Bacillus subtilis DE111 intake may improve blood lipids and endothelial function in healthy adults.

Cardiovascular disease (CVD) is the leading cause of death in the US and worldwide. By 2030 it is anticipated that CVD will claim the lives of more than 24 million people. Throughout the last decade, researchers have investigated the role of the gut microbiota in the development of CVD. Evidence exists for a positive correlation between Bifidobacterium and vascular function, glucose tolerance, and reduced systemic inflammation. Another probiotic species, Bacillus subtilis, has also been found to reduce cholesterol levels in human and animal models. In light of these data, we examined various measures of cardiovascular health after consumption of Bifidobacterium animalis subsp. lactis strain BL04, with and without a cocktail of Escherichia coli-targeting bacteriophages (marketed as PreforPro), Bacillus subtilis strain DE111 or a maltodextrin-based placebo in a healthy human population. In a randomised, double-blind, placebo-controlled 4-week intervention conducted in individuals 18 to 65 years of age with a body mass index of 20 to 34.9, we saw no significant changes in measured CVD parameters among individuals consuming B. lactis with or without bacteriophages. However, B. subtilis supplementation resulted in a significant reduction in total cholesterol relative to baseline measures (-8 mg/dl; P=0.04, confidence interval (CI): -13.40, -0.19), as well as non-high-density lipoprotein-cholesterol (-11 mg/dl; P=0.01, CI: -12.43, -2.07). In addition we observed trending improvements in endothelial function (P=0.05, CI: -0.003, 0.370) and in low-density lipoprotein-cholesterol (P=0.06, CI:-12.29, 0.2864). Strikingly, these effects were seen in a largely healthy population. These data suggest that B. subtilis supplementation may be beneficial for improving risk factors associated with CVD. Further studies in populations of older adults or those with dyslipidaemia and endothelial dysfunction is warranted.

Relationship of pressure to be thin with gains in body weight and fat mass in adolescents.

BACKGROUND: Sociocultural pressure to be thin is commonly reported by adolescents; yet, to what extent such pressure is associated with weight gain has not been evaluated longitudinally. OBJECTIVE: Examine whether pressure to be thin was positively associated with weight and fat gain in adolescents. METHODS: Participants were 196 healthy adolescent (age 15 ± 1 years old) girls (65%) and boys of varying weights (BMI 25 ± 7 kg/m2 ) studied at baseline and 1-year follow-up. At baseline, adolescents and their mothers reported pressure to be thin by questionnaire. At baseline and follow-up, BMI was calculated, and fat mass was assessed with air displacement plethysmography. Multiple regression was used to examine associations between baseline pressure to be thin and 1-year changes in BMI and fat mass. RESULTS: Accounting for multiple covariates, including baseline BMI or fat, adolescent-reported pressure from parents and peers and mother-reported pressure toward their teen were associated with greater gains in either adolescent BMI or fat (ps < .05). Adolescent weight status was a moderator of multiple effects (ps < .05). CONCLUSIONS: Parental and peer pressure to be thin were associated with increases in BMI and fat mass during adolescence, particularly in heavier adolescents. Further research is necessary to clarify how this association operates reciprocally and to identify underlying explanatory mechanisms.

Inherent capacity for lipogenesis or dietary fat retention is not increased in obesity-prone rats.

Obesity results from positive energy balance and, perhaps, abnormalities in lipid and glycogen metabolism. The purpose of this study was to determine whether differences in lipogenesis, retention of dietary fat, and/or glycogenesis influenced susceptibility to dietary obesity. After 1 wk of free access to a high-fat diet (HFD; 45% fat by energy) rats were separated on the basis of 1 wk body weight gain into obesity-prone (OP; > or =48 g) or obesity-resistant groups (OR; < or =40 g). Rats were either studied at this time (OR1, OP1) or continued on the HFD for an additional 4 wk (OR5, OP5). Weight gain and energy intake were greater (P < or = 0.05) in OP vs. OR at both 1 (53 +/- 2 vs. 34 +/- 1 g; 892 +/- 27 vs. 755 +/- 14 kcal) and 5 (208 +/- 7 vs. 170 +/- 7 g; 4,484 +/- 82 vs. 4,008 +/- 72 kcal) wk, respectively. Rats were injected with (3)H(2)O and were either provided free access to an HFD meal containing labeled fatty acids (fed; n = 10 or 11/group) or were fasted (n = 10/group) overnight. The amount of food or (14)C tracer eaten overnight was equivalent between OP and OR rats. In liver, the fraction of (3)H retained in glycogen or lipid was not significantly different between OR and OP groups. Retention of dietary fat in the liver was not increased in OP rats. In adipose tissue, retention of (3)H was approximately 49% greater (P < or = 0.05) in OP1 vs. OR1 and approximately 30% greater in OP5 vs. OR5, but retention of dietary fat was not elevated in OP vs. OR. At the same time, fat pad weight (sum of epididymal, retroperitoneal, mesenteric) was 49% greater in OP1 rats vs. OR1 rats and 65% greater in OP5 vs. OR5 rats (P < or = 0.05). Thus a greater capacity for lipogenesis or retention of dietary fat does not appear to be included in the OP phenotype. The characteristic increase in energy intake associated with OP rats appears to be necessary and critical to accelerated weight and fat gain.

