Dose-response relationships between exercise training volume and blood lipid changes suggest that exercise can favourably alter blood lipids at low training volumes, although the effects may not be observable until certain exercise thresholds are met. The thresholds established from cross-sectional literature occur at training volumes of 24 to 32 km (15 to 20 miles) per week of brisk walking or jogging and elicit between 1200 to 2200 kcal/wk. This range of weekly energy expenditure is associated with 2 to 3 mg/dl increases in high-density lipoprotein-cholesterol (HDL-C) and triglyceride (TG) reductions of 8 to 20 mg/dl. Evidence from cross-sectional studies indicates that greater changes in HDL-C levels can be expected with additional increases in exercise training volume. HDL-C and TG changes are often observed after training regimens requiring energy expenditures similar to those characterised from cross-sectional data. Training programmes that elicit 1200 to 2200 kcal/wk in exercise are often effective at elevating HDL-C levels from 2 to 8 mg/dl, and lowering TG levels by 5 to 38 mg/dl. Exercise training seldom alters total cholesterol (TC) and low-density lipoprotein-cholesterol (LDL-C). However, this range of weekly exercise energy expenditure is also associated with TC and LDL-C reductions when they are reported. The frequency and extent to which most of these lipid changes are reported are similar in both genders, with the exception of TG. Thus, for most individuals, the positive effects of regular exercise are exerted on blood lipids at low training volumes and accrue so that noticeable differences frequently occur with weekly energy expenditures of 1200 to 2200 kcal/wk. It appears that weekly exercise caloric expenditures that meet or exceed the higher end of this range are more likely to produce the desired lipid changes. This amount of physical activity, performed at moderate intensities, is reasonable and attainable for most individuals and is within the American College of Sports Medicine's currently recommended range for healthy adults.

Background Tai Chi Chuan (TCC) is an integrative medicine mind-body practice with a physical activity component that has positive effects on aerobic capacity, muscular strength, and quality of life among cancer survivors, similar to the effects elicited by other modes of moderate intensity exercise. Inflammatory cytokines, and insulin and insulin-related signaling molecules may contribute to weight gain and affect cancer recurrence rates and survival; exercise can curb cancer- and treatment-related weight gain, increase survival, and reduce levels of insulin and inflammatory cytokines. Despite knowing the beneficial effects of conventional exercise interventions on these mediators, little is known about the physiologic effects of TCC, a mind-body practice with a physical activity component, on these pathways in breast cancer survivors. Methods We assessed the effects of a 12-week, moderately intense, TCC intervention (n=9) compared to a non-physical activity control (n=10) consisting of psychosocial support therapy (PST) on levels of insulin, IGF-1, IGFBP-1, IGFBP-3 and cytokines IL-6, IL-2, and IFN-γ in breast cancer survivors. Results Levels of insulin are significantly different in TCC and PST groups; levels remained stable in the TCC group, but increased in the PST control group (p=0.099). Bivariate analysis revealed novel and significant correlations (all r >0.45, all p≤0.05) of both decreased fat mass and increased fat-free mass with increased IL-6 and decreased IL-2 levels. Conclusions This pilot study shows that TCC may be associated with maintenance of insulin levels and changes in cytokine levels that may be important for maintenance of lean body mass in breast cancer survivors.

Oceanic macroaggregates (marine snow and Rhizosolenia mats) sampled from the Sargasso Sea are associated with bacterial and protozoan populations up to four orders of magnitude greater than those present in samples from the surrounding water. Filamentous, curved, and spiral bacteria constituted a higher proportion of the bacteria associated with the particles than were found among bacteria in the surrounding water. Protozoan populations were dominated numerically by heterotrophic microflagellates, but ciliates and amoebas were also observed. Macroaggregates are highly enriched heterotrophic microenvironments in the oceans and may be significant for the cycling of particulate organic matter in planktonic food chains.

Background-Elevated C-reactive protein (CRP) is associated with increased coronary heart disease (CHD) risk.Cardiorespiratory fitness ("fitness") is related with lower CHD risk; however, its relationship with CRP is relatively unknown. Methods and Results-Cross-sectional associations between fitness and plasma CRP were examined among 135 African American (AA), Native American (NA), and Caucasian (CA) women (55Ϯ11 year; 28Ϯ6 kg/m 2 ). Fitness was assessed with a maximal treadmill exercise test. Plasma CRP concentrations were determined with the Dade Behring high-sensitivity immunoassay. Geometric mean CRP levels were 0.43, 0.25, and 0.23 mg/dL, and average maximal MET levels of fitness were 7.2, 9.1, and 10 METs for AA, NA, and CA, respectively. CRP decreased across tertiles of fitness (Pϭ0.002), increased across tertiles of BMI (Pϭ0.0007), and varied by race (Pϭ0.002). After adjustment for covariates, lower CRP (PϽ0.05) was observed across tertiles of fitness among NA and CA, but not AA. Among all women, after adjusting for race and covariates, the odds of high-risk CRP (Ͼ0.19 mg/dL) were 0.67 (95% CIϭ0.19 to 2.4) among fit (Ͼ6.5 METs) versus unfit women. Key Words: exercise Ⅲ C-reactive protein Ⅲ coronary disease Ⅲ women Ⅲ inflammation C -reactive protein (CRP) is a marker of subclinical inflammation. Elevated CRP is associated with a 2-to 5-fold increased risk of coronary events. 1,2 CRP is inversely related with insulin sensitivity, 3 directly related with type 2 diabetes risk, 4 and elevated among individuals with excessive body fat. [3][4][5] Fewer data exist on CRP and health for women and race-ethnic minorities, among whom CHD, diabetes, and obesity incidence is rising. 6 Also, few studies 2,4 have considered the influence of physical activity on associations between CRP and health outcomes. Conclusions-TheRegular physical activity is associated with lower CHD and diabetes risk. 7 Self-reported physical activity is inversely related with CRP concentrations. 8,9 Cardiorespiratory fitness ("fitness"), assessed with maximal exercise testing, is stronger than self-reported physical activity as a predictor of several health outcomes. 7,10 We showed higher fitness correlates with lower CHD risk factors. 11-13 Blair and associates observed lower cardiovascular mortality 14 and type 2 diabetes 15 rates with higher fitness, irrespective of obesity status. Data on fitness and health parameters are particularly sparse among women and minorities. 7,10,12,13 In the present study, we describe the cross-sectional association between fitness and CRP in a tri-ethnic sample of healthy women. MethodsInformed consent was obtained from 44 African American (AA), 45 Native American (NA), and 46 Caucasian (CA) women who volunteered to be in the Cross-Cultural Activity Participation Study (CAPS). The aim of CAPS was to develop physical activity surveys for diverse populations of women. 11,13,16,17 CAPS inclusion criteria were self-reported: AA, NA, or CA ethnicity, absence of symptomatic disease, and the absence of conditions tha...