Arthur R Bradwell1, Stephen D Myers2, Maggie Beazley3, Kimberly Ashdown2, Nick G Harris4, Susie B Bradwell5, Jamie Goodhart6, Chris H Imray7, Yashvi Wimalasena8, Mark E Edsell9, Kyle T S Pattinson10, Alex D Wright11, Stephen J Harris12. 1. School of Medicine, University of Birmingham, Birmingham (Drs Bradwell and Wright). Electronic address: a.r.bradwell@bham.ac.uk. 2. Department of Sport & Exercise Sciences, University of Chichester, Chichester (Dr Myers and Ms Ashdown). 3. Spencer Street Surgery, Carlisle (Dr Beazley). 4. Merrist Wood College Worplesdon Guildford (Mr Harris). 5. University College London, London (Ms Bradwell). 6. The University of Warwick, Coventry (Mr Goodhart and Dr Imray). 7. The University of Warwick, Coventry (Mr Goodhart and Dr Imray); University Hospital Coventry and Warwickshire NHS Trust, Coventry (Drs Imray and Wimalasena). 8. University Hospital Coventry and Warwickshire NHS Trust, Coventry (Drs Imray and Wimalasena). 9. St George's Healthcare NHS Trust, London (Dr Edsell). 10. Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford (Dr Pattinson). 11. School of Medicine, University of Birmingham, Birmingham (Drs Bradwell and Wright). 12. QinetiQ, Farnborough (Mr Harris), United Kingdom.
Abstract
OBJECTIVE: To assess the effect of acetazolamide (Az) on exercise performance during early acclimatization to altitude. METHODS:Az (250 mg twice daily) or placebo was administered for 3 days in a double-blind, randomized manner followed by a rapid ascent to 3459 m in the Italian Alps. Twenty healthy adults (age range, 18-67 years) were tested at 60% of sea-level peak power output for 15 minutes on a bicycle ergometer after 16 to 27 hours of altitude exposure. Exercise performance was measured in relation to peripheral oxygen saturations measured from pulse oximetry (Spo2), Lake Louise acute mountain sickness (AMS) score, and perceived difficulty. RESULTS: At altitude, resting Spo2 was higher in the Az group compared with placebo (P < .001). The highest AMS scores were in 4 of the placebo individuals with the lowest resting Spo2 (P < .05). During the exercise test, Spo2 fell in all but 1 subject (P < .001) and was reduced more in the Az group (P < .01). Four Az and 1 placebo subject were unable to complete the exercise test; 4 of these 5 had the largest fall in Spo2. The perception of exercise difficulty was higher in the Az subjects compared with those taking the placebo (P < .01). There was an age relationship with exercise limitation; 4 of the 9 older than 50 years failed to complete the test whereas only 1 of 11 younger than 50 years failed, and there were no failures in the 6 younger than 30 years (P < .05). CONCLUSIONS: In this study group, and despite higher resting Spo2, Az may have compromised exercise at 3459 m altitude during early acclimatization, particularly in older subjects.
RCT Entities:
OBJECTIVE: To assess the effect of acetazolamide (Az) on exercise performance during early acclimatization to altitude. METHODS:Az (250 mg twice daily) or placebo was administered for 3 days in a double-blind, randomized manner followed by a rapid ascent to 3459 m in the Italian Alps. Twenty healthy adults (age range, 18-67 years) were tested at 60% of sea-level peak power output for 15 minutes on a bicycle ergometer after 16 to 27 hours of altitude exposure. Exercise performance was measured in relation to peripheral oxygen saturations measured from pulse oximetry (Spo2), Lake Louise acute mountain sickness (AMS) score, and perceived difficulty. RESULTS: At altitude, resting Spo2 was higher in the Az group compared with placebo (P < .001). The highest AMS scores were in 4 of the placebo individuals with the lowest resting Spo2 (P < .05). During the exercise test, Spo2 fell in all but 1 subject (P < .001) and was reduced more in the Az group (P < .01). Four Az and 1 placebo subject were unable to complete the exercise test; 4 of these 5 had the largest fall in Spo2. The perception of exercise difficulty was higher in the Az subjects compared with those taking the placebo (P < .01). There was an age relationship with exercise limitation; 4 of the 9 older than 50 years failed to complete the test whereas only 1 of 11 younger than 50 years failed, and there were no failures in the 6 younger than 30 years (P < .05). CONCLUSIONS: In this study group, and despite higher resting Spo2, Az may have compromised exercise at 3459 m altitude during early acclimatization, particularly in older subjects.
Authors: Kelsley E Joyce; John Delamere; Susie Bradwell; Stephen David Myers; Kimberly Ashdown; Carla Rue; Samuel Je Lucas; Owen D Thomas; Amy Fountain; Mark Edsell; Fiona Myers; Will Malein; Chris Imray; Alex Clarke; Chrisopher T Lewis; Charles Newman; Brian Johnson; Patrick Cadigan; Alexander Wright; Arthur Bradwell Journal: BMJ Open Sport Exerc Med Date: 2020-03-26
Authors: Samuel J E Lucas; William L Malein; Owen D Thomas; Kimberly M Ashdown; Carla A Rue; Kelsey E Joyce; Charles Newman; Patrick Cadigan; Brian Johnson; Stephen D Myers; Fiona A Myers; Alexander D Wright; John Delamere; Chris H E Imray; Arthur R Bradwell; Mark Edsell Journal: BMJ Open Sport Exerc Med Date: 2021-01-07
Authors: Arthur R Bradwell; Kimberley Ashdown; Carla Rue; John Delamere; Owen D Thomas; Samuel J E Lucas; Alex D Wright; Stephen J Harris; Stephen D Myers Journal: BMJ Open Sport Exerc Med Date: 2018-01-23