Time spent in sedentary posture is associated with waist circumference and cardiovascular risk

Background The relationship between metabolic risk and time spent sitting, standing and stepping has not been well established. The present study aimed to determine associations of objectively measured time spent siting, standing and stepping, with coronary heart disease (CHD) risk. Methods A cross-sectional study of healthy non-smoking Glasgow postal workers, n=111 (55 office-workers, 5 women, and 56 walking/delivery-workers, 10 women), who wore activPAL physical activity monitors for seven days. Cardiovascular risks were assessed by metabolic syndrome categorisation and 10-y PROCAM risk. Results Mean(SD) age was 40(8) years, BMI 26.9(3.9)kg/m-2 and waist circumference 95.4(11.9)cm. Mean(SD) HDL-cholesterol 1.33(0.31), LDL-cholesterol 3.11(0.87), triglycerides 1.23(0.64)mmol/l and 10-y PROCAM risk 1.8(1.7)%. Participants spent mean(SD) 9.1(1.8)h/d sedentary, 7.6(1.2)h/d sleeping, 3.9(1.1)h/d standing and 3.3(0.9)h/d stepping, accumulating 14,708(4,984)steps/d in 61(25) sit-to-stand transitions per day. In univariate regressions - adjusting for age, sex, family history of CHD, shift worked, job type and socio-economic status - waist circumference (p=0.005), fasting triglycerides (p=0.002), HDL-cholesterol (p=0.001) and PROCAM-risk (p=0.047) were detrimentally associated with sedentary time. These associations remained significant after further adjustment for sleep, standing and stepping in stepwise regression models. However, after further adjustment for waist circumference, the associations were not significant. Compared to those without the metabolic syndrome, participants with the metabolic syndrome were significantly less active – fewer steps, shorter stepping duration and longer time sitting. Those with no metabolic syndrome features walked >15,000 steps/day, or spent >7h/day upright. Conclusion Longer time spent in sedentary posture is significantly associated with higher CHD risk and larger waist circumference

Effects Of Stimulator Substances On Aerobic Methyl tert-Butyl Ether Biodegradation By Microbial Consortium

In this study dissolved humic substances and yeast extract were tested in different concentrations for enhancing methyl tert-butyl ether mineralization by isolated microorganisms from a variety of sources. All experiments were conducted at a constant temperature of 25ºC. Vials of 50 mL and 125 mL volume sealed with Teflon-lined Mini-Nert caps was used for microcosm experiments. In all experiments 1% sodium azide were used as control. Samples of bacterial cultures that metabolize methyl tert-butyl ether have been analysed by direct GC analysis using flame ionization detector. Cultures able to metabolize have been found in activated sludge and soils. These microorganisms were gram-positive bacterium. An aerobic microbial consortium was enriched in laboratory for four months. Methyl tert-butyl ether has been shown to biodegrade under aerobic and co-metabolic conditions. A microbial consortium isolated from activated sludges was identified as Cocobacillus. The concentration of the initial attached biomass was about 0.11 g/L of dry weight. The maximum mineralization rate and beneficial effects of stimulator substances on aerobic biodegradation of methyl tert-butyl ether occurred with the culture by combined concentrations of 500 mg/L of yeast extract and 20 mg/L of peat humic growth support of microbial consortium within 216 h and in presence of high oxygen levels and well mixing conditions. It was shown that adding, peat humic and yeast extract together, had better stimulatory effect on methyl tert-butyl ether biodegradation. Results clearly showed a stimulatory effect on methyl tert-butyl ether consumption higher than 20%. Consortium was capable of degrading concentrations of ≤1000 mg/L, whereas concentrations of >1000 mg/L, were not degraded

The Effects of Alpha-Glycerylphosphorylcholine on Heart Rate Variability and Hemodynamic Variables Following Sprint Interval Exercise in Overweight and Obese Women

The current study examined the effects of Alpha-Glycerylphosphorylcholine (A-GPC) on heart rate variability (HRV) and hemodynamic responses following a sprint interval exercise (SIE) in women who were overweight or obese. Participants (n = 12, 31.0 ± 4.6 years; 29.4 ± 2.1 kg/m2) consumed 1000 mg of A-GPC or a placebo after eating breakfast in a randomized, double-blind cross-over design. After 60 min, participants performed two bouts of the SIE (30 s Wingate) interspersed with 4 min of active recovery (40 rpm). Hemodynamic variables and HRV domains were measured before and 60 min after the A-GPC consumption, immediately after SIE, and every 15 min up to 120 min during recovery. A-GPC consumption increased resting levels of both the time domain (Standard Deviation of RR wave intervals [SDNN] and percentage of interval differences of adjacent RR intervals greater than 50 ms [pNN50%]) and frequency domain (high frequency [HF] and low frequency [LF]) variables of HRV (p p p p < 0.05) faster in the A-GPC compared to the placebo session. We concluded that A-GPC consumption recovers HRV and blood pressure faster following strenuous exercise in overweight and obese women, and that it might favorably modify cardiac autonomic function

Short-Duration High-Intensity Interval Exercise Training Is More Effective Than Long Duration for Blood Pressure and Arterial Stiffness but Not for Inflammatory Markers and Lipid Profiles in Patients with Stage 1 Hypertension

Purpose: The present study compared the effects of 2 different high-intensity interval training (HIIT) protocols on arterial stiffness, lipid profiles, and inflammatory markers in hypertensive patients. Methods: Thirty hypertensive (stage 1) patients, aged 48.0 ± 3.2 yr, were randomly allocated to the short-duration HIIT (SDHIIT, n = 10), long-duration HIIT (LDHIIT, n = 10), and control (n = 10) groups. After a 2-wk preparatory phase of continuous mild training, patients in the SDHIIT group performed 8 wk of HIIT including 27 repetitions of 30-sec activity at 80 to 100 of o2peak interspersed with 30-sec passive/active (10-20 of o2peak) recovery. Patients in the LDHIIT group performed 8 wk of HIIT, 32 min/session including 4 repetitions of 4-min activity at 75 to 90 of o2peak interspersed with 4-min passive/active (15-30 of o2peak) recovery. Blood pressure (BP), pulse wave velocity (PWV), inflammatory markers, and lipid profiles were measured before and after training. Results: Significant (P &lt;.05) reductions in systolic blood pressure and PWV were found following 2 training protocols, though, only the changes in PWV following the SDHIIT were significantly different than those in the LDHIIT and control groups. Interleukin-6 and triglycerides decreased and interleukin-10 increased significantly (P &lt;.01) following both HIIT programs, whereas the differences between the 2 training protocols were not statistically significant. C-reactive protein and lipids did not change significantly following HIIT. Conclusions: Performing HIIT improves systolic blood pressure and inflammatory markers in patients with stage 1 hypertension irrespective of the HIIT intensity and duration, and PWV improvement is intensity related. Copyright © 2019 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited