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To determine whether an exercise intervention using an active video game (Dance Dance Revolution [DDR]) is effective in improving endothelial dysfunction (EDF) and other risk factors in overweight children.Thirty-five children (Body mass indexor = 85(th) percentile, mean age 10.21+/-1.67 years, 17 females) with EDF were assessed for flow-mediated dilation (FMD), lipids, insulin, glucose, NO(2)+NO(3), asymmetric dimethylarginine, symmetric dimethylarginine, l-arginine, height, weight, aerobic fitness, and blood pressure. In a subsample, tumor necrosis factor alpha, interleukin-6, C-reactive protein, and adiponectin were also assessed. Subjects were randomly assigned to 12-weeks of aerobic exercise (EX) using DDR or to a non-exercising delayed-treatment control group (DTC).EX had significant improvements in FMD ( 5.56+/-5.04% compared with 0.263+/-4.54%, p=0.008), exercise time on the graded exercise test (53.59+/-91.54 compared with -12.83+/-68.10 seconds, p=0.025), mean arterial pressure (MAP) (-5.62+/-7.03 compared with -1.44+/-2.16 mmHg, p=0.05), weight (0.91+/-1.53 compared with 2.43+/-1.80 kg, p=0.017) and peak VO(2) (2.38+/-3.91 compared with -1.23+/-3.18 mg/kg/min, p=0.005) compared with the DTC. Thirteen EX subjects achieved normal EDF while ten did not. These groups differed at baseline with regard to total cholesterol (TC) and low-density lipoprotein (LDL).Twelve weeks of DDR-use improved FMD, aerobic fitness, and MAP in overweight children. Improvements occurred without changes in inflammatory markers or nitric oxide production. The results document the need to explore relationships between obesity, endothelial function, inflammation, lipids, exercise intensity, and gender in a larger sample of overweight children.

It is not known whether myosin heavy chain (MHC) content changes in response to exercise training or creatine supplementation in subjects with Charcot-Marie-Tooth disease (CMT). Based on previous data, we hypothesized that resistance exercise and creatine would increase the percentage of type I MHC composition in the vastus lateralis muscle and that myosin isoform changes would correlate with improved chair rise-time in CMT subjects. To test this hypothesis, 18 CMT subjects were randomly assigned to either a placebo or creatine group. All subjects performed a 12-week, home-based, moderate-intensity resistance training program. Chair rise-time was measured before and after the training program. Muscle biopsies were obtained from the vastus lateralis before and after the 12-week program. Gel electrophoresis showed a significant decrease (approximately 30%) in MHC type I in CMT subjects given creatine supplementation when compared with placebo. There was a nonsignificant increase in both MHC type IIa (approximately 23%) and MHC type IIx (approximately 7%) in CMT subjects given creatine. Reduced MHC type I content and increased MHC type IIa content correlated with faster chair rise-times (i.e., improved muscle performance). The training-induced change in MHC IIa content was inversely correlated with chair rise-time in CMT subjects given creatine. When the two subject groups were combined, there was a linear, negative relationship between the change in MHC type IIa content and chair rise-time after training and a positive relationship between the training-induced change in MHC type I content and chair rise-time. These data suggest that improved function (chair rise-time) was associated with a lower level of MHC type I and increased MHC type IIa composition. Furthermore, the data are consistent with the hypothesis that creatine supplementation alters MHC composition in CMT patients undergoing resistance training and that MHC changes associated with creatine supplementation can improve muscle function.

Objectives: Bacillus Calmette-Guerin (BCG) is the treatment of choice for carcinoma in situ of the bladder, but its application to other cancers is very limited. The current study evaluates the effect of intralesional BCG in the PA3 rat prostate cancer model. Materials and Methods: One hundred five rats were randomized to four groups. Each group received 1 × 106 PA3 cells subcutaneously on experiment Day 0. On experimental Day 7, the groups received the first of six weekly treatments. Treatments consisted of saline solution, BCG 1 × 104 colony-forming units (cfu), BCG 1 × 105 cfu, and BCG 1 × 106 cfu. All animals were monitored for tumor growth throughout the duration of the experiment. Results: Animals receiving treatments with BCG 1 × 106 cfu exhibited the greatest reduction in tumor volume ([mean ± SD] 4130.0 ± 1738.3 mm3; p = 0.0738), followed by those receiving BCG 1 × 104 cfu (4527.6 ± 1932.7 mm3; p = 0.1093) and BCG 1 × 105 cfu (4838.2 ± 1889.9 mm3; p = 0.5218), compared to those receiving the saline solution control (5445.0 ± 3119.5 mm3). Animal survival on Day 60 after transplantation was significantly increased in the group receiving BCG 1 × 106 cfu (19 [73.1%] of 26 animals; p = 0.0326) when compared to those receiving the saline solution control (12 [44%] of 27 animals). Treatment with BCG 1 × 105 cfu (11 [42.3%] of 26 animals survived; p = 0.5479) and BCG 1 × 104 cfu (13 [50%] of 26 animals survived; p = 0.4484) also reduced survival compared to the saline solution control, but not to the level of significance. Conclusions: The consistent reduction in tumor growth and animal mortality in animals receiving intralesional BCG demonstrates antitumor activity in this aggressive model of prostate cancer. The greatest efficacy was seen with the highest dose of BCG, suggesting that higher doses may be optimal in this model. BCG immunotherapy of prostate cancer warrants clinical evaluation.