Influence of moderate chronic wine consumption on insulin sensitivity and other correlates of syndrome X in moderately obese women.

Epidemiologic studies indicate that alcohol consumption is associated with improved insulin sensitivity; however, scant experimental evidence confirms this observation. To determine the effects of regular moderate wine consumption on insulin sensitivity, 20 overweight women (body mass index [BMI], 29.8 +/- 2.2 kg/m2) participated in a 20-week free-living randomized crossover trial. The subjects, serving as their own controls, consumed wine (190 mL red wine, 13% vol/vol ethanol, 5 days per week) for 10 weeks and abstained for 10 weeks or vice versa. The dependent variables (body weight, BMI, percent body fat, blood pressure, fasting blood glucose and insulin, blood lipids, dietary intake, and insulin sensitivity by intravenous glucose tolerance test [IVGTT]) were measured at the pretest, at the 10-week crossover, and at the 20-week completion of the study. Data were analyzed at the pretest and at completion of the wine drinking and abstention periods of the study using ANOVA by order of treatment. Fasting glucose remained unchanged (mean +/- SD; P > .05) throughout the experiment (pretest, drinking, and abstention, 91.1 +/- 9.2, 91.6 +/- 9.1, and 88.5 +/- 11.2 mg/dL), as did the measures of insulin sensitivity, fasting insulin (pretest, drinking, and abstention, 8.6 +/- 3.3, 8.6 +/- 4.1, and 9.1 +/- 4.7 microU/mg) and the insulin sensitivity index (3.60 +/- 2.96, 3.25 +/- 2.17, and 3.30 +/- 1.84). Body composition and blood lipids also remained unchanged (P > .05) during treatment. Moderate wine consumption at this dose in overweight women did not improve or impair insulin sensitivity, nor did it change any of the known correlates of insulin sensitivity, including body weight and composition, blood lipids, and blood pressure.

Fat oxidation, lipolysis, and free fatty acid cycling in obesity-prone and obesity-resistant rats.

Defects in fat metabolism may contribute to the development of obesity, but what these defects are and where they occur in the feeding/fasting cycle are unknown. In the present study, basal fat metabolism was characterized using a high-fat diet (HFD)-induced model of obesity development. Male rats consumed a HFD (45% fat, 35% carbohydrate) ad libitum for either 1 or 5 wk (HFD1 or HFD5). After 1 wk on the HFD, rats were separated on the basis of body weight gain into obesity-prone (OP, > or =48 g) or obesity-resistant (OR,

Effect of acute resistance exercise on postexercise oxygen consumption and resting metabolic rate in young women.

This study determined the effect of an intense bout of resistive exercise on postexercise oxygen consumption, resting metabolic rate, and resting fat oxidation in young women (N=7, ages 22-35). On the morning of Day 1, resting metabolic rate (RMR) was measured by indirect calorimetry. At 13:00 hr, preexercise resting oxygen consumption was measured followed by 100 min of resistive exercise. Postexercise oxygen consumption was then measured for a 3-hr recovery period. On the following morning (Day 2), RMR was once again measured in a fasted state at 07:00. Postexercise oxygen consumption remained elevated during the entire 3-hr postexercise recovery period compared to the pre-exercise baseline. Resting metabolic rate was increased by 4.2% (p<.05) from Day 1 (morning prior to exercise: 1,419 +/- 58 kcal/24hr) compared to Day 2 (16 hr following exercise: 1,479 +/- kcal/24hr). Resting fat oxidation as determined by the respiratory exchange ratio was also significantly elevated on Day 2 compared to Day 1. These results indicate that among young women, acute strenuous resistance exercise of the nature used in this study is capable of producing modest but prolonged elevations of postexercise metabolic rate and possibly fat oxidation.

