Grade Influences Blood Lactate Kinetics During Cross-Country Skiing
The purpose of this study was to examine the effects of level vs. graded skate skiing on capillary blood lactate (BLa), heart rate (HR), oxygen consumption (V_ O2), and training intensity prescriptions. Eleven Nordic skiers completed 2 submaximal skate roller skiing treadmill protocols during which intensity was increased either by grade (Ginc) or by speed (Sinc). The protocols were compared for prethreshold BLa, HR, and V_ O2 at lactate threshold (LT) and the HR/V_ O2 relationship. Additionally, double-pole (primarily upper body) and skating (arms and legs combined) protocols were used to measure peak V_ O2 and peak HR. Heart rate and V_ O2 at LT were lower during Ginc compared with Sinc (154.9 6 6.8 b min21 vs. 162.0 6 9.1 b min21 and 46.3 6 2.8 ml kg21 min21 vs. 49.1 6 1.6 ml kg21 min21 , respectively, both p , 0.01). Prethreshold BLa and the HR/V_ O2 relationship were not different between the submaximal protocols. V_ O2peak and HRpeak were higher in skating compared with double poling (64.6 6 1.8 ml kg21 min21 vs. 60.3 6 2.8 ml kg21 min21 , 192.6 6 5.8 b min21 vs. 187.8 6 6.7 b min21 , respectively, both p , 0.01). Greater reliance on upper-body musculature during graded skiing and its associated lower aerobic capacity increases BLa when compared with level skiing. The leftward shift in the BLa vs. intensity curve during uphill skiing should be recognized to properly prescribe training intensity as well as interpret laboratory results.
Journal of Strength and Conditioning Research
Digital Object Identifier (DOI)
D.P. LaRoche, M. Amann, K.W. Rundell. (2010) Grade influences blood lactate kinetics during cross-country skiing. Journal of Strength and Conditioning Research. 24(1):120-127.
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