The Phillips et al. (2013) cut-points for the GENEActiv accelerometer can be used in children aged 5-8 years old to distinguish sedentary behaviour, moderate and vigorous PA behaviour. What is Known: • Accelerometers are fast becoming the most widely used measure of physical activity in public health research. • The GENEActive wrist worn accelerometer has been validated for use with children aged 8 years and older What is New: • The GENEActive wrist worn accelerometer can be used to assess physical activity in children aged 5-8 years old. • Previously established cut-points for the GENEActiv accelerometer can be used in children aged 5-8 years old to distinguish sedentary behaviour, moderate and vigorous PA behaviour.

This study evaluated the effects of ingesting sodium bicarbonate (NaHCO3) or caffeine individually or in combination on high-intensity cycling capacity. In a counterbalanced, crossover design, 13 healthy, noncycling trained males (age: 21 ± 3 years, height: 178 ± 6 cm, body mass: 76 ± 12 kg, peak power output (Wpeak): 230 ± 34 W, peak oxygen uptake: 46 ± 8 mL·kg(-1)·min(-1)) performed a graded incremental exercise test, 2 familiarisation trials, and 4 experimental trials. Trials consisted of cycling to volitional exhaustion at 100% Wpeak (TLIM) 60 min after ingesting a solution containing either (i) 0.3 g·kg(-1) body mass sodium bicarbonate (BIC), (ii) 5 mg·kg(-1) body mass caffeine plus 0.1 g·kg(-1) body mass sodium chloride (CAF), (iii) 0.3 g·kg(-1) body mass sodium bicarbonate plus 5 mg·kg(-1) body mass caffeine (BIC-CAF), or (iv) 0.1 g·kg(-1) body mass sodium chloride (PLA). Experimental solutions were administered double-blind. Pre-exercise, at the end of exercise, and 5-min postexercise blood pH, base excess, and bicarbonate ion concentration ([HCO3(-)]) were significantly elevated for BIC and BIC-CAF compared with CAF and PLA. TLIM (median; interquartile range) was significantly greater for CAF (399; 350-415 s; P = 0.039; r = 0.6) and BIC-CAF (367; 333-402 s; P = 0.028; r = 0.6) compared with BIC (313: 284-448 s) although not compared with PLA (358; 290-433 s; P = 0.249, r = 0.3 and P = 0.099 and r = 0.5, respectively). There were no differences between PLA and BIC (P = 0.196; r = 0.4) or between CAF and BIC-CAF (P = 0.753; r = 0.1). Relatively large inter- and intra-individual variation was observed when comparing treatments and therefore an individual approach to supplementation appears warranted

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The muscles of the human airway are innervated by a variety of cranial nerves, refl ecting the varied functions of the airway. This raises the question: to what extent is respiratory motor control similar in muscles controlled by different cranial nerves? In addressing this question three features of airway muscles will be evaluated: the presence of preinspiratory activation; the range of different motor unit discharge patterns identifi ed in muscles; and the effect of sleep onset. Inspiratory Sleep, Science and Research A2Introduction: Apnoea is defi ned as cessation of breathing with implicit pathophysiology. For preterm infants apnoea defi nitions are not Invited speakersThe Divided Attention Steering Simulator (DASS) developed in the UK and the AusEd driving simulator developed jointly by UK and Australian investigators are simple relatively inexpensive computer based simulators able to acquire steering and speed deviation, divided attention, braking reaction and crash data at 10 Hz and 30 Hz respectively. The INRETS and the OKTAL simulator developed in France are more advanced with real car interior controls to manoeuvre the vehicle. They use large high defi nition display (3D for the OKTAL) and collect more comprehensive data from fuel consumption to steering, braking and crashes. On-road vehicles equipped with dual controls and video cameras able to detect lane position have now been used by French sleep researchers. The use of professional driving instructors to assess driving performance during on-road driving has also been used in Australia.When simple simulators such as the DASS have been compared to real driving, simulator performance measures correlate with on-road performance (relative validity) but tend to overestimate and magnify performance impairments relative to real driving. Higher fi delity simulators are found to more precisely represent real driving approaching "absolute validity". The use of driving simulators and on-road driving experiments in patients with OSA reveal that regardless of which driving assessment tool is used, OSA patients' consistently show significantly worse performance compared to non-OSA subjects, often with large effect sizes.Basic and more advanced driving simulators are useful to detect driving performance impairment in OSA patients particularly in simple experimental designs. With further development of high fi delity validated driving simulators, these tools should become more accessible and provide more reliable information on driving performance in OSA and other populations at risk of MVAs and allow for more complicated and realistic experimental designs.

Background: The ability to objectively assess physical activity and inactivity in free living individuals is important in understanding activity patterns and the dose response relationship with health. Currently, a large number of research tools exist, but little evidence has examined the validity/utility of the Research Tracker 6 (RT6) monitor. Questions remain in regard to the best placements, positions, and cut-points in young adults to determine activity intensity across a range of activities. This study sought to address this gap in young adults. The study aims were 1) to examine criterion validity of RT6 in comparison to breath-by-breath gas analysis; 2) convergent validity of RT6 in comparison to ActiGraph and GENEActiv; 3) development of RT6 tri-axial vector magnitude cut-points to classify physical activity at different intensities (i.e., for sedentary, moderate, and vigorous); 4) to compare the generated cut-points of the RT6 in comparison to other tools. Methods: Following ethics approval and informed consent, 31 young adults (age = 22±3 years: BMI = 23±3 kg/m2) undertook five modes of physical activity/sedentary behaviors while wearing three different accelerometers at hip and wrist locations (ActiGraph GT9X Link, GENEActiv, RT6). Expired gas was sampled during the five activities (MetaMax 3B). Correlational analysis assessed the relationship between accelerometer devices and METs/VO2. Receiver Operating Characteristic Curves analysis were used to calculate area under the curve and define cut-points for physical activity intensities. Results: The RT6 demonstrated criterion and convergent validity (r = 0.662–0.966, P < .05). RT6 generally performed good to excellent across activity intensities and monitor position (sedentary [AUC = 0.862–0.911], moderate [AUC = 0.849–0.830], vigorous [AUC = 0.872–0.877]) for non-dominant and dominant position, respectively. Cut-points were derived across activity intensities for non-dominant- and dominant-worn RT6 devices. Comparison of the RT6 derived cut-points identified appropriate agreement with comparative tools but yields the strongest agreement with the ActiGraph monitor at the hip location during sedentary, light, and moderate activity. Conclusion: The RT6 performed similar to the ActiGraph and GENEActiv and is capable of classifying the intensity of physical activity in young adults. As such this may offer a more useable tool for understanding current physical activity levels and in intervention studies to monitor and track changes without the excessive need for downloading and making complex analysis, especially given the option to view energy expenditure data while wearing it. The RT6 should be placed on the dominant hip when determining activities that are sedentary, moderate, or vigorous intensity.