Comparison of risk factors for obesity in young, nonobese African-American and Caucasian women.

OBJECTIVE: To determine whether specific risk factors for obesity were more evident in young, normal-weight African-American (AA) compared to Caucasian-American (CA) women. DESIGN: Cross-sectional age-matched study. SUBJECTS: Young, nonobese, sedentary AA (n= 13, 22.5y of age, 23.6% body fat) and CA women (n = 11, 21.5y of age, 24.0% body fat). MEASUREMENTS: Aerobic physical fitness (peak VO2), resting metabolic rate (RMR), resting and submaximal exercise fat oxidation rates, total daily energy expenditure (TDEE) by the doubly-labeled water method, physical activity energy expenditure (PAEE), skeletal muscle glycolytic (phosphofructokinase activity (PFK)) and beta-oxidative (beta-hydroxy-acyl CoA dehydrogenase (beta-HADH)) activity, and insulin sensitivity estimated by the insulin-augmented frequently sampled intravenous glucose tolerance test. RESULTS: The AA and CA subjects were similar in age, body mass index and body composition, but the AA women exhibited lower peak VO2. There were no group differences in RMR adjusted for body composition, or in the rates of submaximal exercise energy expenditure or fat oxidation, and no difference in skeletal muscle beta-HADH or PFK activity. The AA women exhibited lower insulin sensitivity and greater acute insulin response to glucose. The mean TDEE for the AA women was only 74% that of the CA women, primarily due to a lower physical activity energy expenditure (AA group: xPAEE = 1,246+/-438 kJ/day; CA group: x= 3,310+/-466 kJ/day. CONCLUSION: These data indicate that PAEE and its correlates of peak aerobic capacity and insulin sensitivity are lower in young, nonobese AA women compared to their CA counterparts.

Risk factors for cardiovascular disease and diabetes in two groups of Hispanic Americans with differing dietary habits.

OBJECTIVE: The purpose of this study was to determine if Hispanic Seventh-Day Adventists (SDAs), who typically eat a diet lower in fat, saturated fat and protein, and higher in complex carbohydrates and dietary fiber than the usual omnivorous diet, exhibit lower risk factors for cardiovascular disease (CVD) and Type 2 diabetes compared to Hispanic Catholic omnivores. METHODS: Anthropometric characteristics, dietary intake, blood pressure, serum lipids, glucose and insulin, as well as plasma ascorbic acid and vitamin E concentrations, were measured in two groups of Hispanic study participants residing in Denver, Colorado: 74 SDA study participants (x age: 42+/-1.5 y) and 45 Catholic participants (x age: 44+/-2.2 y). RESULTS: The SDAs reported lower dietary intakes of total fat, saturated fat and cholesterol and higher relative intakes of carbohydrate and dietary fiber compared to their Catholic counterparts. The SDAs exhibited significantly lower body mass index (BMI = 27.2+/-0.6) and waist-to-hip ratios (WHR = 0.84+/-0.01) compared to the Catholics (BMI = 31.4+/-1.1; WHR = 0.88+/-0.01). The SDAs, compared to the Catholics, had lower fasting insulin (11.4+/-0.6 vs. 18.9+/-3.1 microu/ml) and glucose concentrations (88.6+/-1.1 vs. 104.1+/-5.4 mg/dl). The SDA Hispanics, compared to the Catholic Hispanics, exhibited significantly lower values for systolic blood pressure (SBP = 1102 vs. 118+/-3 mm Hg), serum total cholesterol (STC = 198+/-5 vs. 214+/-6 mg/dl) and serum triglycerides (TG = 152+/-12 vs. 232+/-27) and higher serum concentrations of high-density lipoprotein cholesterol (HDL-C = 44.7+/-1.3 vs. 39.1+/-1.4 mg/dl) and ascorbic acid (1.14+/-0.08 vs. 0.87+/-0.07 mg/dl). Low-density lipoprotein cholesterol (LDL-C) and vitamin E concentrations were not significantly different between groups, but the SDAs exhibited lower ratios of STC/HDL-C and LDL-C/HDL-C. CONCLUSION: Hispanic American SDAs, who eat a plant-based diet, exhibit a more favorable blood lipid profile, lower blood pressure and lower risk for Type 2 diabetes compared to Hispanic American Catholics, who do not eat a plant-based diet.

