Search

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.

Dehydroepiandrosterone (DHEA) has an antiobesity effect in rodents, and elevated endogenous levels of its sulfate ester (DHEAS) are associated with reductions in risk for cardiovascular disease (CVD) in men. To examine the association of body fat and fat distribution, established correlates of CVD and CVD risk factors, with circulating DHEAS levels in women, we measured trunk and limb skinfold thicknesses and circumferences, total and regional body fat from dual energy x-ray absorptiometry (DXA), and serum levels of DHEAS in 96 healthy Caucasian females aged 28-39 yr. Body mass index, percentage fat from DXA and the waist-to-hip ratio were not significantly correlated (ror = 0.15, Por = 0.156) with serum DHEAS levels, regardless of statistical control for age, smoking behavior, and fasting status. However, the ratio of trunk/total skinfold thicknesses (r = 0.23, P = 0.030) and the percentage of total fat located on the trunk from DXA (r = 0.32, P = 0.002) were positively correlated with DHEAS, whereas the ratio of leg/total skinfold thicknesses (r = -0.25, P = 0.015) and the percentage of total fat located on the legs from DXA (r = -0.25, P = 0.015) were inversely correlated with DHEAS after adjusting for age, smoking, and fasting status. With the exception of the trunk/total skinfold thickness ratio, the correlations of DXA- and skinfold-derived estimates of fat distribution remained significant (Por = 0.033) even after further adjustment for percentage fat or body mass index. It is concluded that increased amounts of total fat located on the trunk and decreased amounts of total fat located on the legs are associated with increased serum DHEAS concentrations in normally menstruating females.

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.

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.

We tested the hypothesis that exercise training (Ex) attenuates the effects of hyperlipidemia on endothelial function by enhancing NO-mediated vasorelaxation in porcine brachial (Br) arteries. Adult female pigs were fed a normal-fat (NF) or high-fat (HF) diet for 20 wk. Four weeks after initiation of the diet, pigs underwent Ex or remained sedentary (Sed) for 16 wk. Relaxation to ACh was impaired by HF ( P = 0.03). The combination of HF and Sed impaired ACh-induced relaxation more than HF or Sed alone ( P = 0.0002). Relaxation to high doses of bradykinin (BK) was impaired by HF ( P = 0.0002). Ex significantly improved ACh-induced relaxation ( P = 0.01) and tended to improve relaxation to BK ( P = 0.38). To determine the mechanism(s) by which HF and Ex affected relaxation to ACh and BK, relaxation was assessed in the presence of N G-nitro-l-arginine methyl ester (l-NAME; to inhibit NO synthase), indomethacin (Indo; to inhibit cyclooxygenase), or l-NAME + Indo. In the presence of l-NAME, Indo, or l-NAME + Indo, ACh-induced relaxation was no longer different between HF and NF arteries; however, relaxation remained greater in Ex than in Sed arteries. In the presence of l-NAME or Indo, BK-induced relaxation was no longer altered by HF but was enhanced by Ex. In the presence of l-NAME + Indo, BK-induced relaxation was enhanced by HF and Ex. These data indicate that hyperlipidemia impairs ACh- and BK-induced relaxation by impairing NO- and PGI2-mediated relaxation. Ex attenuates the effects of HF by enhancing a vasodilator mechanism independent of NO and PGI2.

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.