Excess body weight is a major risk factor for cardiovascular disease, increasing the risk of hypertension, hyperglycaemia and dyslipidaemia, recognized as the metabolic syndrome. Adipose tissue acts as an endocrine organ by producing various signalling cytokines called adipokines (including leptin, free fatty acids, tumour necrosis factor-α, interleukin-6, C-reactive protein, angiotensinogen and adiponectin). A chronic dysregulation of certain adipokines can have deleterious effects on insulin signalling. Chronic sympathetic overactivity is also known to be present in central obesity, and recent findings demonstrate the consequence of an elevated sympathetic outflow to organs such as the heart, kidneys and blood vessels. Chronic sympathetic nervous system overactivity can also contribute to a further decline of insulin sensitivity, creating a vicious cycle that may contribute to the development of the metabolic syndrome and hypertension. The cause of this overactivity is not clear, but may be driven by certain adipokines. The purpose of this review is to summarize how obesity, notably central or visceral as observed in the metabolic syndrome, leads to adipokine expression contributing to changes in insulin sensitivity and overactivity of the sympathetic nervous system.

The purpose of this study was to examine the effects of a crossfit-based high-intensity power training (HIPT) program on aerobic fitness and body composition. Healthy subjects of both genders (23 men, 20 women) spanning all levels of aerobic fitness and body composition completed 10 weeks of HIPT consisting of lifts such as the squat, deadlift, clean, snatch, and overhead press performed as quickly as possible. Additionally, this crossfit-based HIPT program included skill work for the improvement of traditional Olympic lifts and selected gymnastic exercises. Body fat percentage was estimated using whole-body plethysmography, and maximal aerobic capacity (VO2max) was measured by analyzing expired gasses during a Bruce protocol maximal graded treadmill test. These variables were measured again after 10 weeks of training and compared for significant changes using a paired t-test. Results showed significant (p< 0.05) improvements of VO2max in men (43.10 ± 1.40 to 48.96 ± 1.42 ml · kg · min) and women (35.98 ± 1.60 to 40.22 ± 1.62 ml · kg · min) and decreased body fat percentage in men (22.2 ± 1.3 to 18.0 ± 1.3) and women (26.6 ± 2.0 to 23.2 ± 2.0). These improvements were significant across all levels of initial fitness. Significant correlations between absolute oxygen consumption and oxygen consumption relative to body weight was found in both men (r = 0.83, p < 0.001) and women (r = 0.94, p < 0.001), indicating that HIPT improved VO2max scaled to body weight independent of changes to body composition. Our data show that HIPT significantly improves VO2max and body composition in subjects of both genders across all levels of fitness.

Miner JA, Martini ER, Smith MM, Brunt VE, Kaplan PF, Halliwill JR, Minson CT. Short-term oral progesterone administration antagonizes the effect of transdermal estradiol on endotheliumdependent vasodilation in young healthy women. Am J Physiol Heart Circ Physiol 301: H1716 -H1722, 2011. First published August 19, 2011; doi:10.1152/ajpheart.00405.2011.-Very few studies have explored the cardiovascular effects of progesterone in premenopausal women. This study aimed to examine the short-term effects of oral progesterone alone, transdermal estrogen alone, and progesterone and estrogen combined on flow-mediated dilation (FMD) in healthy reproductive-aged women. We suppressed endogenous estrogens and progesterone in 17 premenopausal women for 10 -12 days using a gonadotropin-releasing hormone antagonist. On day 4 (hormone suppression condition), subjects were tested (n ϭ 17) and were then supplemented with either 200 mg micronized progesterone (n ϭ 8) orally or 0.1 mg estradiol (n ϭ 9) transdermally per day. On day 7 (progesterone-first or estradiol-first condition), subjects were tested and began supplementation with both hormones (n ϭ 17) and were tested again on day 10 (combined hormone condition). FMD of the brachial artery was assessed using B-mode arterial ultrasound, combined with synchronized Doppler analysis. As a result, significant differences in FMD were observed between hormone suppression (7.85 Ϯ 1.06%) and estrogen-first conditions (10.14 Ϯ 1.40%; P Ͻ 0.05). The estradiol-induced increase was abolished when oral progesterone was also supplemented (6.27 Ϯ 0.96%). In contrast, we observed a trend toward a decrease in FMD with unopposed progesterone administration, but no statistically significant differences were found between the progesterone-first (6.66 Ϯ 1.23%), hormone suppression (7.80 Ϯ 1.23%), and combined hormone conditions (7.40 Ϯ 1.29%). In conclusion, these data suggest that short-term oral micronized progesterone administration antagonizes the beneficial effect of transdermal estradiol on FMD.flow-mediated vasodilation; endothelial function; sex hormones; birth control WITH OVER 73% OF childbearing-aged women in the United States taking exogenous hormones for contraceptive and gynecological purposes (49a), the exploration of how exogenous hormones affect cardiovascular health is imperative. Although research on sex hormones has mainly focused on the effects of estrogens and manufactured progestins, there is relatively little known regarding the effect of progesterone on the vasculature. With progesterone production occurring naturally within the body and its bioidentical exogenous form being one of the most frequently prescribed progestogens, the need to understand the influence of progesterone on cardiovascular health is great.One of the primary methods used to investigate the effect of sex hormones on vascular health is via flow-mediated dilation (FMD). FMD, measured as the percent change in brachial artery diameter in response to an increase in shear stress, has been widely used as a nonin...

