CHARACTERISTICS OF COMPETITIVE FEMALE ALPINE SKIERS 8-18 YEARS 967

Abstract

This study compares the growth status, sexual maturation and motor performance of trained female alpine skiers from late childhood through adolescence with reference data for corresponding samples of non-athletes. The sample included 132 select female alpine skiers 8-18 years of age, who were training at race camps in Mt. Hood, Oregon, in the summer of 1994. Anthropometric dimensions included mass, height, sitting height, skeletal breadths, limb girths, and skinfolds. Measurement variability was well within the tolerance limits of national surveys. Relative fatness was estimated with a prediction equation developed on age group swimmers of the same age range. Pubertal status was based on self-assessment of breast and public hair development, menarcheal status, and recalled age at menarche. Five tests of motor skill were used: vertical jump (VJ), high box (BOX), hexagonal obstacle(HEX), double leg lateral vault (TLEG), and Bass test of dynamic balance(BAL). Reliabilities of the motor tests ranged from 0.68 (BAL) to 0.93 (VJ). Stature, weight, sitting height, biacromial and bicristal breadths approximated the medians of U.S. reference data and were normally distributed about the medians. Skinfold thicknesses and estimated relative fatness were less than corresponding values for non-athletes. The distribution of secondary sex characteristics overlapped the reference data with a tendency toward somewhat later maturation which was consistent with the mean recalled age at menarche. 13.6 ± 0.75 years. VJ reaches a plateau at about 13.0 years in the skiers, while BOX jumping tends to increase with age. Performance on HEX and TLEG showed a dramatic improvement during early adolescence with a plateau in the mid-teens, while BAL performance showed no clear improvement with age. The results suggest that female alpine skiers are similar in size and proportions, but are leaner and more powerful compared to non-athletes from late childhood through adolescence.