INTRODUCTION: Tervo and Jensen (2009) found that stand-up Nordic skiers, using a sit-ski device obtained peak linear velocity at the same point during the poling cycle as a sit-ski athlete. Tervo et al (2010) found that the rectus femoris was highly activated in sit-skiing and more-so than in stand-up skiing. However, no studies have examined differences in shoulder (SH), elbow (EL), and trunk (TR) movement during these two versions of double poling. Thus the purpose of this study was to compare joint range of motion (ROM) while standing and sitting using a double pole ergometer. METHODS: Fourteen collegiate Nordic skiers performed two VO2peak tests, at least 24 hours apart, using the double pole technique on a modified VASA Ergometer (Essex Junction, Vermont, USA). One test was performed in the standing position and the other in a seated position. Tests began at a cadence of 40 and increased by 5 strokes per minute to exhaustion. Sagital Video analysis (60 Hz) of each exercise was performed with markers on the acromion process, lateral humeral epicondyle, styloid process, and greater trochanter. ROMs were determined using Motus 8.5 (Peak Performance Technologies, Englewood, CO) and compared across stages and between positions using SPSS 17.0 (SPSS, Chicago, IL). RESULTS & DISCUSSION: Mean data for ROM (±s.d.) are presented in Table 1. There were no significant differences or interaction in EL ROM for the positions or across stages (p > 0.05). Shoulder ROM was different for the positions and there was an interaction (p < 0.05). Trunk ROM displayed an interaction as well as position differences and stage 4 differed from stages 2 and 3 (p < 0.05). Thus skiers appear to decrease ROM at the shoulder while increasing trunk movement when changing from the seated to standing position. In addition trunk movement decreases with increasing workload, especially in seated double pole ergometry. In agreement with Tervo et al. (2010), these findings indicate that stand up Nordic skiers move the upper body in a different way during seated double pole ergometry. CONCLUSION: Changes in TR and SH ROM suggest that stand-up double pole ergometry should not be used as a surrogate for seated double pole ergometry.
© Copyright 2010 Book of Abstracts. 5th International Congress on Science and Skiing, Dec. 14 - 19, 2010, St. Christoph am Arlberg. Published by University of Salzburg, Interfakultärer Fachbereich Sport- und Bewegungswissenschaft/USI. All rights reserved.