to examine the effect of cycle phase or a low dose oral contraceptive on exercise performance in young women.As controls, 15 men were tested twice by a maximal treadmill test (Vo2 max) and by an endurance run 14 d apart to determine performance variability from causes other than hormonal fluctuations. Ten women ages 18-30 were then tested for Vo2 max and endurance in the same way in both the follicular and the luteal phase (random order, ovulation assessed by sonography). They were then randomly assigned to placebo (n = 3) or oral contraceptive (1 mg norethindrone and 35 micrograms ethinyl oestradiol) (n = 7) for 21 days. Tests were repeated during the first and third weeks of treatment. Vo2 max and endurance tests were compared in the men and control cycle of the women by using independent t tests on percent change. The data for both cycles in the women were analysed by repeated measures ANOVA.There was no difference in per cent change in total test time, Vo2 max, or breathing frequency between the men and women in either test. Data obtained during the Vo2 max test revealed no difference between the follicular and luteal phases of the menstrual cycle for total test time [11.8 (SD 2.3) v 12.6 (2.3) min], Vo2 [41.6 (12.1) v 39.7 (11.4) ml.kg-1.min-1], or breathing frequency [26.8 (3.5) v 27.3 (9.9) breaths.min-1] respectively, or during the first and third weeks of treatment [total test time 12.0 (2.5) v 12.8 (2.4) min; Vo2 37.3 (7.4) v 41.0 (12.4) ml.kg-1.min-1; breathing frequency 27.8 (4.2) v 27.7 (3.4) breaths.min-1, respectively]. Data obtained during the endurance test revealed no difference between the follicular and luteal phase of the menstrual cycle for total test time [20.5 (15.7) v 16.2 (8.5) min], Vo2 [37.5 (9.4) v 32.9 (8.1) ml.kg-1.min-1], or breathing frequency [32.0 (6.0) v 33.2 (5.1) breaths.min-1, respectively], or during the first and third weeks of treatment [total test time 32.3 (34.9) v 30.6 (30.1) min; Vo2 33.9 (10.1) v 35.2 (8.6) ml.kg-1.min-1; breathing frequency 34.0 (5.9) v 34.8 (5.3) breaths.min-1, respectively].Neither cycle phase nor a low dose oral contraceptive containing 1 mg norethindrone adversely affects performance during a maximal treadmill test or endurance run.The authors examined the effect of cycle phase or a low dose oral contraceptive on the exercise performance of young women. As controls, 15 men were tested twice by a maximal treadmill test and by an endurance run 14 days apart to determine performance variability from causes other than hormonal fluctuations. 10 women aged 18-30 were then tested by maximal treadmill test and endurance in the same manner in both the follicular and luteal phase. They were then randomly assigned to placebo or oral contraceptive for 21 days. Tests were repeated during the first and third weeks of treatment. Maximal treadmill test and endurance tests were compared in the men and control cycle of women using independent t tests on percent change. Neither cycle phase nor a low dose oral contraceptive containing 1 mg norethindrone was found to adversely affect performance during a maximal treadmill test or endurance run.

The hamster has been the accepted model of emphysema since the 1970s, demonstrating disease-related effects on respiratory skeletal muscle. However, there is scant information available about the model's ability to replicate the peripheral skeletal muscle changes seen in human disease, such as alterations in capillarity. The present study described the capillary-to-fiber ratio (C/F) of normal hamster plantaris, gastrocnemius, and soleus muscles in eight animals. C/F was 1.72 ± 0.38 for plantaris, 1.95 ± 0.40 for gastrocnemius, and 2.22 ± 0.43 for soleus. C/F of soleus was significantly greater (P < 0.01) than plantaris. The C/F of hamster hindlimb muscles varies from those seen in rat species, and having baseline data on hamsters makes it possible to determine the effects of emphysema on C/F in this model. Anat Rec Part A 277A:272–274, 2004. © 2004 Wiley-Liss, Inc.

