An investigation of temperature-sensing textiles for temperature monitoring during sub-maximal cycling trials

Temperature sensing textiles have been proposed for a variety of applications including health monitoring and sports. Skin temperature (Tsk) measurements are an important parameter in performance sports and can be used to better understand thermoregulation during exercise. Currently, most Tsk measurements are taken using skin mounted thermistors, which can be uncomfortable to the wearer, or thermal imaging, which can be difficult to implement and analyse. This work investigates the feasibility of using textile temperature sensing electronic yarns (E-yarns) to measure human skin temperature during sub maximal cycling trials. E-yarns were attached to commercially available cycling suits and measurements were recorded using both the E-yarns and the skin mounted thermistors at rest and during sub maximal cycling. Temperature readings were compared between the two temperature sensing methodologies to determine the viability of using the temperature sensing E-yarns for this application. Differences in the Tsk measurements as high as 5.9 °C between the E-yarns and skin mounted thermistors for participants at rest have been shown. This work has also identified that a build-up of sweat significantly altered the Tsk recorded by the E-yarns in some cases. Further experiments explored the effect of saline solutions (simulating sweat) on the response of the temperature sensing E-yarns. This work has highlighted boundary conditions for taking point Tsk measurement using electronic textiles

Group studio cycling; an effective intervention to improve cardio-metabolic health in overweight physically inactive individuals

Introduction: Supervised, laboratory based studies of high intensity interval training (HIIT) is effective at improving health markers in groups at risk of cardiovascular and metabolic disease. Studio cycling, incorporating aerobic and high intensity exercise, may offer a platform for the implementation of HIIT within the wider community. Methods: Eight, overweight, physically inactive (<1.5 hr·wk-1) but otherwise healthy volunteers completed eight weeks of supervised studio cycling lasting 20-50 minutes 3 times per week. Participants underwent assessment for maximal oxygen uptake (VO2max) body composition, blood lipids, glucose tolerance and insulin resistance before and after the intervention. Results: Adherence to training was >95%. Mean and peak intensity were equivalent to 83% and 97% of HRmax·VO2max increased from 27.1 ± 4.7 mL·kg·min-1 to 30.3 ± 4.3 mL·kg·min-1 (p < 0.0001). Body fat percentage was reduced by 13.6% from 31.8 ± 2.4% to 27.5 ± 4.5% (p < 0.05). Total cholesterol (4.8 ± 1.1 mmol·L-1 to 4.2 ± 1.2 mmol·L-1) and low-density lipoprotein cholesterol (2.6 ± 0.9 mmol·L-1 to 2.0 ± 1.2 mmol·L-1) were reduced (both p < 0.05). There were no significant differences to glucose tolerance or insulin resistance. Discussion: Group exercise is effective at improving the cardio-metabolic health in previously physically inactive overweight individuals. Coupled with the high adherence rate, studio cycling offers an effective intervention improving cardiovascular health in physically inactive cohorts. Conclusions: Studio cycling can be implemented as a highly effective high intensity interval training intervention for improving health in overweight, inactive individuals and may promote improved exercise adherence

Lower volume throughout the taper and higher intensity in the last interval session prior to a 1,500 m time trial improves performance

Eight highly-trained middle-distance runners (1,500 m personal best 4:01.4 ± 0:09.2 min) completed two 7-day tapers, separated by at least 3 weeks of regular training: (i) prescribed using prediction models from elite middle-distance runners, where continuous running volume was reduced by 30% and interval intensity was equal to 1,500 m race pace (RP); and (ii) continuous running volume was reduced by 60% and intensity of the final interval session was completed at 110% of 1,500 m race pace (HI). Performance was assessed using 1,500 m time trials on an indoor 200 m track one day before, and one day after each taper. Performance time was improved after HI by 5.2 ± 3.7 s (mean ± 90% confidence limits, p = 0.03) and by 3.2 ± 3.8 s after RP (p = 0.15). The first and second 300-m segments of the 1,500 m time trial were faster post-taper in RP (p = 0.012 and p = 0.017, respectively) and HI (both p = 0.012). Running faster than race pace late in a low-volume taper is recommended to improve 1,500 m track performance. A positive pacing strategy is adopted after tapering, although care should be taken to avoid an over-fast start. Novel Findings: A large reduction in volume during tapering and an increase in final interval session intensity improves running performance. Athletes adopt a negative pacing strategy before tapering and a positive-pacing strategy after tapering

