Metabolic Aspects of Acute Starvation In Normal Humans: Performance and Cardiovascular Evaluation

Abstract

Six healthy, normal adult males between the ages of 21 and 52 years fasted for a period of 10 days under conditions where water was available ad libitum. Basal oxygen uptakes (V̇o₂) in milliliters per minute and milliliters per kilogram body weight per minute corrected to standard conditions were significantly decreased during the fasting period. In submaximal work on the treadmill Ve_BTPS and Vo₂ in milliliters per minute and milliliters per kilogram per minute were significantly decreased during the fasting and rehabilitation periods, indicating a training effect. Maximal oxygen uptakes in milliliters per kilogram per minute were decreased during fasting, but the decrease was not statistically significant. Other maximal work measurements V̇e_BTPS, pulse rates and kilogram-meters of work per minute were also reduced in comparison to the control values, indicating a training effect. Electrocardiograms were significantly abnormal during the fasting phase and are considered to reflect a severe stress. One of the six subjects developed an abnormal electroencephalogram and was immediately removed from the study. Although physical performance was not significantly impaired during a 10-day starvation period, complete fasting without mineral supplementation is not recommended for troops on combat patrol.