Assessment Of Maximal Lactate Steady State Response In Race Walking

Introduction:During race walking, the key of race walkers is to keep fast speed without the accumulation of lactate for a long time. Compared to the individual lactate threshold, Maximal lactate steady state (MLSS) could reflect the state of body metabolism during the submaximal exercise more effectively. Determination of MLSS used to come out in several days after several repeated load test programs.. This study is designed to investigate the validity of lactate minimum test (LMT) in the determination of MLSS, to analysis the appropriate training intensity of training in race walking according to the test results and to determine whether a relationship between the average speed during time trial and the MLSS or not. And then, assessment of maximal lactate steady state response in race walking was turned out.Methods:The first step was to design different exercise programs of LMT. And then, through the pre-test motion parameters were repeatedly amended to determine appropriate programs for race walking—6 male race walkers (mean±SD, age16±1 yr, height 175.33±4.57 cm, weight 64.28±3.74 kg) performed a 200-m walking to elevate the lactate and then after recovery of 10-min, the subjects performed an incremental load test consisting of a series of seven 400-m walking tests with 30s interval for blood sampling. The intensities of the 400-m series were 78,81,84, 87,90,93 and 96% of the 1500-m speed. The MLSS was determined by visual inspection as the point corresponding to the lowest lactate. Then subjects completed 5-km and 10-km walking time trial to determine average speed. Bivariate correlation analysis was performed to inspect the relationship between the average speed of 5km and the speed of MLSS, as well as the case of 10km. And then, the training situation of athletes in Harbin Sports Schools was monitored through MLSS.Results:In this study, kinetics of lactate of four race walkers in six responded a "U" shaped curve during the incremental test after blood lactate elevation. The lowest point of "U" shaped curve was the MLSS concentration,3.25±0.37mmol/l, the speed of MLSS is 12.5±0.54km/h. The results showed that there was a significant relationship between the average speed of 10km walking time trial and VMLSS, r=0.996; but no correlation with V5km. The lactate of the main training course was greater than MLSS's, while the speed was almost equal to MLSS.Discussion/Conclusion:(1) The MLSS of race walking could be tested in one day through the lactate minimum test. And the MLSS concentration of youth race walkers was less than lactate threshold (4mmol/l). (2) 10km walking time trial could be used to estimate the MLSS of youth race walkers.论文随机验证编号:BT68218472170...