Abstract
Performance in competitive walking depends to a great extent on lipid utilization capacity. Therefore specific forms of training to improve lipid utilization capacity must be found in addition to standard training of circulatory capacity. We tried to determine the optimal speeds for these "lipolytic" forms of training from tread mill testing. Seven top walking athletes were tested on a treadmill with a slope of 2.5 %, first 10 min each at 9 and 11 km/h then increasing the speed 1 km/h each minute. From lactate levels we derived aerobe (2 mmol/l), individual anaerobe (increase of lactate curve 45°) and anaerobe thresholds (4 mmol/l lactate). Ath letes underwent field tests of 30 minutes duration at these speeds and we measured levels of FFA, glycerol, glucose, lactate, pyruvate and alanine. These parameters showed an increasing rate of glucose utilization at higher speed and higher lipo-- lysis, but beyond the individual anaerobic threshold no more increase in FFA utili zation. At anaerobe threshold there was a high utilization of pyruvate and lactate, but fatty acid utilization was quantitatively too small and speed too low for optimal walking. Therefore, we concluded that the optimal "lipolytic training tempo" is between aerobe and individual anaerobe thresholds. Intensive endurance training for both high glycolytic and circulatory capacity is still possible at the anaerobe threshold. Speeds from treadmill tests at a slope of 2.5 to 3 % are transferable to training.