The effect of aerobic exercise on self-esteem and depressive and anxiety symptoms among breast cancer survivors.

PURPOSE/OBJECTIVES: To evaluate the effects of 10 weeks of aerobic exercise on depressive and anxiety symptoms and self-esteem of breast cancer survivors. DESIGN: Experimental, crossover. SETTING: Midwestern university town. SAMPLE: Twenty-four breast cancer survivors (mean time following surgery 41.8 months; ranging from 1 to 99 months) recruited via mail and cancer support groups. The mean age of the sample was 48.9 years. METHODS: Subjects were assigned randomly into exercise (EX), exercise-plus-behavior modification (EX + BM), and control groups. EX and EX + BM groups exercised aerobically four days/week at > or = 60% of age-predicted maximum heart rate for 10 weeks. Data were collected pretest, post-test, and crossover (12 weeks following post-test). Because pretest or post-test scores showed no statistical differences between EX and EX + BM groups, data were combined to form one group. MAIN RESEARCH VARIABLES: Aerobic exercise (four days/ week; 30-40 minutes/session), depression, (Beck Depression inventory), anxiety (Speilberger State-Trait Anxiety Inventory), and self-esteem (Rosenberg Self-Esteem Inventory). FINDINGS: Pre- to post-test analyses revealed that women who exercised had significantly less depression and state and trait anxiety over time compared to controls. After the crossover, the control group demonstrated comparable improvements in both depressive and state anxiety scores. Self-esteem did not change significantly. Subjects who received exercise recommendations from their physicians exercised significantly more than subjects who received no recommendation. CONCLUSIONS: Mild to moderate aerobic exercise may be of therapeutic value to breast cancer survivors with respect to depressive and anxiety symptoms but not to self-esteem. A physician's recommendation to exercise appears to be an important factor in a patient's exercise adherence. IMPLICATIONS FOR NURSING PRACTICE: To Improve depressive and anxiety symptoms following breast cancer surgery, healthcare professionals should consider recommending mild to moderate exercise.

Relationship between insulin resistance and abnormal lipid profile in obese adolescents.

OBJECTIVE: To determine whether the lipid abnormalities observed in obese adolescents are associated with insulin resistance. METHODS: We evaluated the relationship between lipid levels and insulin resistance in 82 obese adolescents. Insulin resistance was assessed by fasting insulin level and sum of the insulin values after an oral glucose tolerance test in all 82, and were compared with data from 40 nonobese adolescents. Whole-body glucose uptake during euglycemic hyperinsulinemia (M value) was performed in 19 of the obese adolescents and compared with that of 24 nonobese young adults. RESULTS: The obese adolescents had significantly elevated low-density lipoprotein cholesterol (LDL-C) (3.09 +/- 0.73 mmol/L; 119 +/- 28.2 mg/dl) and triglycerides (1.22 +/- 0.62 mmol/L; 108 +/- 54.6 mg/dl) and low high-density lipoprotein cholesterol (HDL-C) levels (0.94 +/- 0.24 mmol/L; 36 +/- 9.1 mg/dl) when compared with values in the nonobese subjects. M values were significantly depressed in the obese compared with the nonobese subjects. Adiposity significantly correlated with low HDL-C and elevated triglyceride values. From the variables representing insulin resistance, the strongest correlation with the abnormal lipid profile was found for the M value. A stepwise multiple regression analysis revealed that the M value was the only step entered into the relationship for triglycerides and LDL-C, and both M value and fasting insulin were entered for HDL-C. CONCLUSION: In obese adolescents the degree of insulin resistance explains a significant portion of the variance in the levels of triglycerides, LDL-C, and HDL-C.

Individuals with amyotrophic lateral sclerosis are in caloric balance despite losses in mass.