Passive heating and glycaemic control in non-diabetic and diabetic individuals: a systematic review and meta-analysis

Objective: Passive heating (PH) has begun to gain research attention as an alternative therapy for cardio-metabolic diseases. Whether PH improves glycaemic control in diabetic and non-diabetic individuals is unknown. This study aims to review and conduct a meta-analysis of published literature relating to PH and glycaemic control. Methods: Electronic data sources, PubMed, Embase and Web of Science from inception to July 2018 were searched for randomised controlled trials (RCT) studying the effect of PH on glycaemic control in diabetic or non-diabetic individuals. To measure the treatment effect, standardised mean differences (SMD) with 95 % confidence intervals (CI) were calculated. Results: Fourteen articles were included in the meta-analysis. Following a glucose load, glucose concentration was greater during PH in non-diabetic (SMD 0.75, 95 % CI 1.02 to 0.48, P 0.050) and a glucose challenge given within 24 hours post-heating (SMD 0.30, 95 % CI 0.62 to -0.02, P > 0.050). Conclusion: PH preceded by a glucose load results in acute glucose intolerance in non-diabetic and diabetic individuals. However, heating a non-diabetic individual without a glucose load appears not to affect glycaemic control. Likewise, a glucose challenge given within 24 hours of a single-bout of heating does not affect glucose tolerance in non-diabetic individuals. Despite the promise PH may hold, no short-term benefit to glucose tolerance is observed in non-diabetic individuals. More research is needed to elucidate whether this alternative therapy benefits diabetic individuals

The effects of an increase in intensity during tapering on 1,500m running performance

We examined the effect of completing the final interval training session during a taper at either: i) race pace; or ii) faster than race pace, on 1,500 m running performance and neuromuscular performance. Ten trained runners (age 21.7 ± 3.0 years, height 182.9 ± 7.0 cm, body mass 73.4 ± 6.8 kg, personal best 1,500 m time 4:17.5 ± 0:26.9 min) completed two conditions, consisting of 7-d of regular training and a 7-d taper, separated by three weeks of training. In one condition, the taper was prescribed using prediction models based on the practices of elite British middle-distance runners, with the intensity of the final interval session being equal to 1,500 m race pace (RP). The taper was repeated in the HI condition, except the final interval session was completed at 115% of 1,500 m race pace. A 1,500 m treadmill time trial, measures of maximum voluntary isometric strength (MVC) and rate of force development (RFD) were completed before and after regular training and tapering. Performance was most likely improved after RP (mean ± 90% confidence limits, 10.1 ± 1.6 s), and possibly beneficial after HI (4.2 ± 12.0 s). Both MVC force (p = 0.002) and RFD (p = 0.02) were improved after tapering, without differences between conditions. A race-pace taper based on the practices of elite middle-distance runners is recommended to improve performance in young, sub-elite runners. The effect of this strategy with an increase in interval intensity is highly variable and should be implemented with caution

Mode shifting in school travel mode: examining the prevalence and correlates of active school transport in Ontario, Canada

