THE EFFECT OF EXERCISE UPON DIASTOLIC HEART SIZE

Abstract

The heart tends to increase in size during short (10 min.) and long (30 min.) periods of severe exercise, the greatest increase being noted in the latter. Moderate exercise produces little variation in size. After moderate exercise and short periods of severe exercise cardiac area and transverse diameter tend to decrease. After long periods of severe exercise the heart may not recover its orginal volume in 5 min. Minute volume is markedly increased during exercise, and is greatest in long continued severe exercise. After exercise rather abrupt and marked diminution of minute volume is noted. The low figures obtained for minute volume in some individuals following exercise probably indicate an increased stroke volume during exercise which persists for more than 5 min. after the cessation of exercise.