Delayed acclimatization of the ventilatory threshold in healthy trekkers.

Journal article

OBJECTIVE: To test the hypothesis that acclimatization to high altitude results in an improvement of the ventilatory threshold (VT). METHODS: Eight lowlanders underwent cardiopulmonary exercise testing with a cycle ergometer to determine VT and peak oxygen uptake (Vo2peak) in Coventry, United Kingdom (altitude: 80 m), on arrival in leh, india (altitude: 3500 m), and after 12 days of acclimatization that included a 5-day high altitude trek up to 4770 m. RESULTS: Vo2peak fell on arrival at 3500 m and remained depressed at 12 days. VT was depressed on arrival at high altitude and was further depressed at 12 days. VT as a proportion of the Vo2peak was decreased on arrival at high altitude, and after acclimatization, this relationship was further decreased. CONCLUSIONS: Individuals who are sedentary or not participating in regular physical training appear to require a longer period of acclimatization than trained athletes. With the increasing numbers participating in high-altitude trekking and charity climbs of peaks, such as Mt. Kilimanjaro, this information has clinically significant practical implications for those leading or acting as medical advisors.

Authors: Myers, S; Biccard, B; Chan, C; Imray, C; Wright, A

• Journal: Wilderness and environmental medicine
• Volume: 19
• Issue: 2
• Pages: 124-128
• Publication date: 2008-01-01
• DOI: 10.1580/07-weme-br-1271.1
• EISSN: 1545-1534
• ISSN: 1080-6032
• Language: English
• Keywords: Birmingham Medical Research Expeditionary Society; Male; Altitude Sickness; Acclimatization; Maximal Voluntary Ventilation; Female; Humans; Altitude; Oxygen Consumption; Anoxia; Exercise Test; Adult