The purpose of this study was to quantify body composition changes during amyotrophic lateral sclerosis (ALS) progression and to determine whether these subjects were losing or maintaining the energy stored in their bodies. The body composition of 12 males in the early stages of ALS and 6 age-matched controls was measured twice over a 6-month period using dual X-ray absorptiometry. During the study period the control group did not change. The ALS group lost an average of 2 kg of lean mass while gaining 0.55 kg of fat mass, resulting in a 1.45 kg loss in total body mass. When the changes in mass were converted to their energy equivalents, the ALS subjects lost an average of 1800 kcal of energy stored in lean mass but gained 4900 kcal in fat mass, resulting in a net increase of 3100 kcal stored. In conclusion, a small increase in fat mass can successfully compensate for the energy lost in lean mass from disease progression. Therefore, it is possible to preserve the amount of energy stored in the body of ALS patients, even when there are significant losses in lean and overall body mass. Consequently, a moderate loss of body mass should be expected and even encouraged among this patient population.

Validity of a new portable indirect calorimeter: the AeroSport TEEM 100.

The purpose of this study was to compare oxygen uptake (VO2) values collected with a new portable indirect calorimeter (AeroSport TEEM 100 Metabolic Analysis System) against a more traditional large calorimeter system that has been reported to be valid and reliable (SensorMedics 2900 Metabolic Measurement Cart). Minute ventilations ranging from rest up to heavy exercise were compared with simultaneous measurements from a 120-1 Tissot gasometer. Each of the three TEEM 100 pneumotachs were tested. Three hundred and sixty-one separate ventilation tests were performed using the low-flow, medium-flow, and high-flow heads of the portable calorimeter. For each of the pneumotachs, the correlation between the portable calorimeter values and the gasometer values exceeded r = 0.94. The standard error of estimate for the low-medium- and high-flow pneumotach were 5.96, 4.89 and 9.0%, respectively, expressed relative to the mean gasometer value. Simultaneous measurements of VO2 using the portable calorimeter and the SensorMedics 2900 unit were compared during rest and at work rates starting at zero watts, increasing by 25 W to 150 W. Each work rate was of 4 min duration. The average of data from minutes 3 and 4 were used in all analyses. There was very close agreement between the two metabolic measurement systems. Except at the 100-W work rate, where the VO2 difference was small (3.9%), yet statistically significant, all of the other differences in VO2 were small and non-significant. The scatter plot of VO2 for the SensorMedics versus the portable Aero-Sport calorimeter revealed close agreement; the correlation was r = 0.96, (SEE = 3.95%).(ABSTRACT TRUNCATED AT 250 WORDS)

Reliability and within subject variability of VE, VO2, heart rate and blood pressure during submaximum cycle ergometry.

To assess the reliability and within subject variability of steady-rate ventilation (VE), oxygen uptake (VO2), heart rate, systolic and diastolic blood pressure, 4 subjects exercised for 10 minutes at 3 work rates on a bicycle ergometer: 50 W, 125 W and 55% of maximum work rate (55% max). Each testing session included two work rates and only 2 testing sessions were scheduled per week. The order of the work rates was counterbalanced. In 8 to 10 weeks, 3 of the subjects completed 20 trials at 50 W while the fourth subject completed 11 trials, and all the subjects completed 10 trials at 125 W and 55% max. The within subject variability (S2w) was expressed as a percent of the mean steady-rate response. VO2 ranged from 21.2% to 27.5% of VO2max at 50 W, from 37.7% to 49.7% at 125 W and from 42.9% to 63.7% at 55% max. The S2w averaged 6.8% for VE, 4.3% for VO2, 3.2% for heart rate, 7.3% for systolic blood pressure and 10.5% for diastolic blood pressure. Reliability coefficients were calculated for the steady-rate scores by dividing the between subject variation by the total variation. The reliability was similar for VE, VO2 and heart rate and ranged from r = 0.69 to r = 0.97. Systolic and diastolic blood pressure reliabilities were lower and ranged from r = 0.27 and r = 0.80. In summary, the steady-rate ventilation, oxygen uptake and heart rate responses were reliable and consistent. The reliability of blood pressure was low. It is possible that this low reliability may result from variability in stroke volume or total peripheral resistance.

