Objective:Type 2 diabetes is associated with impaired respiratory and cardiovascular control. Physical exercise training is a well-established tool in the treatment of diabetes. However, effects of short-term exercise training on respiratory control in diabetes are unknown. Thus, we examined the effects of 4 weeks of exercise training (high intensity interval-and continuous moderate exercise training; HIT and CMT) on cardiorespiratory control and aerobic capacity in type 2 diabetes subjects. Methods: Fifteen non-insulin dependent subjects with type 2 diabetes (4 female, 11 male, age 59.6 ± 1.5 years, BMI 29.5 ± 1.0 kg/m 2 , HbA1C 7.0 ± 0.3%) were randomized to either supervised HIT (N=8) or CMT (N= 7), both equalized for the total amount of work, for 3 times a week over 4 weeks. At baseline and follow up, measurements of hypercapnic and hypoxic ventilatory response (HCVR; HVR), Baroreflex Sensitivity (BRS) and VO 2 peak were performed. Results: Four weeks of supervised exercise training increased resting HCVR (from 0.55 ± 0.1 to 0.73 ± 0.1 L/ min/mmHgCO 2-et), whereas HVR and BRS remained unchanged. VO 2 peak (27.5 ± 1.4 versus 30.1 ± 1.6 ml/kg/min) and VO 2 at anaerobic threshold (19.7 ± 1.0 versus 21.9 ± 1.3 ml/kg/min) increased in the whole group. No significant changes between HIT and CMT were observed, except a slight increase in haemoglobin concentration after HIT. Conclusion: Our findings indicate that short-term exercise training increases HCVR associated with an improvement in aerobic capacity in patients with type 2 diabetes. HIT might demonstrate a less time demanding alternative to CMT. These findings are of clinical relevance, as exercise capacity predicts cardiovascular and overall mortality. J ou rna l o f D ia be tes & M e ta bolism

Introduction.A lack of knowledge among laypersons about the hazards of high-altitude exposure contributes to morbidity and mortality from acute mountain sickness (AMS), high altitude cerebral edema (HACE), and high altitude pulmonary edema (HAPE) among high altitude travelers. There are guidelines regarding the recognition, prevention, and treatment of acute altitude illness for experts, but essential knowledge for laypersons traveling to high altitudes has not been defined. We sought expert consensus on the essential knowledge required for people planning to travel to high altitudes. Methods:The Delphi method was used. The panel consisted of two moderators: a core expert group and a plenary expert group. The moderators made a preliminary list of statements defining the desired minimum knowledge for laypersons traveling to high altitudes, based on the relevant literature. These preliminary statements were then reviewed, supplemented, and modified by a core expert group. A list of 33 statements was then presented to a plenary group of experts in successive rounds.Results: It took 3 rounds to reach a consensus. Of the 10 core experts invited, seven completed all the rounds. Of the 76 plenary experts, 41 (54%) participated in round 1, and of these 41 a total of 32 (78%) experts completed all three rounds. The final list contained 28 statements in five categories (altitude physiology, sleeping at altitude, AMS, HACE, and HAPE). This list represents an expert consensus on the desired minimum knowledge for laypersons planning high altitude travel. Conclusion:Using the Delphi method, the STAK initiative yielded a set of 28 statements representing essential learning objectives for laypersons who plan to travel to high altitudes. This list could be used to develop educational interventions.

We have recently reported that hypobaric hypoxia (HH) reduces plasma volume (PV) in men by decreasing total circulating plasma protein (TCPP). Here, we investigated whether this applies to women and whether an inflammatory response and/or endothelial glycocalyx shedding could facilitate the TCCP reduction. We further investigated whether acute HH induces a short-lived diuretic response that was overlooked in our recent study, where only 24-h urine volumes were evaluated. In a strictly controlled crossover protocol, twelve women underwent two 4-day sojourns in a hypobaric chamber: one in normoxia (NX) and one in HH equivalent to 3,500m altitude. PV, urine output, TCPP, and markers for inflammation and glycocalyx shedding were measured repeatedly. Total body water (TBW) was determined pre- and post-sojourns by deuterium dilution. PV was reduced after 12h of HH and thereafter remained 230-330ml lower than in NX (p<0.0001). Urine flow was 45% higher in HH than in NX throughout the first 6h (p=0.01), but lower during the second half of the first day (p<0.001). 24-h urine volumes (p≥0.37) and TBW (p≥0.14) were not different between the sojourns. TCPP was lower in HH than in NX at the same time points as PV (p<0.001) but inflammatory or glycocalyx shedding markers were not consistently increased. As in men, and despite initially increased diuresis, HH-induced PV contraction in women is driven by a loss of TCPP and ensuing fluid redistribution, rather than by fluid loss. The mechanism underlying the TCPP reduction remains unclear but does not seem to involve inflammation or glycocalyx shedding.

No abstract