Background Few studies have examined how developing obesity in early adulthood affects the course of asthma. Objective We analyzed lung function and asthma impairment and risk among non-obese children with asthma, comparing those who were obese in young adulthood to those who remained non-obese. Methods Post-hoc analysis of 771 subjects with mild-moderate asthma who were not obese (pediatric definition, body mass index (BMI) <95th percentile) when enrolled in the Childhood Asthma Management Program at ages 5–12 years. Subjects were then followed to age ≥ 20 years. For visits at ages ≥ 20 years, spirometry values as percent predicted and recent asthma symptom scores and prednisone exposure were compared between 579 subjects who were non-obese at all visits and 151 who obese (adult definition of BMI ≥ 30 kg/m2) on at least one visit (median number of visits when obese = 4, IQR 2–7). Results Compared to participants who were non-obese (BMI 23.4 ± 2.6 kg/m2), those who became obese (BMI 31.5 ± 3.8 kg/m2) had significant decreases in FEV1/FVC (p<0.0003) and FEV1 (p = 0.001), without differences in FVC (p=0.15) during visits at ages ≥ 20 years. For each unit increase of BMI, FEV1 percent predicted decreased by 0.29 (p=0.0009). The relationship between BMI and lung function was not confounded by sex or BMI at baseline. Asthma impairment (symptom scores) and risk (prednisone use) did not differ between the two groups. Conclusion Becoming obese in early adulthood was associated with increased airway obstruction, without impact on asthma impairment or risk.

Objectives: Manual and physical therapists incorporate neurodynamic mobilisation (NDM) to improve function and decrease pain. Little is known about the mechanisms by which these interventions affect neural tissue. The objective of this research was to assess the effects of repetitive straight leg raise (SLR) NDM on the fluid dynamics within the fourth lumbar nerve root in unembalmed cadavers. Methods: A biomimetic solution (Toluidine Blue Stock 1% and Plasma) was injected intraneurally, deep to the epineurium, into the L4 nerve roots of seven unembalmed cadavers. The initial dye spread was allowed to stabilise and measured with a digital calliper. Once the initial longitudinal dye spread stabilised, an intervention strategy (repetitive SLR) was applied incorporating NDMs (stretch/relax cycles) at a rate of 30 repetitions per minute for 5 minutes. Post-intervention calliper measurements of the longitudinal dye spread were measured. Results: The mean experimental posttest longitudinal dye spread measurement (1.1 ± 0.9 mm) was significantly greater (P = 0.02) than the initial stabilised pretest longitudinal dye spread measurement. Increases ranged from 0.0 to 2.6 mm and represented an average of 7.9% and up to an 18.1% increase in longitudinal dye spread. Discussion: Passive NDM in the form of repetitive SLR induced a significant increase in longitudinal fluid dispersion in the L4 nerve root of human cadaveric specimen. Lower limb NDM may be beneficial in promoting nerve function by limiting or altering intraneural fluid accumulation within the nerve root, thus preventing the adverse effects of intraneural oedema.