INFLUENCE OF SKI POLE GRIP ON UPPER BODY POWER OUTPUT IN NORDIC SKIERS

Abstract

PURPOSE This study tested the influence of three ski pole grip systems (pole grip + wrist strap) on upper body power output. Grip systems tested included a Traditional System (TS: Swix PC grip + simple strap), a Modern System (MS: Swix PC grip + SR94 strap), and an Integrated System (IS: Yoko 232 grip + Yoko 232 strap). METHODS Nine men (Mean±SD: 32±12 yrs, 177.0±5.4 cm, 75.1±6.0 kg) and two women (24±9 yrs, 174.6±3.6 cm, 67.3±7.7 kg), all of whom were experienced Nordic ski racers at the regional, national, or international level for the U.S., performed three successive upper body power (UBP) tests on a modified ergometer. The left and right hand holds on a Street Arm Ergometer were modified to connect with light weight wheeled platforms. Ski poles, which inserted into the top of each platform, were used to move the platforms independently along 3.0 m parallel aluminum rails such that a simulated upper body double-poling motion was possible. Power output from the ergometer was recorded using a standard computer interface and software (SMI, St. Cloud, MN). Using the modified ergometer, each subject performed three 15-sec tests of UBP using stiff Nordic ski poles (Yoko Power Poles; Pole lengths were appropriate for classic skiing) and a resistance corresponding to 3% of body mass. UBP was determined as the average of the five highest 1-sec power output values during the last 10 secs of each test. The three grip systems were tested in a counterbalanced order with 3–4 mins of rest between tests. UBP data were analyzed using a 2-Factor RM ANOVA and Sheffe's post-hoc test at the 0.05 alpha level. RESULTS UBP for the Integrated system was significantly higher than both Modern and Traditional Systems for absolute (Mean±SE: TS=162.5±7.0 W; MS=164.1±7.2 W; IS=169.2±6.8 W; P < 0.05) and relative power output (TS=2.21±0.06 W/kg; MS=2.23±0.07 W/kg; P < 0.05). CONCLUSIONS These results suggest that Nordic ski racing performance may be affected by choice of ski pole grip system by influencing UBP.