A measure of the acidity, neutrality, or alkalinity of blood (see pH). At rest, blood pH is slightly alkaline (about pH 7.4). At exercise intensities above 50% maximal aerobic capacity, the blood becomes more acidic as respiration becomes more dependent on anaerobic metabolism. At first the decrease in pH is gradual, but it becomes rapid near the point of exhaustion. Blood pH values of less than 7.0 have been recorded following maximal sprint-type exercise. See also blood lactate.
Subjects: Sports and Exercise Medicine.