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Background: The dramatic increase in pediatric obesity has renewed interest in accurate methods and screening indexes for identifying at-risk children and youth. Whether age-specific standards are needed is a factor that remains uncertain. Purpose: This study was designed to describe the age-specific fatness-risk factor relationship in boys and girls across a wide age range. Methods: Data were from 12,279 white, black, and Mexican-American children and adolescents from the National Health and Nutritional Examination Surveys (NHANES) III (1998 -1994) and IV (1999 -2004). Children were grouped based on percent fat, estimated from subscapular and triceps skinfolds, and the age-specific relationships between percent fat and chronic disease risk factors (e.g., blood pressure, lipids and lipoprotein levels, glucose, insulin, and circulating C-reactive protein levels) were described in boys and girls, aged 6 -18 years. Results: Percent fat was significantly related to risk factor levels. At higher levels of percent fat, the prevalence of adverse cardiovascular disease risk factors was higher, particularly above 20% fat in boys and above 30% fat in girls. In boys and girls, the interaction term age by percent fat was a significant predictor of risk factors, whereas the percent fat by race interaction term was nonsignificant. Conclusions: The results demonstrate a strong relationship between chronic disease risk factors and percent fat in children and youth that varies by age in boys and girls. (Am J Prev Med 2011;41(4S2):S77-S86) © 2011 American Journal of Preventive Medicine

This study examined whether differences in waist circumference (WC) and pedometer placement (anterior vs. midaxillary vs. posterior) affect the agreement between pedometer and observed steps during treadmill and self-paced walking. Participants included 19 pairs of youth (9- 15-years-old) who were matched for sex, race, and height and stratified by WC (high WC: HWC; low WC: LWC). Participants performed 3-min treadmill-walking trials at speeds of 59, 72, and 86 m x min(-1) and a 400-m self-paced walking trial on level ground. Bland-Altman plots were used to assess the agreement between pedometer and observed steps of spring-levered pedometers by WC, pedometer placement, and walking speed. In the HWC group, the posterior pedometer placement consistently agreed most closely with observed steps at all treadmill speeds and during self-paced walking. In the LWC group, no single pedometer placement consistently agreed most closely with observed steps at all treadmill speeds and during self-paced walking. We conclude that a posterior pedometer placement improves step-count accuracy in most youth with an HWC at a range of walking speeds on level ground.

The purpose of the study is to determine whether cardiovascular disease risk factor differences exist between Active Special Olympians, Inactive Non-Special Olympians, and Active Non-Special Olympians. Resting blood pressure, total and abdominal body fat, fasting cholesterol profiles, and fasting insulin were measured in 145 (72 women, 73 men) adults with mild mental retardation. Active Special Olympians (n = 45) possessed lower diastolic blood pressures, body fat percentages, abdominal fat, triglycerides, and insulin than Inactive Non-Special Olympians (n = 38) and possessed lower body fat percentages than Active Non-Special Olympians (n = 62). Active Non-Special Olympians possessed lower triglycerides and insulin than Inactive Non-Special Olympians. Future prospective trials are needed to determine whether Special Olympics participation may be one effective component of community-based physical activity programs aimed at reducing cardiovascular disease risk.

The objective was to determine whether higher physical activity is associated with lower serum C-reactive protein (CRP), independent of oral hormone replacement therapy (HRT) status and body fatness, in 133 postmenopausal women using a cross-sectional exploratory design at a university research laboratory. The subjects were 133 postmenopausal women, age 50-73 years, with no evidence of coronary artery disease or diabetes. The main outcome measures were: serum CRP, physical activity as measured by Stanford 7-day activity recall, body fat (both total and regional) as measured by dual energy X-ray absorptiometry (DXA), and anthropometry (waist and hip circumference). Secondary outcome measures included fasting plasma glucose and insulin as well as fasting serum triglycerides, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol. Higher physical activity energy expenditures were significantly associated with lower serum CRP levels (r = -0.18, P = 0.041), independent of oral HRT use, age, smoking behavior, alcohol consumption, aspirin use, and statin use. However, in the complete multivariate model, which included body fat, older ages (P = 0.047), greater trunk fat masses (P < 0.001), any oral HRT use (P < 0.001), and unopposed oral estrogen use (P = 0.012) were the sole independent predictors of higher serum CRP levels. The complete multivariate model accounted for 58% of the variance in serum CRP. We conclude that the association between higher physical activity and lower serum CRP levels is dependent on the lower body fat of the more active women, yet independent of oral HRT use. Future intervention trials should determine whether diet- and exercise-related reductions in body fat may be effective ways to diminish the proinflammatory effects of oral HRT in postmenopausal women.

