The effects of water and salt intake upon the performance of men working in hot and humid environments

Maintenance of Plasma Volume and Serum Sodium Concentration Despite Body Weight Loss in Ironman Triathletes

“…In 1955, Ladell made early reference to this ''free circulating water'' and stated that until this approximately 2-L fluid ''reserve'' was used up, bodily function would be unimpaired. 46 This hypothesized ''fluid reserve'' is likely contained within the interstitial fluid of the extracellular fluid compartment. 8,47 Water lost through sweat is drawn from the interstitial fluid surrounding the sweat glands and replenished by the filtration of fluid from local capillaries.…”

Realising the Potential of Urine and Saliva as Diagnostic Tools in Sport and Exercise Medicine

“…Hypo-hydration has a concentration effect, while hyper-hydration has a dilution effect. In exercise specifically, the consumption of water and carbohydrate-electrolyte formulations is known to influence temperature regulation, physiological strain, and endurance during exercise [219][220][221][222]. This is a key indication of how vital hydration status is for exercise performance and, therefore, the challenges associated with urinary biomarker correction and hydration status.…”

Proceedings of the Physiological Society

“…* Present address: Chemical Defence Experimental Establishment, Porton, near Salisbury, Wilts. 52 P SOCIET Y, 14-15 DECEMBER 1956 53P Further examination of heart rate/rectal temperature correlations (Ladell & Watkins, 1957) gave no indication of a ceiling heart rate being reached. By comparison with Europeans (Ladell, 1955) these men had higher heart rates at lower temperatures, but the rate of increase with rising temperature was 3 beats/min/' F less, either working or resting, so that at high rectal temperatures heart rates were slower.…”