Urine sodium excretion in response to an oral glucose tolerance test in obese and nonobese adolescents.

To determine if physiologic changes of insulin are capable of inducing sodium retention in insulin-resistant patients, we evaluated the ability of an oral glucose tolerance test to alter urine sodium excretion in 32 obese subjects (13.3 +/- 1 years, weight 82 +/- 5 kg, mean arterial pressure 89.3 +/- 1.5 mm Hg) and 13 nonobese subjects (13.8 +/- 2 years, weight 46 +/- 4 kg, mean arterial pressure 74.5 +/- 2.6 mm Hg). After an overnight fast, subjects were placed in water diuresis and fasting insulin and glucose levels were drawn. Three 30-minute urine collections were obtained for baseline urine sodium excretion. The oral glucose tolerance test was administered with glucose and insulin levels drawn at 15, 30, 45, 60, 90, and 120 minutes. During the oral glucose tolerance test, four 30-minute urine collections were obtained for urine sodium excretion. Serum glucose levels at baseline and throughout the glucose tolerance test did not differ between obese and nonobese subjects. Baseline insulin levels were elevated significantly in the obese (20 +/- 3 microU/mL) compared with the nonobese (5 +/- 0.7 microU/mL) subjects. Furthermore, insulin levels remained significantly elevated in the obese subjects compared with the nonobese subjects throughout the glucose tolerance test (118 +/- 19 vs 49 +/- 6 microU/mL, obese vs nonobese subjects at 1-hour post-glucose tolerance test).(ABSTRACT TRUNCATED AT 250 WORDS)

Hemodynamic responses to upright exercise of adolescent cardiac transplant recipients.

To characterize the hemodynamic response to exercise after cardiac transplantation, we asked seven adolescent transplant patients (aged 15.1 +/- 0.7 years; mean +/- SE) to perform upright discontinuous exercise to volitional exhaustion on a mechanically braked cycle ergometer. Data were compared with those of seven control subjects matched for age, gender, body mass, percentage of fat, and body surface area. The transplant group had lower peak power output values (92 +/- 13 vs 146 +/- 30 watts; p less than or equal to 0.001) and maximum oxygen consumption values (22 +/- 8 vs 32 +/- 8 ml/kg per minute; p less than or equal to 0.03), despite achieving the same peak venous lactic acid concentration (6.2 +/- 3 vs 5.9 +/- 3 mEq/L; p = not significant). The transplant group had a diminished heart rate in response to exercise--44% lower than the control group had (delta = 49 +/- 6.4 vs 87 +/- 9.1 beats/min; p = 0.005). The cardiac output response to exercise was maintained in the transplant group (delta = 6.5 +/- 1.5 vs 4.6 +/- 0.8 L/min; p = not significant) by an augmented stroke volume response (delta = 31 +/- 10 vs -4 +/- 3.4 ml; p = 0.01), which may relate to a greater decrease in systemic vascular resistance during exercise (delta = -13.7 +/- 2.2 vs -6.3 +/- 1.2 Wood units; p = 0.02). Thus adolescents who have undergone cardiac transplantation have a normal cardiac output response to upright exercise. This is accomplished, despite a blunted heart rate response, by an augmented stroke volume that may relate to the greater decrease in systemic resistance during exercise.

Forearm resistance vessel abnormalities and insulin resistance in obese adolescents.

