurred in the control group. Regarding serum IGF-I, no differences were seen between the groups or across time. Serum osteocalcin values were significantly higher in the gymnasts than the controls, but no differences were found across time. In conclusion, gymnasts had significantly higher BMDs than controls, and a significant increase in lumbar BMD was seen in the gymnasts following 27 wk of training.

The kinetics of glucose repression of cytochrome c synthesis was measured by a radioimmune assay. When 5 or 10% glucose was added to a derepressed culture, the rate of cytochrome c synthesis was reduced to the repressed level with a half-life of 2 min. The addition of 1 or 0.5% glucose repressed the rate of cytochrome c synthesis to the same level as high glucose concentrations but with a longer half-life of 3 min. Glucose repression had no effect on the stability or function of the cytochrome c protein. Cellular levels of active cytochrome c mRNA during glucose repression were measured by translation of total cellular polyadenylic acid-containing RNA and immunoprecipitation cytochrome c from the translation products. The results of these measurements indicate that glucose represses the rate of cytochrome c synthesis through a reduction in the level of translatable cytochrome c mRNA.

DNA from the cloned yeast iso-1-cytochrome c, cycl, gene was used in a hybridization assay to measure levels and rates of synthesis of cycl RNA. Derepressed cells synthesized cycl RNA at 6 times the rate of that of glucose-repressed cells. Upon glucose addition to a derepressed culture, the transcription of the cycl gene was repressed within 2.5 min. The half-life of hybridizable cycl RNA was determined to be 12-13.5 min under repressed and derepressed conditions and during repression. The results demonstrate that the expression of the cycl gene is subject to transcriptional regulation.

The effects of the mitochondrial protein synthesis inhibitor chloramphenicol and the mitochondrial F0 adenosine triphosphatase inhibitor oligomycin on the synthesis of nucleus-encoded cytochrome c protein were studied. Both inhibitors stimulated cytochrome c protein synthesis in the derepressed state (growth in media containing 2% raffinose) but had no effect on the synthesis of the cytochrome c protein in the repressed state (growth in media containing 5% glucose). Oligomycin uncoupled the synthesis of the apoprotein from its processing into the hemoprotein. Neither antibiotic had a significant effect on the rate of glucose repression of cytochrome protein synthesis. The kinetics of cytochrome c derepression and the effects of these two antibiotics on these kinetics were also studied. Cells were derepressed by transfer from glucose- to faffinose-containing media, and the rate of cytochrome c synthesis increased from the repressed to the derepressed level during the second hour of derepression. Chloramphenicol delayed this derepression, but after 5 h the rate of cytochrome c protein synthesis increased to twice the rate of synthesis in uninhibited cells. On the other hand, oligomycin inhibited derepression of cytochrome c. These results are discussed with respect to the effects of mitochondrial function in the derepressed and repressed states and during the processes of repression and derepression of cytochrome c.