title: Time trials predict the competitive performance capacity of junior cross-country skiers.
abstract: OBJECTIVE
  This study investigated whether there is a correlation between time-trial performance and competitive performance capacity of male and female junior cross-country skiers and sought to explain sex-specific competitive performance capacity through multiple-regression modeling.
  
  
  METHODS
  The International Ski Federation's (FIS) junior ranking points for distance (FISdist) and sprint (FISsprint) competitions were used as performance parameters. A total of 38 elite junior (age 18.5 ± 1.0 y) cross-country skiers (24 men and 14 women) completed 3 time-trial tests: a 3-km level-running time trial (TTRun), a 2-km moderate uphill (1.2° slope) roller-skiing time trial using the double-poling technique (TTDP), and a 2-km uphill (2.8° slope) roller-skiing time trial using the diagonal-stride technique (TTDiag). The correlations were investigated using Pearson correlation analysis, and regression models were created using multiple-linear-regression analysis.
  
  
  RESULTS
  For men, FISsprint and FISdist were correlated with the times for TTRun, TTDP, and TTDiag (all P < .001). For women, FISsprint was correlated with the times for TTRun (P < .05), TTDP (P < .01), and TTDiag (P < .01), whereas FISdist was correlated only with the times for TTDP (P < .01) and TTDiag (P < .05). The models developed for FISdist and FISsprint explained 73.9-82.3% of the variance in the performance capacity of male junior cross-country skiers. No statistically valid regression model was found for the women.
  
  
  CONCLUSIONS
  Running and roller-skiing time trials are useful tests for accurately predicting the performance capacity of junior cross-country skiers.
authors.affiliation: Dept. of Health and Social Sciences, Dalarna University, Falun, Sweden.
authors.forename: Magnus
authors.initials: M
authors.lastname: Carlsson
authors.forename: Tomas
authors.initials: T
authors.lastname: Carlsson
authors.forename: Daniel
authors.initials: D
authors.lastname: Hammarström
authors.forename: Christer
authors.initials: C
authors.lastname: Malm
authors.forename: Michail
authors.initials: M
authors.lastname: Tonkonogi
mesh_terms: D000293:Adolescent; D054874:Athletic Performance / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D012044:Regression Analysis; D012420:Running / Q000502:physiology; D012737:Sex Factors; D012865:Skiing / Q000502:physiology*; D013997:Time Factors