Interrupting Sitting Time with Simple Resistance Activities Lowers Postprandial Insulinemia in Adults with Overweight or Obesity.

OBJECTIVE: This study aimed to examine the effects on postprandial glucose and insulin responses of interrupting sitting time with brief bouts of simple resistance activities (SRAs) in adults with overweight or obesity. METHODS: Participants (n = 19) were recruited for a randomized crossover trial involving the following two 6-hour conditions: (1) uninterrupted sitting or (2) sitting with 3-minute bouts of SRAs (half-squats, calf raises, gluteal contractions, and knee raises) every 30 minutes (total duration = 27 minutes). Incremental areas under the curve (iAUC) for glucose, insulin, and insulin:glucose ratio were analyzed as prespecified secondary outcomes using mixed-effects log-linear regression adjusted for sex, BMI, treatment order, and preprandial values. Results are reported as multiplicative change (exponentiated coefficient [EC] with 95% CI) relative to the control condition. RESULTS: Glucose iAUC during the SRA condition was not significantly different from the prolonged sitting condition (EC = 0.92; 95% CI: 0.73-1.16; P = 0.43). However, SRAs lowered the postprandial insulin response by 26% (EC = 0.74; 95% CI: 0.64-0.85; P < 0.001), and there was a 23% lowering of the iAUC for insulin:glucose (EC = 0.77; 95% CI: 0.67-0.89; P < 0.001). CONCLUSIONS: In adults with overweight or obesity, frequent interruptions to sitting time with SRAs lowered postprandial insulin responses and insulin:glucose. These findings may have implications for mitigating cardiometabolic risk in adults with overweight or obesity who engage in prolonged periods of sitting.

Acute effects of active breaks during prolonged sitting on subcutaneous adipose tissue gene expression: an ancillary analysis of a randomised controlled trial.

Active breaks in prolonged sitting has beneficial impacts on cardiometabolic risk biomarkers. The molecular mechanisms include regulation of skeletal muscle gene and protein expression controlling metabolic, inflammatory and cell development pathways. An active communication network exists between adipose and muscle tissue, but the effect of active breaks in prolonged sitting on adipose tissue have not been investigated. This study characterized the acute transcriptional events induced in adipose tissue by regular active breaks during prolonged sitting. We studied 8 overweight/obese adults participating in an acute randomized three-intervention crossover trial. Interventions were performed in the postprandial state and included: (i) prolonged uninterrupted sitting; or prolonged sitting interrupted with 2-minute bouts of (ii) light- or (iii) moderate-intensity treadmill walking every 20 minutes. Subcutaneous adipose tissue biopsies were obtained after each condition. Microarrays identified 36 differentially expressed genes between the three conditions (fold change ≥0.5 in either direction; p < 0.05). Pathway analysis indicated that breaking up of prolonged sitting led to differential regulation of adipose tissue metabolic networks and inflammatory pathways, increased insulin signaling, modulation of adipocyte cell cycle, and facilitated cross-talk between adipose tissue and other organs. This study provides preliminary insight into the adipose tissue regulatory systems that may contribute to the physiological effects of interrupting prolonged sitting.

Television Viewing Time and Inflammatory-Related Mortality.

PURPOSE: Television (TV) viewing time is associated with increased risk of all-cause, cardiovascular and cancer mortality. Although TV time is detrimentally associated with key inflammatory markers, the associations of TV time with other inflammatory-related mortality (with a predominant inflammatory, oxidative or infectious component, but not attributable to cancer or cardiovascular causes), are unknown. METHODS: Among 8933 Australian adults (4593 never-smokers) from the baseline (1999-2000) Australian Diabetes, Obesity and Lifestyle Study (median follow-up, 13.6 yr), we examined TV time in relation to noninflammatory and inflammatory-related mortality (not attributable to cancer or cardiovascular causes, hereafter "inflammatory-related" mortality). Because smoking has a significant inflammatory component, we also examined this relationship in never-smokers. RESULTS: Of 896 deaths, 248 were attributable to cardiovascular disease, 346 to cancer, 130 to other inflammatory-related causes (71 for never-smokers), and 172 to noninflammatory-related causes (87 for never-smokers). After multivariate adjustment for age, sex, education, household income, smoking status, alcohol intake, energy intake, diet, and cardiometabolic risk biomarkers (model 3), every additional hours per day of TV time was associated with increased risk of inflammatory-related mortality in the overall population (hazard ratio, 1.12; 95% confidence interval, 1.00-1.25) and in never-smokers (1.18; 1.00, 1.40). These results were attenuated after additional adjustment for leisure-time physical activity. After multivariate adjustment (model 3), no association was observed for noninflammatory mortality in the overall population (0.95; 0.85, 1.07), but risk tended to decrease for never-smokers (0.85; 0.75, 1.02). CONCLUSIONS: In summary, before adjustment for leisure-time physical activity, TV time was associated with increased risk of inflammatory-related mortality. This is consistent with the hypothesis that high TV viewing may be associated with a chronic inflammatory state.