To determine if structural changes in forearm resistance vessels are associated with insulin resistance, we evaluated the relation between minimum forearm vascular resistance and insulin resistance in 95 obese adolescents before and after weight loss. Insulin resistance was assessed by fasting insulin levels and sum of insulin values after an oral glucose tolerance test in all 95 subjects and whole body glucose uptake during euglycemic hyperinsulinemia in 35 of 95 subjects. Structural changes in forearm vessels were assessed by measurement of minimum forearm vascular resistance during 10 minutes of ischemic exercise. As compared with our normal values, obese adolescents had a significantly (p less than 0.01) decreased maximal forearm blood flow (41.6 +/- 1.4 versus 67.1 +/- 2.4 ml/min/100 ml) and increased minimum forearm vascular resistance (2.9 +/- 0.4 versus 1.6 +/- 0.7 mm Hg/ml/min/100 ml). There was a significant relation (p less than 0.01) between minimum forearm vascular resistance and fasting insulin, sum of insulins, and whole body glucose uptake. After a 20-week weight-loss program, minimum forearm vascular resistance decreased (3.0 +/- 0.3 versus 2.0 +/- 0.2, p less than 0.01), maximal forearm blood flow increased (41 +/- 2.3 versus 57.4 +/- 3.9, p less than 0.01), and forearm volume remained unchanged. We also observed a significant (p less than 0.01) relation between the decrease in minimum forearm vascular resistance and the decrease in fasting insulin (r = 0.29), decrease in sum of insulins (r = 0.42), and increase in whole body glucose uptake (r = 0.63).(ABSTRACT TRUNCATED AT 250 WORDS)

Reduced short-term thermic effects of a meal in obese adolescent girls.

Post-meal energy expenditure (TEM) was compared for 14 healthy obese (body fat = 45.3%, body mass index, BMI = 35.9 kg m-2) and 9 healthy nonobese (body fat = 20.7%, BMI = 17.8 kg m-2) adolescent girls. The test meal for both groups was a standard 3348.8-kJ, 0.473-1 chocolate milkshake of 15% protein (casein), 40% fat (polyunsaturated/saturated ratio = 0.05; 75 mg cholesterol) and 45% carbohydrate (lactose and sucrose). Glucose, insulin and resting energy expenditure (RMR) were measured at rest prior to meal consumption and 20, 40, 60, 90, and 120 min after the meal. Cumulative net TEM was calculated as the integrated area under the TEM curve with RMR as baseline. Reliability was assessed by retesting 4 subjects, and a placebo effect was tested by administering a flavored energy-free drink. Results indicated high reliability and no placebo effect. The meal resulted in a greater rise in insulin and glucose for the obese compared to the nonobese subjects (P < or = 0.05), and a significant TEM for both groups (P < or = 0.05). The cumulative TEM (W kg-1) was 61.9% greater for the nonobese (P < 0.01) when expressed relative to body mass, and 33.2% greater for the nonobese (P < or = 0.01) when expressed relative to the fat-free body mass. Expressed relative to the meal, the TEM was 25.5% less for the obese (P < 0.01). The data support an energy conservation hypothesis for obese female adolescents.

Gender dimorphism in size, shape and body composition of child-onset obese and nonobese adolescents.

Gender dimorphism (percent GD) for stature (S), body size, body mass (BM) distribution and body composition for obese and nonobese male and female adolescents (mean age 12.7 years, range 10.5-14.5) was compared for 22 girths, 13 bony widths, five skin + fat folds (SF), fat mass (FM), fat free mass (FFM), body density (Db), and calculated variables (BMI, BSA, unit-size mass, waist:hip ratio (WHR), and FFM/S). BM distribution was computed with the ponderal mass equivalent somatogram. There was significant (P less than or equal to 0.05) percent GD for FM, FFM, Db, for the nonobese, but not obese. Only the neck, forearm and wrist girths revealed small but significant (P less than or equal to 0.05) percent GD for the obese. There was no girth percent GD for the nonobese. The elbow, wrist and ankle diameters revealed significant (P less than or equal to 0.05) percent GD for the obese; there was no significant percent GD for the nonobese for the same bony widths. Only the subscapula and iliac SF revealed significant (P less than or equal to 0.05) percent GD for the obese. For nonobese, percent GD was significant (P less than or equal to 0.05) for the triceps, subscapula and thigh SF, Comparisons between obese and nonobese indicated significant (P less than or equal to 0.05) differences between obese and nonobese males and females for FM, FFM, all girths and SF, but not S. Surprisingly, the obese and nonobese had nearly identical trunk diameters; the sum of biacromion, chest, biilac, and bitrochanter diameters were different by only 4.6 percent (n.s.) for the obese and nonobese males, and 1.3 percent (n.s.) for the obese and nonobese females. Thus, a large central frame-size cannot be used to justify the acquisition or maintenance of a larger than average BM for the obese. The ponderal equivalent analyses revealed that the obese's abdomen was the size of a person projected to have a BM in excess of 100 kg. The use of surface anthropometry in the study of adolescent obesity was supported.