Little information has been reported on the leisure time physical activity (LTPA) habits of adults with mental retardation. Prevalence of physical inactivity and recommended LTPA of adults with mild to moderate mental retardation who live in community settings was described. Adults with mental retardation (76 men, 74 women) reported their physical activity habits. Overall, men and women who resided in community settings were similarly inactive, with 47% to 51% of individuals participating in little to no LTPA. Forty-two to 47% of them reported participation in moderate to vigorous LTPA five or more times per week. Limitations to quantifying physical activity through questionnaire process is discussed and development and implementation of programs designed to increase physical activity levels recommended.

This paper reviews age related changes in body fat, fat-free body mass, and the subcomponents of FFM including protein, mineral, and body water. It gives an overview of common methods and their limitations in the elderly and reviews the effects of physical activity on body composition in middle-aged and older individuals. Surprisingly little information is available on this important topic in men and women >80 years of age. Although research to date has described a number of qualitative trends with aging and shown the correlations between changes in fat and FFM with disease risk, quantification of rate of change has proven difficult. This is partly because changes in the aging body affect the indicators of body composition, leading to estimation errors, and because few long-term longitudinal studies have been completed. The increasing awareness of the important relationships among health, nutrition, and body composition, and the profound change in population demographics projected for the next 25 to 50 years, has focused attention on this problem and will undoubtedly stimulate additional research in this area.

Previous studies have shown that children have a higher aqueous fraction of the fat-free body mass (FFM) than young adults. In older adults, methodological differences among studies limit evaluation of potential age-related differences in the water content of the FFM (W/FFM). Therefore, we determined W/FFM in 28 healthy white prepubescent children (age = 5–10 yr), 31 young adults (age = 22–39 yr), and 62 older adults (age = 65–84 yr), using 2H2O dilution to estimate total body water and a multicomponent approach based on body density, total body water, and regional bone mineral density to estimate FFM. To quantify the extent to which variation in W/FFM affects percent fat estimation error, differences in percent fat between our multicomponent approach and the Siri two-component model were related to W/FFM. Prepubescent children (72.7 +/- 1.6%) and older adults (72.5 +/- 1.4%) were found to have significantly higher (P < 0.01) mean W/FFM than young adults (70.8 +/- 1.2%). Differences in percent fat between the multicomponent and two-component models ranged from -10 to 6% fat and were significantly associated with W/FFM (r = -0.62, P < 0.0001). We conclude that prepubescent children and older adults, on average, have a higher W/FFM than young adults, and that, in adults, individual differences in W/FFM account for a substantial portion of the percent fat estimation errors associated with the use of two-component body composition models.

BACKGROUND. Recent studies have shown considerable variation in body fatness among children and adolescents defined as obese by a percentile rank for skinfold thickness. METHODS. We examined the relationship between percent body fat and risk for elevated blood pressure, serum total cholesterol, and serum lipoprotein ratios in a biracial sample of 3320 children and adolescents aged 5 to 18 years. Equations developed specifically for children using the sum of subscapular (S) and triceps (T) skinfolds were used to estimate percent fat. The S/T ratio provided an index of trunkal fat patterning. RESULTS. Significant overrepresentation (greater than 20%) of the uppermost quintile (UQ) for cardiovascular disease (CVD) risk factors was evident at or above 25% fat in males (32.2% to 37.3% in UQ) and at or above 30% fat in females (26.6% to 45.4% in UQ), even after adjusting for age, race, fasting status, and trunkal fat patterning. CONCLUSIONS. These data support the concept of body fatness standards in White and Black children and adolescents as significant predictors of CVD risk factors. Potential applications of these obesity standards include epidemiologic surveys, pediatric health screenings, and youth fitness tests.