Does the type of activity "break" from prolonged sitting differentially impact on postprandial blood glucose reductions? An exploratory analysis.

Frequent breaks in prolonged sitting are associated beneficially with glycaemic control. However, the contribution of energy expenditure to this relationship has not been well characterised. In this exploratory analysis, data from 3 laboratory trials that standardised test meals, cohort characteristics (overweight/obese, sedentary), and break frequency and duration were pooled. Higher energy expenditures of different types of breaks (standing, light- or moderate-intensity walking) were associated with lower postprandial glucose and insulin responses in a dose-dependent manner.

Joint associations of smoking and television viewing time on cancer and cardiovascular disease mortality.

Excessive sitting time and smoking are pro-inflammatory lifestyle factors that are associated with both cancer and cardiovascular disease (CVD) mortality. However, their joint associations have not been investigated. We examined the associations of television (TV) viewing time with cancer and CVD mortality, according to smoking status, among 7,498 non-smokers (34% ex-smokers) and 1,409 current-smokers in the Australian Diabetes, Obesity and Lifestyle Study. During 117,506 person-years (median 13.6 years) of follow-up, there were 346 cancer and 209 CVD-related deaths. Including an interaction between TV time and smoking status in the model significantly improved the goodness of fit for cancer (p = 0.01) but not CVD mortality (p = 0.053). In the multivariate-adjusted model, every additional hr/d of TV time was associated with increased risk of cancer-related (HR 1.23; 95% CI 1.08-1.40), but not CVD-related mortality (HR 1.16; 95% CI 0.97-1.38) in current-smokers. Elevated multivariate-adjusted cancer mortality HRs were observed for current-smokers watching 2 to <4 hr/d (HR 1.45; 95% CI 0.78-2.71) and ≥4 hr/d (HR 2.26; 95% CI 1.10-4.64), compared to those watching <2 hr/d. Current-smokers watching 2 to <4 hr/d (HR 1.07; 95% CI 0.45-2.53) and ≥4 hr/d (HR 1.92; 95% CI 0.76-4.84) did not have a significantly higher risk of CVD mortality, compared to <2 hr/d. No associations were observed for non-smokers. These findings show an association of TV, a common sedentary behavior, with cancer mortality in current-smokers. The association with CVD mortality was less clear. Further exploration in larger data sets is warranted. Limiting TV viewing time may be of benefit in reducing cancer mortality risk in current-smokers.

Electromyographic (EMG) neuromonitoring in otolaryngology-head and neck surgery.

Intraoperative neuromonitoring (IONM) is a relatively recent advance in electromyography (EMG) applied to otolaryngology-head and neck surgery. Its purpose is to allow real-time identification and functional assessment of vulnerable nerves during surgery. The nerves most often monitored in head and neck surgery are the motor branch of the facial nerve (VII), the recurrent or inferior laryngeal nerves (X), the vagus nerve (X), and the spinal accessory nerve (XI), with other cranial lower nerves monitored less frequently. Morbidity from trauma to these nerves is significant and obvious, such as unilateral facial paresis. Although functional restorative surgery is usually considered to repair the effects of such an insult, the importance of preventing nerve injury in head and neck surgery is obvious. This article focuses on the anesthetic considerations pertinent to IONM of peripheral cranial nerves during otolaryngologic-head and neck surgery. The specific modality of IONM is EMG, both spontaneous and evoked.

Anesthesia issues in the perioperative management of myasthenia gravis.

Myasthenia gravis (MG) is an autoimmune disease of the neuromuscular junction. Current anesthetic practice may require the use of neuromuscular blocking (NMB) drugs that act at this junction to facilitate control of the airway and allow procedures to be performed on a motionless MG patient. This competes with the goals of rapid emergence and recapture of preoperative muscle strength following anesthesia. In particular, avoiding prolonged periods of postoperative mechanical ventilation is a paramount concern of patients, families, and physicians. Standard anesthetic agents and, if needed, judiciously titrated NMB drugs generally allow safe emergence and immediate extubation for most low-risk MG patients. If necessary, postoperative mechanical ventilation is accomplished with the use of specialized monitoring devices that help monitor awareness and depth of sedation. Currently used intravenous sedatives allow titrated depth of sedation and rapid emergence when extubation is appropriate. Communication to the patient, family, and other caregivers of the goals of the anesthetic plan and of the patient's evolving status are also very important duties of the anesthesiologist.