Blood lactates after prolonged severe exercise

Abstract

Blood was drawn from cross-country skiers at 1–3 min after the finish in competitions on distances from 10 to 85 km and the blood lactate determined. Despite a maximal effort of the skiers, accentuated at the end of the race, there was a successive decrease in the blood lactate concentration with work time. After a 10-km race, work time 35–36 min, the average was 139 mg/100 ml of blood (12.5 mEq/liter); after a 30-km race, with a time of 1 hr 50 min-1 hr 56 min, the mean value was 68 mg/100 ml (6.1 mEq/liter); and after a 50-km race, work time 3 hr 6 min-3 hr 18 min, 39 mg/100 ml (3.5 mEq/liter). A lactate concentration exceeding 100 mg/100 ml is a common finding after maximal muscular exercise involving large muscles. The explanation for the low values after prolonged maximal work, indicating a different kind of fatigue, is presently obscure. Data are presented on the oxygen uptake attained during skiing at actual racing speed (average Vo2 = 4.45 liters/min). Submitted on July 16, 1962

Serum Electrolyte, Fluid and Acid-Base Balance after Prolonged Heavy Exercise at Low Environmental Temperature

“…T h e slight increase in lactic acid concentration observed immediately after the race is in accordance with other data after prolonged heavy exercise (1,18), the ability to produce lactic acid at maximal exertion decreasing with the duration of the preceding exercise.…”

Blood lactate concentration following maximum exercise in trained subjects.

“…Venous blood lactate concentration has long been considered a useful measurement in quantifying the extent of anaerobic metabolism during exercise and may be used as an objective criterion of the degree of exhaustion, (Astrand et al, 1963). The extent to which venous blood lactate reflects the muscle lactate production is unclear, (Graham, 1978).…”

Section A. BIOCHEMISTRY

“…ski race (Astrand, Hallback, Hedman and Saltin, 1963). These observations suggested that post-exercise ketosis, first reported by Courtice and Douglas (1936), might depend upon the athletic training of the exercised subject.…”