The purpose of this study was to profile waist-to-hip ratios and cardiovascular disease (CVD) risk factors in mildly-obese younger American women. Sixty sedentary, nonsmoking, premenopausal, healthy women 21 to 51 years of age participated in the study. Peak oxygen consumption (VO2), percent body fat, waist-to-hip ratios, and lipid profiles were determined. Subjects were then grouped according to waist-to-hip ratio for statistical analyses, wherein android had waist-to-hip ratios of >m 0.8 (n = 19) and gynoid < 0.8 (n = 41), respectively. The groups were not different with respect to age, peak VO2, and body mass. Gynoid had lower blood pressure at rest and during maximal exercise compared to android. Additionally, gynoid had lower percentage body fat, smaller subscapular and suprailiac skinfold measurements, and waist circumference than android. Android had higher total cholesterol, LDL-C, triglycerides, apoprotein B, and insulin compared to gynoid. HDL-C was not different between the groups. Significant correlations of low-to-moderate magnitude were observed between % fat and blood pressure, and between waist-to-hip ratio and cholesterol, triglycerides, LDL-cholesterol, apoprotein B, and insulin. Subscapular skinfolds were related to blood pressure and cholesterol, LDL-cholesterol, triglycerides, insulin, and apoprotein B. A positive relationship existed between insulin and blood pressure and triglycerides while a negative relationship existed between HDL-cholesterol and blood pressure. These data suggest that centralized obesity is associated with an increased risk of developing CVD as evidenced by higher blood pressure, less desirable lipid profiles, and higher serum insulin.

Level of physical activity has been found to be an independent risk factor for coronary heart disease. Because lifestyle and dietary habits are frequently established by early adulthood, we examined the physical activity, physical fitness, body composition, plasma lipids, and diets of a group of second-year medical students. Medical students were studied because of the presumption that they were knowledgeable about exercise and appropriate diet and would have future influence on their patients. A questionnaire which assessed physical activity was returned by 69 (89%) of the 80 students. Over 50% reported no hard or very hard physical activity either during the week or on weekends. Three subjects were smokers. Body composition, cardiovascular fitness, and plasma lipids were assessed in 20 subjects selected at random from the 69. Five of the 15 men, but none of the five women, had greater-than-desirable body fat. Cardiovascular fitness was at least average compared to normal values, but three had hypertension at rest and 12 had hypertensive responses to exercise. Seven of the men had LDL cholesterol above 130 mg/dl and three had LDL:HDL ratios greater than 3. There was a positive correlation (r = 0.5, p = 0.02) between hard/very hard activity assessed by questionnaire and VO2max and a negative correlation (r = 0.4, p = 0.05) between VO2max and percent fat. All 20 subjects reported above average to severe amounts of stress. Analysis of a 48-hr diet record of 22 students showed an average consumption of 47% carbohydrates, 17% protein, and 36% fat. The polyunsaturated/saturated ratio was 0.43.(ABSTRACT TRUNCATED AT 250 WORDS)

Emphysema has been associated with loss of aerobic muscle fibers and decreased blood supply. However, when these changes begin and whether exercise can prevent these changes is unknown. The purpose of this study was to examine peripheral muscle at different time points during the development of emphysema and to determine the additional effects of muscle activity. In a series of 3 experiments, emphysema was induced in hamsters. Exercise was simulated through surgical overload (OV) of the plantaris muscle of one leg. Animals were sacrificed at 1, 3, and 5 months following emphysema induction. Fiber type composition and capillary-to-fiber ratio (CFR) were determined. There were no significant changes in fiber type composition in the 1-month group. A significant increase in type IIA fiber composition (mean 72.0 vs. 54.5%) and decrease in type IIB fiber (mean 13.3 vs. 28.1%) was seen in the non-overloaded muscles following 3 months. In the 5-month group, there was a significant decrease in percentage of type I fibers (mean 14.7 vs. 28.0%). There were no significant differences in fiber type composition in the OV limb, regardless of duration. The CFR was significantly lower in the OV limb after 5-months of emphysema (mean 0.92 vs. 1.55 cap/fiber). Muscle overload prevented emphysema-associated changes in fiber type composition, but not in CFR. Peripheral muscle is affected early in the course of emphysema and chronic overload may play an important role in preserving normal muscle composition.