(2006). Agreement in Body Fat Estimates Between a Hand-Held Bioelectrical Impedance Analyzer and Skinfold Thicknesses in African American and Caucasian Adolescents. Research Quarterly for Exercise and Sport: Vol. 77, No. 4, pp. 519-526.

Purpose: To develop an historical bone loading questionnaire that assesses loads applied to the skeleton using bone loading units and to determine its reproducibility. Additional purposes were to correlate bone loading units with areal bone mineral density (aBMD) and to determine whether low levels of bone loading increase the odds for low aBMD in healthy premenopausal women. Methods: Premenopausal women (N = 80; age: 31 +/- 7.7 yr) completed the newly developed bone loading history questionnaire (BLHQ) twice within 4-6 wk to establish reproducibility. aBMD (g[middle dot]cm-2) of the whole body, lumbar spine (L2-4), and right hip (proximal femur) were assessed with dual energy x-ray absorptiometry (DXA) in the women. Results: The questionnaire demonstrated good test-retest reliability in premenopausal women using intraclass correlation coefficients (spine r = 0.89, P < 0.001; hip r = 0.92, P < 0.001). Total spine bone loading exposure (r = 0.338; P = 0.002) and hip bone loading exposure (r = 0.317; P = 0.004) were significantly and independently correlated with femoral neck aBMD, after adjusting for BMI. Logistic regression analyses revealed increased odds for low femoral neck aBMD among those in the lowest tertile for recent hip bone loading exposure after adjusting for older ages, oral contraceptive use, low calcium intake, and an overweight BMI (OR = 3.62; CI = 1.09-11.94; P = 0.035). Conclusion: Historical bone loading activity can be reliably assessed and is moderately associated with femoral neck aBMD. This questionnaire could help to identify women with low femoral neck aBMD prior to menopause.

To determine the relations among peak aerobic capacity, physical activity, functional ability, components of the metabolic syndrome (high-density lipoprotein cholesterol [HDL-C], triglycerides [TG], glucose, insulin, abdominal obesity, high blood pressure), and inflammatory factors (interleukin-6 [IL-6], C-reactive protein [CRP]) in men with paraplegia.Cross-sectional exploratory design.University research laboratory.Twenty-two men (age, 39+/-9y; duration of injury, 17+/-9y; level of injury, T2-L2) with functionally complete paraplegia volunteered to participate.Not applicable.Peak aerobic capacity was measured using a graded peak exercise test with an arm ergometer, and physical activity was assessed by the Physical Activity and Disability Scale. Functional ability was assessed by the Self-Report Functional Measure. Circulating glucose, insulin, HDL-C, TG, total cholesterol, IL-6, and CRP levels were determined by specific enzyme or immunologic assays. Body fat was determined by dual-energy x-ray absorptiometry, and central obesity was estimated from abdominal sagittal diameters.Lower peak aerobic capacities were associated with lower HDL-C and lower physical activity levels ( P.014). Lower physical activity levels were associated with higher fasting glucose, lower HDL-C level, and larger abdominal sagittal diameters ( P.036). Larger abdominal sagittal diameters were associated with higher fasting glucose, higher fasting and postload insulin, lower HDL-C, higher TG, and higher CRP levels ( P.05).Diet and exercise trials are needed to determine the efficacy and effectiveness of lifestyle interventions aimed at slowing the progression of the metabolic syndrome in people with spinal cord injury.

Background and Objectives The pain following total knee arthroplasty can be associated with significant morbidity, especially in the elderly. Regional anesthetic techniques attenuate or eliminate postoperative pain, which may reduce this morbidity. Methods A 74-year-old patient with history of an epidural abscess underwent elective bilateral total knee arthroplasty for degenerative joint disease. Bilateral lumbar plexus catheters were placed via the fascia iliaca compartments. Lidocaine was infused postoperative through both catheters, and serum lidocaine levels were followed. Results The patient received significant postoperative pain relief based on physical and subjective examination. There were no complications or untoward effects related to the technique. Conclusion Lumbar plexus blockade with continuous local anesthetic infusion via the fascia iliaca compartment is an effective means of providing postoperative analgesia after total knee arthroplasty when epidural analgesia is contraindicated.

