Blood lactate, glycerol and catecholamine in arm strokes, leg kicks and whole crawl strokes

Lactate, glycerol, and catecholamine in the venous blood were determined in 8 recreational swimmers following 60 sec of supramaximal arm strokes, kicks and the whole swim. The mean velocity of a whole stroke was higher than both arm strokes and kicks, and the mean velocity of arm strokes was higher when compared with kicks. There was a significant relationship between the mean velocity of arm strokes and the whole swim (r = 0.90; p less than 0.01). Peak blood lactate in the whole swim was higher than arm strokes (p less than 0.01) and kicks (p less than 0.01), and peak blood lactate in arm strokes was higher compared to kicks (p less than 0.01). The correlation coefficients between mean velocity and peak blood lactate in arm strokes, legs kick and whole swim were r = 0.72 (p less than 0.05); r = 0.61 (n.s.) and r = 0.35 (n.s.), respectively. These results suggest (1) that lactate in the blood during the whole crawl stroke originates predominantly from the muscle groups which work the arm and (2) that glycogen included in the muscles of the upper body which is used during arm strokes was easily convertible into the propelling force during arm swim, while additional energy from the leg muscles is not fully sufficient to increase propulsion force in a linear manner.