Cardiovascular disease risk factors are lower in African-American vegans compared to lacto-ovo-vegetarians.

OBJECTIVE: This study was undertaken to determine if African-American strict vegetarians (vegans) exhibit lower blood pressure (BP) and a more favorable serum lipid profile than their lacto-ovo vegetarian (LOV) counterparts, and if plasma ascorbic acid (AA) concentrations could explain any group differences in these cardiovascular disease (CVD) risk factors. METHODS: Habitual dietary intake, anthropometric characteristics, blood pressure, and blood lipids and ascorbic acid concentrations were determined in African-American study participants (male vegans, n = 14, age = 45.6 years; male LOV, n = 49, age = 49.8; female vegans, n = 31, age = 51.1, female LOV, n = 94, age = 52.1) recruited from Seventh-Day Adventist Churches in several cities in the northeastern United States. RESULTS: Body mass index (BMI) was significantly lower in the vegans (24.7 +/- 1.9 kg/m2) compared to LOV (26.4 +/- 0.45 kg/m2). There were no diet or gender differences in BP. Serum total cholesterol (3.75 +/- 0.12 vs. 4.51 +/- 0.10 mmol/L), LDL-cholesterol (2.06 +/- 0.13 vs. 2.65 +/- 0.09 mmol/l), and triglycerides (0.94 +/- 0.07 vs. 1.17 +/- 0.04 mmol/L) were significantly (p < 0.05) lower in vegans compared to LOV, but there were no dietary group differences in HDL-C. The ratio of total to HDL-cholesterol was significantly lower in vegans than in LOV (3.0 +/- 0.13 vs. 3.7 +/- 0.13). There were no dietary group differences in plasma AA concentrations. However, in the entire sample, plasma AA was inversely associated with BP (SBP: r = -0.46, p < 0.001, DBP: r = -0.32, p < 0.001), but unrelated to the serum lipid concentrations. CONCLUSION: African-American vegans exhibit a more favorable serum lipid profile than lacto-ovo-vegatarians and plasma AA is inversely related to BP in African-American vegetarians but does not explain any of the differences in CVD risk factors between vegans and lacto-ovo vegetarians.

Stress fractures in female army recruits: implications of bone density, calcium intake, and exercise.

OBJECTIVE: To identify characteristics and factors associated with increased risk for stress fractures in military women. DESIGN: Case-control study to retrospectively examine physical activity, prior calcium intake, and bone density as predictors of stress fractures. SETTING: A military training installation which incorporates physical training for women. SUBJECTS: Forty-nine female soldiers with confirmed stress fractures (cases) and 78 female soldiers with no orthopedic injuries (controls), aged 18 to 33 years. MEASURES: Retrospective self-reports of habitual exercise, sports participation, and food intake; current height, weight, and body mass index (BMI); demographic variables (age, ethnicity, menstrual patterns, smoking habits); and bone density on radiologically defined stress fractures. RESULTS: Cases and controls were similar in height, weight, and BMI. Measurements of bone density (g/cm2) at the trochanter (cases, 0.77+/-0.09; controls, 0.77+/-0.08); femoral neck (cases, 0.94+/-0.10; controls, 0.94+/-0.09); Ward's triangle (cases, 0.91+/-0.11; controls, 0.93+/-0.11); lumbar spine (cases, 1.21+/-0.12; controls, 1.24+/-0.10); and radius shaft (cases, 0.67+/-0.09; controls, 0.68+/-0.05) were not different between groups. Calcium intake was not different between groups (cases, 1154+/-751 mg/day; controls, 944+/-513 mg/day) and did not correlate with bone density (r=0.01 to -0.06 at four sites). Sports participation positively correlated with bone density in the hip (r=0.49). Leisure activity energy expenditure (kcal/day) tended toward association with lower stress fracture risk as expenditure level increased (p=0.06). CONCLUSION: Stress fracture in female Army recruits was not correlated with bone density or calcium intake during adolescence, although a weak relationship to prior physical activity was observed.

Energy availability and mammary carcinogenesis: effects of calorie restriction and exercise.