Relationships of body size, segmental dimensions, and ponderal equivalents to muscular strength in high-strength and low-strength subjects.

There are conflicting results in prior studies concerning the relationships among body size, muscle size, and muscular strength. The purpose of the present study was to evaluate how body size, body shape, and segmental dimensions related to individual differences in muscular strength. Subjects were tested on four dynamic measures of strength and then classified into one of two groups as high strength (HS; N = 21) and low strength (LS; N = 21). Individual differences in strength were then related to body composition and segmental anthropometry. Strength was assessed during high-resistance, low-velocity standing squat and supine bench press with an isokinetic dynamometer, and during seated bench press and knee extension with a hydraulic resistance dynamometer. Anthropometry and body composition included 11 girths, six fatfolds, predicted fat-free mass (FFM), thigh and upper arm volume, muscle + bone cross-sectional area (CSA), and the Behnke Ponderal Somatogram (PSom) body profiling system. There was a 21.3% difference in strength between HS and LS (p less than 0.05), but no significant differences in age, stature, and fatfolds. MANOVA revealed that seven of 11 girth components of PSom were larger for HS (p less than 0.05). The correlations between strength vs body mass, FFM, thigh and upper arm volume, and CSA and fatfolds in HS and LS ranged from r = -0.52 to 0.56 (r = -0.70 to 0.70 when corrected for restriction of range). We conclude that individual differences in muscular strength are poorly related to various measures of body size and segmental body dimensions.

Proprioceptive facilitation of muscle tension during unilateral and bilateral knee extension.

The effects of double neuromuscular facilitation (DNF) in unilateral movements and of quadruple neuromuscular facilitation (QNF) in bilateral movements were studied in 42 physically active college-age male subjects. Results showed a 10.4% significant increase of maximal knee extension torque output when unilateral extension was preceded by a knee flexion on an isokinetic exerciser and a 16.7% increase of maximal torque in the bilateral condition of simultaneous alternating flexion-extension when compared to the simultaneous extension movement. Consequently, the increased peak torque observed in the unilateral and bilateral experimental conditions in which knee extension was preceded by a knee flexion appears to be the result of a combination of neuromuscular influences and stored elastic energy.

Reliability and validity of the Omnitron hydraulic resistance exercise and testing device.

This study assessed the measurement reliability and validity of the Hydra-Fitness Omnitron, a microprocessor-controlled isokinetic ergometer that provides concentric resistance for dynamic extension and flexion movements as well as resistance for isometric contractions. Maximal peak torque output measured by the Omnitron and strain gauge devices connected to the apparatus were compared in 26 physically active males who were tested over 3 days for isometric knee extension and isokinetic knee flexion/extension at two resistance levels. Maximal torque outputs remained stable on days 2 and 3 (p less than 0.05), and intraclass reliability yielded r = 0.94 to 0.98. There was no difference between the slopes of the regression lines for the different experimental conditions (p less than 0.05). There was significant improvement between day 1 and days 2 and 3 that corresponded to a combination of a training and learning effect. Thus, one practice session was necessary to obtain reliable individual differences. The validity correlations between peak torque output measured from the Omnitron and strain gauges were greater than r = 0.94. There was a small discrepancy (0.44 to 0.88 Nm) between the two measuring devices that can be explained by the difference in shank pad positioning that accommodates for different segment lengths. We conclude that reliability and validity were excellent over a wide range of torque outputs measured during maximal isometric and maximal dynamic double concentric flexion and extension movements.

