Influence of Morphology and Strength on Front Crawl Swimming Speed in Junior and Youth Age-Group Swimmers.

Abstract

Strzała, M, Stanula, A, Krężałek, P, Ostrowski, A, Kaca, M, and Głąb, G. Influence of morphology and strength on front crawl swimming speed in junior and youth age-group swimmers. J Strength Cond Res 33(10): 2836-2845, 2019-This study, conducted in 2 male age groups, was aimed at analyzing the influence of body properties, dry-land strength and swimming strength on 50-m crawl (VCrawl). We examined 2 competitive groups, Youth (20.6 ± 1.05) and Junior (17.3 ± 0.59), based on (a) body mass (BM) and lean body mass (LBM), body height (BH) and total body length (TBL), and arm span (AS); (b) countermovement jump (CMJ) and maximum isometric strength of elbow and knee joints; and (c) tethered crawl strength. We hypothesized that a higher relationship of strength indices in younger swimmers in VCrawl and tethered swimming would be a better sprint performance predictor. The Junior group revealed a significant relationship between somatic traits (BM r = 0.63; BH r = 0.55; TBL r = 0.58; AS r = 0.52 with p ≤ 0.05 LBM r = 0.78; with p < 0.01) and VCrawl, whereas such interplay was not found in the Youth group. General dry-land strength indices CMJ (cm), CMJ (J) or isometric strength of knee joint muscle flexors and extensors (r = 0.57; r = 0.69; r = 0.56; r = 0.57, respectively) also significantly correlated with VCrawl only in the Junior group. The Junior group's tethered swimming strength had a higher but not a significant relationship with VCrawl. The Youth group instead achieved significantly higher VCrawl and stroke rate (SR). The SR revealed (r = 0.41, p = 0.014) a relationship with VCrawl only after the combination of both groups. This study demonstrates a better strength relationship with VCrawl in the younger Junior group. In the future, the evaluation of sprint swimming aptitudes, besides on the basis of somatic traits and properties of dry-land or water strength measurement, should be complemented by measurements of real sprint swimming technique parameters.