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Critical Power Is More Strongly Associated With Rowing Performance Than the Second Lactate Threshold
Dan D Dwyer1, Kieron D Lester1, Rodney Siegel2
1Centre for Sport Research in the Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, VIC, Australia.
Purpose:
This study aimed to determine the level of agreement between critical power (CP) and the second lactate threshold in rowers, examine their respective relationships with rowing performance, and assess the accuracy of the CP model in predicting 2000-m rowing time.
Methods:
Previously collected data were retrieved from well-trained, national or international standard male (n = 20) and female (n = 18) rowers who underwent testing at their respective clubs administered by a sport scientist. The second lactate threshold was determined using the modified Dmax (ModDmax) and LogPoly-modified Dmax (LogPoly) methods via an incremental rowing ergometer test. Time-trial tests consisted of a 2000-m performance trial, with the remaining tests (500 m and either 5000 m or 6000 m) used to determine CP and work above CP (W') via the linear 1/time model.
Results:
Associations between CP, ModDmax, and LogPoly were moderate to strong (r2 = .49-.70); however, power output at CP (311 [67] W) was lower (P < .001) than at ModDmax (324 [68] W) and LogPoly (323 [67] W). Of the 3 methods, CP achieved the highest association with rowing performance (r2 = -.81; P < .001), followed by ModDmax and LogPoly (both r2 = -.75; P < .001). The inclusion of W' in the full CP model predicted 2000-m time that was highly correlated (male r2 = .92 and female r2 = .81, P < .001) with actual time.
Conclusions:
Although agreement in absolute power output between CP, ModDmax, and LogPoly was not confirmed, associations between them were strong, and all had moderate to high correlations with 2000-m rowing performance.
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