The purpose of this experiment was to compare the carcinogenic response in the mammary gland among groups of rats whose energy metabolism had been modulated by restricting dietary calories and/or by increasing energy expenditure via exercise. Female F344 rats (n = 132) were injected i.p. with 1-methyl-1-nitrosomethylurea (50 mg/kg at 50 and 57 days of age) and were randomized into one of four treatment groups: (i) unrestricted, sedentary; (ii) calorie-restricted, sedentary; (iii) unrestricted, exercised; (iv) calorie-restricted, exercised. The targeted level of calorie-restricted was 20% and exercise was achieved by treadmill-running (20 m/min at a 15% grade for 30 min, 5 days/week). During the 20.5 week study, rats were palpated twice a week for detection of mammary tumors and urine was collected for determination of 24-h cortical steroid excretion. At the end of the study, all mammary lesions were histologically classified. Carcass composition and carcass energy were determined. Mammary carcinogenesis was inhibited among calorie-restricted, sedentary rats compared with unrestricted, sedentary rats (79% inhibition, P < 0.001). No inhibition of carcinogenesis was observed among exercised rats (unrestricted or calorie-restricted) relative to the unrestricted, sedentary rats. Within the present experimental design, exercise had no effect on carcinogenesis despite significant reductions of carcass fat and carcass energy among both groups of rats that exercised. Cortical steroid level was significantly higher only in calorie-restricted, sedentary rats (P < 0.05). These results do not support the hypothesis that reductions of body weight gain, carcass fat or carcass energy are sufficient conditions to inhibit mammary carcinogenesis. The results do suggest that changes in urinary cortical steroid excretion may predict whether an energy-related intervention is likely to alter mammary carcinogenesis.

Influence of moderate daily wine consumption on body weight regulation and metabolism in healthy free-living males.

OBJECTIVE: Although previous studies have clearly demonstrated that energy from alcohol may not be efficiently utilized to maintain body weight when it comprises 20% or more of the daily caloric intake, there is considerable debate regarding the influence of moderate alcohol consumption (< or = 5% of the total daily caloric intake) upon metabolism, substrate utilization and body weight regulation. Consequently, the objectives of this study were to determine whether moderate alcohol consumption could influence body weight via changes in substrate utilization, oxygen consumption or alterations in dietary macronutrient content. METHODS: Fourteen male subjects (mean age = 32.1 years) participated in a 12-week, free-living, crossover trial in which they either drank red wine (270 ml; 13% v/v ethanol) daily for 6 weeks and then abstained for the next 6 weeks or vice-versa. RESULTS: Whether wine was imbibed or not, no significant differences (p > 0.05) were demonstrated for any of the following variables: body weight, body fat percentage, skinfold thickness, resting metabolic rate, respiratory quotient, caloric intake, dietary macronutrient content, or fasting insulin or glucose concentrations. CONCLUSIONS: In free-living subjects over a 6-week period, the addition of two glasses of red wine to the evening meal does not appear to influence any measured variable which may adversely affect body weight or promote the development of obesity during this time period.

Postexercise energy expenditure and substrate oxidation in young women resulting from exercise bouts of different intensity.

OBJECTIVE: The effects of low and high intensity exercise, of similar energy output, on exercise and post-exercise energy expenditure and substrate oxidation were studied in eight active, eumenorrheic females (aged 22 to 31). METHODS: Continuous indirect calorimetry was performed during cycle ergometry exercise and for 3 hours following each of the following three protocols administered in random order: 1) low intensity exercise (LIE: 500 calories 50% VO2 max), 2) high intensity exercise (HIE: 500 calories 75% VO2 max), and 3) control condition (C) of quiet sitting for 1 hour, rather than exercise. Excess postexercise oxygen consumption (EPOC), energy expenditure and total fat and carbohydrate oxidation for the entire exercise/control plus 3-hour recovery period were determined by indirect calorimetry. RESULTS: Mean EPOC for the 3-hour post-exercise period for HIE (9.0 +/- 1.7 L, 41 kcals) was significantly greater than EPOC for low intensity exercise (4.8 +/- 1.6 L, 22 kcals). Oxygen consumption (VO2) following HIE, but not LIE remained elevated at the end of the 3-hour post-exercise period. Total carbohydrate oxidation (exercise plus postexercise period) was significantly higher for HIE (116 +/- 8.6 g) compared to LIE (85.0 +/- 5.2 g). Total fat oxidation was lower for HIE (27.7 +/- 3.3 g) compared to LIE (36.9 +/- 3.0 g), but this difference did not reach statistical significance (p = 0.07). At the end of the 3-hour recovery period, the rate of fat oxidation was higher following HIE compared to LIE. CONCLUSION: These data indicate that the recovery period should also be considered when determining the impact of different exercise intensities on total energy expenditure and fat and carbohydrate utilization in women.