Insulin and renal sodium retention in obese adolescents.

The effect of insulin on the renal handling of sodium was studied in obese and nonobese subjects by using euglycemic hyperinsulinemia. Seven water-loaded obese (14-19 years old) and five nonobese young adults (18-21 years old) had insulin given intravenously at a rate of 40 munits/m2/min. Blood glucose and creatinine clearance were not altered by euglycemic hyperinsulinemia in either the obese or the nonobese group. Hyperinsulinemia resulted in a significant decrease in urinary sodium excretion in both groups of subjects (by 54.2 +/- 3% [mean +/- SEM] in the obese and by 50.9 +/- 3.1% in the nonobese group). However, the amount of glucose required to maintain euglycemia was significantly less in the obese versus nonobese group, 89.5 +/- 6.2 versus 329.2 +/- 16 mg glucose/m2/min (p less than 0.001). There was no relation in either group between the amount of glucose required to maintain euglycemia and the change in urinary sodium excretion. On a separate day, all of the obese subjects underwent 3 hours of water diuresis but without insulin. There was no change in urinary sodium excretion with sustained water diuresis alone. However, when compared with the nonobese group, the obese group of subjects had a significantly higher resting mean arterial pressure, heart rate, and plasma norepinephrine concentration; during the insulin clamp, neither group experienced a significant change in mean arterial pressure or heart rate, and only the nonobese group experienced an increase in plasma norepinephrine. In obese subjects, we have found, despite the presence of insulin resistance to carbohydrate metabolism, that euglycemic hyperinsulinemia was associated with a normal decrease in urinary sodium excretion.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of weight loss on the sensitivity of blood pressure to sodium in obese adolescents.

To clarify the role of sodium intake in the regulation of blood pressure in obese subjects, we measured blood pressure in 60 obese and 18 nonobese adolescents after successive two-week periods of a high-salt diet (greater than 250 mmol of sodium per day) and a low-salt diet (less than 30 mmol per day). When they were changed from a high-salt to a low-salt diet, the obese group had a significantly larger mean change (+/- SE) in mean arterial pressure (-12 +/- 1 mm Hg) than did the nonobese group (+1 +/- 2 mm Hg; P less than 0.001). The variables that best predicted the degree of sodium sensitivity were the fasting plasma insulin level, the plasma aldosterone level while the low-salt diet was being given, the plasma norepinephrine level while the high-salt diet was being given, and the percentage of body weight made up by fat. Fifty-one of the obese adolescents were also studied before and after a 20-week weight-loss program. After the weight-loss program, the 36 subjects who lost more than 1 kg of body weight had a reduced sensitivity of blood pressure to sodium (difference from value during high-salt diet to that during low-salt diet, -1 +/- 1 mm Hg). The blood pressure of the remaining 15 adolescents was still sensitive to sodium intake (-11 +/- 3 mm Hg). These results support the hypothesis that the blood pressure of obese adolescents is sensitive to dietary sodium intake and that this sensitivity may be due to the combined effects of the hyperinsulinemia, hyperaldosteronism, and increased activity of the sympathetic nervous system that are characteristic of obesity.

Physiological responses to nine different exercise:rest protocols.

This study determined the metabolic responses to different exercise:rest protocols during circuit exercise using hydraulic resistance. In experiment 1, nine subjects underwent nine different 27 min exercise circuits. There were three variations of three exercise:rest protocols (2:1, 1:1, 1:2). The VO2 for the nine circuits averaged (mean +/- SEM) 1.94 +/- 0.03 l.min-1 (43% of treadmill VO2max), with the largest difference between the protocols being 13%. Heart rate averaged 152.2 +/- 3.1 beats.min-1, with the largest difference between the protocols being 8%. Increasing the exercise duration per minute or the number of exercise bouts per minute had minimal effects on the mean VO2 and heart rate response to hydraulic resistive exercise. In experiment 2, nine subjects underwent three different 9 min exercise circuits using exercise:rest protocols of 2:1, 1:1, and 1:2 while work and VO2 were simultaneously measured. Surprisingly, increases in work were not necessarily accompanied by corresponding increases in VO2.