Due to age-related decreases in bone minera11,2 and total body protein3 coupled with a possible increase in the hydration of the fat-free mass (1,1-M)4, it is likely that, on average, the density of the FFM is lower in older relative to younger adults. Other investigators have speculated that the density of the FFM may become more variable with advancing age5,6. In either case, erroneous estimates of body fat percentage (%Fat) will result when traditional two-component (2C: fat and fat-free) models7 are used in older adults. More complex four component (4C: fat, water, mineral and fat-free residual) models3,5,8 may provide more valid substitutes for the 2C model7 in older adults.

The relationship of skinfold thicknesses and body density to body fatness was assessed, and skinfold prediction equations were developed for the estimation of body fatness determined from measures of body density, total body water, and bone mineral in a sample of 91 males and 116 females aged 34-84 years. For a given skinfold thickness, adjustment for individual deviations in the water and bone mineral fractions of the fat-free body assumed constant by traditional body composition models resulted in absolute reductions in overstimates of body fatness from 4.5 to 1.9% in females and from 2.8 to 1.7% in males for every 15 year increase in age. Percentage fat from density, water, and bone was estimated from skinfold thicknesses with SEEs of 2.9% in males and 3.8% in females. When compared to percentage fat from our multicomponent-derived criterion, percentage fat from body density and a two-component model resulted in individual errors ranging from underestimates of 5.6% fat to overestimates of 14.0% fat. The multicomponent prediction equations presented herein should produce more valid estimates of body composition in middle-aged and older men and women than equations based on two-component models. © 1992 Wiley-Liss, Inc.

The association between physical activity, dietary behaviors, and elevated cardiovascular disease risk factor components of the insulin resistance syndrome in adults with mental retardation was identified. Established clinical cutoff points were used to identify 145 participants with mild mental retardation and hyperinsulinemia, borderline high triglycerides, low high-density lipoprotein cholesterol, hypertension, and abdominal obesity. Odds ratios were calculated from logistic regression analysis. Those who participated in more frequent bouts of physical activity or who consumed lower dietary fat intakes were approximately one third as likely to have hyperinsulinemia and abdominal obesity compared to those who participated in less frequent physical activity or who consumed higher fat intakes, suggesting that these behaviors are protective against elevated components of the insulin resistance syndrome.

A reduced expression of the insulin resistance syndrome, a common neuroendocrine disorder underlying atherosclerosis, may play a role in reduced atherosclerosis in adults with Down syndrome. We compared selected components of the insulin resistance syndrome between 75 adults with Down syndrome and 70 with mental retardation due to other causes. After adjusting for age differences, residence, cigarette smoking, and medication use, women with Down syndrome had lower fasting plasma glucose and lower systolic blood pressure than comparison women. Men with Down syndrome had lower systolic and diastolic blood pressure than comparison men. Results suggest that women with Down syndrome may be less likely to express the insulin resistance syndrome, and men and women with Down syndrome may possess fewer atherosclerotic risk factors than the comparison groups.

The ability ofdual-energy x-ray absorptiometry (DEXA) to detect small changes in body composition was studied in I 7 men and women during a dehydration-rehydration pro- tocol. Scale weight (BW) and total mass (TM) from DEXA were highly related (r > 0.99) as were estimates of fat-free mass (r = 0.99) and percent fat (r = 0.97) from DEXA and densitometry. Changes in BW of � 1.5 kg due to fluid loss and gain were highly correlated (r = 0.90) with both changes in TM and soft-tissue mass (STM) by DEXA but less so (r = 0.67) with changes in lean-tissue mass (LTM). Mean changes in TM. STM. and LTM were not different (P > 0.05) from changes in BW. Estimates of bone mass and fat were unaffected by changes in hydration. We conclude that DEXA is able to detect small individual changes in TM and STM and is also useful for detecting group changes in LTM. .�1m J ('/in Nutr 1993:57:845-50.