Plasma ascorbic acid concentrations are related to cardiovascular risk factors in African-Americans.

This study was undertaken to examine relationships among blood pressure, blood lipids, and plasma concentrations of ascorbic acid and malondialdehyde (MDA) equivalents (indicative of lipid peroxidation) in adult African-Americans. Subjects (n = 172, mean age = 48.0 y) were recruited from among the memberships of several Seventh-Day Adventist Churches. Plasma ascorbic acid and MDA equivalents were inversely correlated (r = -0.44, P < 0.0001). There were significant inverse correlations between plasma ascorbic acid levels and both systolic (r = -0.39, P < 0.0001) and diastolic blood pressure (r = -0.25, P < 0.03), and between plasma ascorbic acid and serum total cholesterol (r = -0.25, P < 0.03), LDL-cholesterol (LDL-C) (r = -0.33, P < 0.004), and the ratio of LDL-cholesterol to HDL-cholesterol (LDL-C/HDL-C) (r = -0.32, P < 0.004). Serum HDL-cholesterol was positively related to plasma ascorbic acid (r = 0.22, P < 0.05). The correlations for MDA equivalents and the blood pressure and blood lipid variables were of similar magnitude to those of plasma ascorbic acid, but were in the opposite direction. Multiple regression analysis revealed ascorbic acid to be a significant independent contributor to the prediction of blood pressure and LDL-C concentration. These data suggest that plasma concentrations of ascorbic acid and MDA equivalents are related to several cardiovascular risk indicators in black Americans.

Interaction of acute changes in exercise energy expenditure and energy intake on resting metabolic rate.

The effects on resting metabolic rate (RMR) of energy intake and exercise energy expenditure were examined in eight trained men under four conditions: 1) high energy flux (HF), 90 min of exercise at 75% VO2max on 3 d while in energy balance; 2) low energy flux (LF), no exercise for 3 d while in energy balance; 3) negative energy balance (NEB), exercise on 3 d while consuming low-flux meals; and 4) positive energy balance (PEB), no exercise for 2 d while consuming high-flux meals. Eight untrained men were studied in LF. There were effects of exercise energy expenditure and energy intake on RMR, and an exercise x diet interaction (P < 0.05). RMR was greater in trained than in untrained subjects only when trained subjects were in HF. These data indicate that RMR is influenced by exercise, energy intake, and their interaction and suggest that higher RMR in trained vs untrained individuals results from acute effects of HF rather than from a chronic adaptation to exercise training.

The effects of aerobic and anaerobic exercise conditioning on resting metabolic rate and the thermic effect of a meal.

This study examined resting metabolic rate (RMR) and thermic effect of a meal (TEM) among athletes who had participated in long-term anaerobic or aerobic exercise. Nine collegiate wrestlers were matched for age, weight, and fat-free weight with 9 collegiate swimmers. Preliminary testing included maximal oxygen consumption, maximal anaerobic capacity (MAnC) for both the arms and the legs, and percent body fat. On two separate occasions, RMR and TEM were measured using indirect calorimetry. VO2max was significantly higher in the swimmers while MAnC was significantly higher in the wrestlers for both the arms and the legs. RMR adjusted for fat-free weight was not significantly different between groups. The differences in total and percentage of TEM between the groups were not statistically significant, and there were no differences in baseline thyroid hormones. These data suggest that despite significant differences in VO2max and WAnT values following long-term aerobic and anaerobic exercise training, resting energy expenditure does not differ between these college athletes.

Postexercise energy expenditure in response to acute aerobic or resistive exercise.

Postexercise energy metabolism was examined in male subjects age 22-35 years in response to three different treatments: a strenuous bout of resistive exercise (REx), a bout of stationary cycling (AEx) at 50% peak VO2, and a control condition (C) of quiet sitting. Resting metabolic rate (RMR) was measured the morning of and the morning following each condition. Recovery oxygen consumption (RcO2) was measured for 5 hr following each treatment. Total 5-hr RcO2 was higher for the REx treatment relative to both AEx and C, with the largest treatment differences occurring early during recovery. There were no large treatment differences in postexercise respiratory exchange ratio values, except for the first hour of recovery following REx. RMR measured 14.5 hr postexercise for the REx condition was significantly elevated compared to C. These results suggest that strenuous resistive exercise results in a greater excess postexercise oxygen consumption compared to steady-state endurance exercise of similar estimated energy cost.