Strength gains in obese females are unaffected by moderate dietary restriction.

This study examined the effects of dietary restriction on strength gains from whole body resistance training. Comparisons were made between diet-restricted (n = 12) and non-diet-restricted (n = 10) obese women (mean +/- SD, 36.7 +/- 7.0% fat) undergoing identical 8-week resistance training regimens. Diet-restricted subjects reduced their dietary intake by 4200 kJ/day and reduced body mass by 3.9 kg over 8 weeks. Ten-repetition maximum masses were compared between the groups on biweekly intervals. Results indicated no differences between the groups with respect to the rate or magnitude of strength gains for any of the eight exercises. Significant pre- to post-test increases in strength (p less than 0.05) were found for all eight exercises. The rate or magnitude of strength gains induced by resistance training does not appear to be affected by moderate dietary restrictions in obese females.

Basal metabolism of obese adolescents: inconsistent diet and exercise effects.

Effects of 20 wk of diet-plus-behavior (DB) therapy or exercise-plus-diet-plus-behavior (EDB) therapy on changes in basal energy expenditure (BEE) were studied in 36 obese male and female adolescents. BEE was assessed by open-circuit spirometry and body composition by hydrostatic weighing. Dietary restriction was based on the dietary-exchange program. Behavioral treatment included record-keeping, stimulus-control, and reinforcement techniques. EDB therapy included 50 min/d, 3 d/wk of aerobics. A time-by-group (2 X 3) repeated-measures ANOVA was used to analyze pre-to-postintervention differences between groups (DB, EDB, and control). Results revealed small but statistically significant (p less than 0.05) differences in body composition between the two experimental groups and control subjects. There were no differences in body composition between the DB and EDB groups, although all control subjects gained body mass (p less than 0.05). There was no group-by-time interaction for BEE. Moderate correlations of r = less than or equal to 0.61 were obtained between change in BEE and change in body composition for the subjects in the experimental groups.

Blood pressure in obese adolescents: effect of weight loss.

The BP distribution of a group of 72 obese adolescents was determined both before and after weight loss. Weight loss was produced by a program of caloric restriction and behavior change alone (n = 26) or with a combination of caloric restriction, behavior change, and exercise (n = 25). It was demonstrated that obese adolescents have a BP distribution that is skewed 1 SD to the right of normal (P less than .01), and that with weight loss this distribution was no longer different from that of the general population. It was also shown that a weight loss program that incorporates exercise and caloric restriction produces the most desirable effect on BP reduction (ie, greatest decrease in resting systolic BP and greatest decrease in exercise diastolic and mean BP). Finally, it was demonstrated that obese adolescents have structural changes present in the forearm resistance vessels and that these structural changes are reversed to the greatest extent in the weight loss program that includes exercise.

Coronary risk incidence of obese adolescents: reduction by exercise plus diet intervention.

The incidence of coronary heart disease risk factors and the effects of 20 weeks of diet and exercise were studied in 36 obese adolescents. Values for the following risk factors were determined: serum triglyceride level, high-density lipoprotein-cholesterol level, total cholesterol level, systolic and diastolic BP, maximum work capacity, obesity, and presence of coronary heart disease in the family history. Of the subjects, 97% had four or more risk factors. Two subjects possessed all eight risk factors. The adolescents were randomly assigned to either a control, diet therapy and behavior change, or exercise, diet therapy, and behavior change group. From pre- to posttreatment, a 14.8% and 41.4% reduction in multiple risk was noted for the latter two groups, respectively. No significant difference between the control group and the diet and behavior change group was found. In contrast, the exercise-diet-behavior change group reduced multiple risk (P less than .01) more than either of the other groups. It was concluded that obese adolescents are at high risk for the development of coronary heart disease and that exercise in addition to moderate dietary restriction can result in the reduction of multiple coronary heart disease risk.