<p>Abstract</p> <p>Background</p> <p>Studies examining the correlates of school transport commonly fail to make the distinction between morning and afternoon school trips. The purpose of this study was to examine the prevalence and correlates of mode shift from passive in the morning to active in the afternoon among elementary and secondary school students in Ontario, Canada.</p> <p>Methods</p> <p>Data were derived from the 2009 cycle of the Ontario Student Drug Use and Health Survey (OSDUHS). 3,633 students in grades 7 through 12 completed self-administered questionnaires. Socio-demographic, behavioural, psychological, and environmental predictors of active school transport (AST) were assessed using logistic regression.</p> <p>Results</p> <p>Overall, 47% and 38% of elementary school students reported AST to and from school, respectively. The corresponding figures were 23% and 32% for secondary school students. The prevalence of AST varied temporarily and spatially. There was a higher prevalence of walking/biking found for elementary school students than for secondary school students, and there was an approximate 10% increase in AST in the afternoon. Different correlates of active school transport were also found across elementary and secondary school students. For all ages, students living in urban areas, with a shorter travel time between home and school, and having some input to the decision making process, were more likely to walk to and from school.</p> <p>Conclusions</p> <p>Future research examining AST should continue to make the analytic distinction between the morning and afternoon trip, and control for the moderating effect of age and geography in predicting mode choice. In terms of practice, these variations highlight the need for school-specific travel plans rather than 'one size fits all' interventions in promoting active school transport.</p

Effects of sex, age, and visits on receipt of preventive healthcare services: a secondary analysis of national data

BACKGROUND: Sex and age may exert a combined influence on receipt of preventive services with differences due to number of ambulatory care visits. METHODS: We used nationally representative data to determine weighted percentages and adjusted odds ratios of men and women stratified by age group who received selected preventive services. The presence of interaction between sex and age group was tested using adjusted models and retested after adding number of visits. RESULTS: Men were less likely than women to have received blood pressure screening (aOR 0.44;0.40–0.50), cholesterol screening (aOR 0.72;0.65–0.79), tobacco cessation counseling (aOR 0.66;0.55–0.78), and checkups (aOR 0.53;0.49–0.57). In younger age groups, men were particularly less likely than women to have received these services. In adjusted models, this observed interaction between sex and age group persisted only for blood pressure measurement (p = .016) and routine checkups (p < .001). When adjusting for number of visits, the interaction of age on receipt of blood pressure checks was mitigated but men were still overall less likely to receive the service. CONCLUSION: Men are significantly less likely than women to receive certain preventive services, and younger men even more so. Some of this discrepancy is secondary to a difference in number of ambulatory care visits

Theory of disk accretion onto supermassive black holes

Accretion onto supermassive black holes produces both the dramatic phenomena associated with active galactic nuclei and the underwhelming displays seen in the Galactic Center and most other nearby galaxies. I review selected aspects of the current theoretical understanding of black hole accretion, emphasizing the role of magnetohydrodynamic turbulence and gravitational instabilities in driving the actual accretion and the importance of the efficacy of cooling in determining the structure and observational appearance of the accretion flow. Ongoing investigations into the dynamics of the plunging region, the origin of variability in the accretion process, and the evolution of warped, twisted, or eccentric disks are summarized.Comment: Mostly introductory review, to appear in "Supermassive black holes in the distant Universe", ed. A.J. Barger, Kluwer Academic Publishers, in pres

The Evolution of Compact Binary Star Systems

We review the formation and evolution of compact binary stars consisting of white dwarfs (WDs), neutron stars (NSs), and black holes (BHs). Binary NSs and BHs are thought to be the primary astrophysical sources of gravitational waves (GWs) within the frequency band of ground-based detectors, while compact binaries of WDs are important sources of GWs at lower frequencies to be covered by space interferometers (LISA). Major uncertainties in the current understanding of properties of NSs and BHs most relevant to the GW studies are discussed, including the treatment of the natal kicks which compact stellar remnants acquire during the core collapse of massive stars and the common envelope phase of binary evolution. We discuss the coalescence rates of binary NSs and BHs and prospects for their detections, the formation and evolution of binary WDs and their observational manifestations. Special attention is given to AM CVn-stars -- compact binaries in which the Roche lobe is filled by another WD or a low-mass partially degenerate helium-star, as these stars are thought to be the best LISA verification binary GW sources.Comment: 105 pages, 18 figure