Blood pressure and blood lipids among vegetarian, semivegetarian, and nonvegetarian African Americans.

Blood pressure (BP) and serum lipids were compared among three dietary groups of Seventh-day Adventist (SDA) African-American adults: vegetarians (VEGs: no consumption of animal flesh, n = 66), semivegetarians (SEMIVEGs: one to three servings of animal flesh per week, n = 56), and nonvegetarians (NONVEGs: daily consumption of animal flesh, n = 45). VEGs had a lower mean waist-to-hip ratio (WHR) and lower dietary intakes of protein, saturated fat, and cholesterol compared with the NONVEGs. Only 16% of the VEGs were confirmed to be hypertensive compared with 35.7% of the SEMIVEGs and 31.1% of the NONVEGs. Independent of differences in WHR, the VEGs had significantly lower concentrations of serum total cholesterol (STC), LDL-C, triglycerides, STC/HDL-C, and LDL-C/HDL-C than the NONVEGs. The SEMIVEGs had lipid values intermediate to the VEG and NONVEG groups. Among African-American SDAs, a vegetarian diet is associated with lower cardiovascular disease risk factors than is an omnivorous diet.

Resting metabolic rate and postprandial thermogenesis by level of aerobic fitness in young women.

Resting metabolic rate (RMR) and the thermic effect of a meal (TEM) were compared among women of three levels of aerobic fitness. Twenty-three euthyroid, eumenorrheic women (aged 18-35 years) were divided into three groups based on VO2 max standardized for fat-free weight (FFW), as determined from a graded exercise test: High Fit (HF): n = 7, VO2 max > 70 ml*kg FFW-1*min-1; Moderately Fit (MF): n = 8, VO2 max = 55-70 ml*kg FFW-1*min-1; and Low Fit (LF): n = 8, VO2 max < 55 ml*kg FFW-1*min-1). At 0700h RMR was measured for 1 h by indirect calorimetry with subjects in a fasted, preovulatory state, having refrained from exercise on the preceding day. The subject then consumed a liquid meal (12 kcal*kg FFW-1) and indirect calorimetry was continued for 3 h to determine the TEM. RMR adjusted for FFW using analysis of covariance was significantly higher (P < 0.05) in the HF group (mean +/- SEM = 1.08 +/- 0.03 kcal*min-1) compared to the MF (0.99 +/- 0.04) and LF (0.90 +/- 0.04) groups. Group differences in the thermic response did not reach statistical significance, although there was a trend for a high TEM in the HF group. There was a positive relationship between RMR and energy flux (average daily kcalorie intake + daily kcaloric expenditure in physical activity). These results suggest that women who exhibit high levels of exercise and aerobic fitness may be less energy efficient during the non-exercise portion of the day then their less active counterparts.

Blood pressure differences in older black and white long-term vegetarians and nonvegetarians.

The vegetarian diet has been associated with lower blood pressure (BP) in elderly white Americans. This study was undertaken to determine whether or not long-term adherence (at least 5 years) to a plant-based diet is similarly related to lower BP in older black Americans, a group exhibiting significant risk for hypertension (HT). Anthropometric characteristics, nutrient intake, and resting systolic and diastolic BP were measured in older black vegetarians (n = 27, age = 69.3 +/- 1.7 years), black nonvegetarians (n = 37, age = 65.4 +/- 1.2 years), white vegetarians (n = 85, age = 66.7 +/- 1.0 years), and white nonvegetarians (n = 54, age = 65.2 +/- 0.9 years). Older black vegetarians were significantly leaner and exhibited lower average systolic BP (131.4/76.8 mm Hg) and less hypertension than the black omnivores (141.6/76.2 mm Hg), but had significantly higher average BP than either dietary group of older white adults (vegetarians: 120.9/66.7 mm Hg; nonvegetarians: 122.8/67.6 mm Hg). These data suggest that long-term adherence to a vegetarian diet by older black Americans may afford some protection against hypertension, but in comparison to older white adults, does not completely offset their apparently greater susceptibility to untoward elevation of BP.