Rate and amplitude of adaptation to two intensities of exercise in men aged 65-75 yr

Purpose: To test the hypothesis that in males aged 65-75 yr when the total amount of work completed is similar in endurance training three times per week for 12 wk at either 50% or 70% peak oxygen uptake (VO[subscript]2peak), there will be no significant difference in time course and amplitude of selected responses. Methods: Subjects were randomly assigned to three groups: 70% VO[subscript]2peak, N = 19; 50% VO[subscript]2peak, N = 16; or control group, N = 19. Subjects underwent a maximal cycle exercise test and blood volume (Evans Blue) determination at 0, 4, 8, and 12 wk. A submaximal exercise test (50 W) was conducted at weeks 0 and 12 where cardiac output was determined. The exercise groups maintained the same exercise relative intensity throughout the 12 wk and completed a similar total amount of work. Results: There were significant and similar increases in peak VO[subscript]2, power and heart rate (HR) for both exercise groups. Linear models best described the time course for peak power and HR in both exercise groups. In the 70% VO[subscript]2peak group, a quadratic model for VO[subscript]2 and a linear model for V[subscript]E, were the best fit. There were no significant changes in blood or plasma volume for any groups over the 12 wk. Significant increases in stroke volume and significant decreases in HR at 50 W were found in both exercise groups after training. Conclusion: Moderate-intensity cycle exercise (50% VO[subscript]2peak) to achieve 180-200 kJ per session, three times a week for 12 wk is a safe and effective stimulus for healthy asymptomatic men aged 65-75 yr to improve functional capacity in a primarily linear manner

Preferred learning modalities and practice for critical skills: a global survey of paediatric emergency medicine clinicians

Objective To describe senior paediatric emergency clinician perspectives on the optimal frequency of and preferred modalities for practising critical paediatric procedures. Methods Multicentre multicountry cross-sectional survey of senior paediatric emergency clinicians working in 96 EDs affiliated with the Pediatric Emergency Research Network. Results 1332/2446 (54%) clinicians provided information on suggested frequency of practice and preferred learning modalities for 18 critical procedures. Yearly practice was recommended for six procedures (bag valve mask ventilation, cardiopulmonary resuscitation (CPR), endotracheal intubation, laryngeal mask airway insertion, defibrillation/direct current (DC) cardioversion and intraosseous needle insertion) by at least 80% of respondents. 16 procedures were recommended for yearly practice by at least 50% of respondents. Two procedures (venous cutdown and ED thoracotomy) had yearly practice recommended by <40% of respondents. Simulation was the preferred learning modality for CPR, bag valve mask ventilation, DC cardioversion and transcutaneous pacing. Practice in alternative clinical settings (eg, the operating room) was the preferred learning modality for endotracheal intubation and laryngeal mask insertion. Use of models/mannequins for isolated procedural training was the preferred learning modality for all other invasive procedures. Free-text responses suggested the utility of cadaver labs and animal labs for more invasive procedures (thoracotomy, intercostal catheter insertion, open surgical airways, venous cutdown and pericardiocentesis). Conclusions Paediatric ED clinicians suggest that most paediatric critical procedures should be practised at least annually. The preferred learning modality depends on the skill practised; alternative clinical settings are thought to be most useful for standard airway manoeuvres, while simulation-based experiential learning is applicable for most other procedures