Utilization of very-low-calorie diets (VLCD) for weight loss results in loss of lean body weight (LBW) and a decrease in resting metabolic rate (RMR). The addition of aerobic exercise does not prevent this. The purpose of this study was to examine the effect of intensive, high volume resistance training combined with a VLCD on these parameters.Twenty subjects (17 women, three men), mean age 38 years, were randomly assigned to either standard treatment control plus diet (C+D), n = 10, or resistance exercise plus diet (R+D), n = 10. Both groups consumed 800 kcal/day liquid formula diets for 12 weeks. The C+D group exercised 1 hour four times/week by walking, biking or stair climbing. The R+D group performed resistance training 3 days/week at 10 stations increasing from two sets of 8 to 15 repetitions to four sets of 8 to 15 repetitions by 12 weeks. Groups were similar at baseline with respect to weight, body composition, aerobic capacity, and resting metabolic rate.Maximum oxygen consumption (Max VO2) increased significantly (p0.05) but equally in both groups. Body weight decreased significantly more (p0.01) in C+D than R+D. The C+D group lost a significant (p0.05) amount of LBW (51 to 47 kg). No decrease in LBW was observed in R+D. In addition, R+D had an increase (p0.05) in RMR O2 ml/kg/min (2.6 to 3.1). The 24 hour RMR decreased (p0.05) in the C+D group.The addition of an intensive, high volume resistance training program resulted in preservation of LBW and RMR during weight loss with a VLCD.

There is controversy over whether exercise and/or exercise intensity has an effect on total caloric intake or diet composition. The purpose of this study was to test the effect of exercise intensity without dietary manipulation on body composition and/or weight loss and to determine whether exercise intensity affected total caloric intake or diet composition in normal weight young women.Fifteen women aged 18 to 34 years with a maximal oxygen consumption average or below on the Palo Alto norms served as subjects. Subjects were randomly assigned to: 1) low heart rate intensity exercise group (LI, N = 7) which exercised 40 to 45 minutes approximately four times weekly at a mean heart rate of 132 beats per minute (bpm); 2) high heart rate intensity group (HI, N = 8) which exercised 40 to 45 minutes approximately four times weekly at a mean HR of 163 bpm. All subjects were given a maximal exercise test prior to and during weeks eight, 12 and 16. The first 4 weeks served as a control period, followed by approximately 11 weeks of exercise. Each subject recorded her dietary intake for 1 complete week, including a weekend, during weeks 2, 6, 10 and 14 of the study.VO2 max increased (p.05) in HI (29 +/- 6 ml/kg/minute to 38 +/- 7) but did not change in LI (36 +/- 5 to 38 +/- 7). Percent fat decreased in HI (p.05) (27 +/- 7 to 22 +/- 4) but was unchanged in LI (22 +/- 6 to 21 +/- 6). The weekly intake of total kcal, carbohydrate, protein and fat did change significantly for either group. The weekly intake of saturated fat declined significantly (p.05) in HI (21.2 +/- 5.8 g to 14.9 +/- 5.5 g); their weekly intake of cholesterol also decreased (p.05) between months 2 to 3 (249 +/- 109 mg to 159 +/- 58 mg). No other differences in dietary intake between groups were found.High heart rate intensity exercise training without dietary manipulation resulted in a decrease in body fat, but not weight change, as well as a decrease in the intake of saturated fat and cholesterol in normal weight young women. These changes were not observed after low heart rate intensity training.

The acute effects of two psychological stressors (personally stressful imagery and threat of shock) on blood glucose (BG), heart rate, blood pressure, skin conductance, and subjective stress were studied in 22 noninsulin-dependent diabetic adults and nine healthy, nondiabetic subjects similar in age, weight, education and sex. The diabetic group's BG rose significantly after threat of shock (M change from rest = 18.4 mg/dL, p < .05), although the nondiabetic group's BG remained stable throughout the assessment. Significant increases in subjective stress ratings (p < .05) and skin conductance level (p < .05) paralleled the noninsulin-dependent diabetes mellitis (NIDDM) subjects' BG response to threat of shock. The findings suggest that some stressors can have hyperglycemic effects on individuals with NIDDM, although generalization of these findings to the natural environment remains to be demonstrated. The methodology used is contrasted with other studies that have failed to demonstrate stress effects on BG.