Changes Of Serum Enzyme Activity During World Ranking Races In World-class Canoe Slalom Paddler: 2805 Board #120 May 29, 3

Whitewater slalom (canoe/kayak slalom) is a competitive sport whose the aim is to navigate a decked canoe or kayak through a course of hanging gates on river rapids in the fastest time possible. The athletes need to demonstrate both immense skill and physical strength in this sport discipline. We previously reported that serum enzyme activity increased after domestic canoe slalom race, and serum creatine kinase (CK) activity showed positive correlations with a number of total paddling in Japanese competitive paddlers. PURPOSE: The aim of this study was to examine serum enzyme activities which related to muscle damage during the actual international canoe slalom competition in world-class canoe slalom paddler. METHODS: A world-class canoe slalom paddler was subjected to collect blood samples in two world ranking races. One world-cup race and one world championship were selected for this testing. Blood samples were collected before race, just after the first and second race of qualification, just after the semifinal/final race, six hours, and twenty four hours after the semifinal/final race. Visual analog scale for delayed onset of muscle soreness (DOMS) was also measured at the same time during competitions. RESULTS: In world-cup, blood lactate concentration increased after every race (after qualification, 8.1 mmol/L; after semifinal, 15mmol/L; and after final, 14.5 mmol/L, respectively) from the pre value (1.7 mmol/L). Blood lactate concentration also showed dramatic increase in world championship (1.3 mmol/L to 12.5 mmol/L) after semifinal. In both of the competitions, serum CK activities increased just after races (178 IU/L in world-cup, 159 IU/L in world championship) and gradually increased or remained on its level by six hours after the competition (195 IU/L in world-cup and 157 IU/L in world-championship) from resting serum CK activity (99 IU/L). CONCLUSIONS: We confirmed similar time-course changes of serum CK activites during international competition in world-class canoe slalom paddler as previously reported in Japanese competitive paddlers. Increase of blood lactate concentration and percentage of serum CK activity increase were relatively higher than those of Japanese competitive paddlers.