Original articles  EXERCISE PHYSIOLOGY AND BIOMECHANICS 

The Journal of Sports Medicine and Physical Fitness 2002 September;42(3):274-81

Copyright © 2009 EDIZIONI MINERVA MEDICA

language: English

Leg strength and stiffness as ability factors in 100 m sprint running

Bret C. ^{1, 2}, Rahmani A. ¹, Dufour A. B. ³, Messonnier L. ^{1, 4}, Lacour J. R. ¹

¹ Laboratoire de Physiologie de l’Exercice, GIP Exercice, Faculté de Médecine Lyon-Sud, Oullins Cedex, France 2 Centre de Recherche et d’Innovation sur le Sport (CRIS) and 3 Laboratoire de Biométrie et de Biologie Evolutive, Université Claude Bernard - Lyon I, Villeurbanne Cedex, France 4 Laboratoire de Modélisation des Activités Sportives, Campus Universitaire, Le Bourget du Lac Cedex, France

Background. The pur­pose of ­this ­study was to deter­mine the impor­tance of leg ­strength and stiff­ness rel­a­tive to i) 100 m ­sprint per­for­mance, ii) ­mean ­speed on the ­three phas­es of the 100 m ­race (30-60-100 m) and iii) the ­speed dif­fer­enc­es ­between ­these phas­es.
Methods. Nineteen region­al to nation­al lev­el ­male sprint­ers com­pet­ed in a 100 m ­race. Video anal­y­sis was ­used to deter­mine ­mean veloc­ity param­e­ters. Two sub­groups ­were creat­ed ­since ­some of the run­ners ­decreased ­their veloc­ity dur­ing the ­third ­phase (G1), where­as oth­ers main­tained or accel­er­at­ed it (G2). Leg ­strength (con­cen­tric ­half-­squats - coun­ter move­ment ­jump) and stiff­ness (hop­ping) ­were deter­mined. Simple (r) and mul­ti­ple regres­sions (R) ­were ­used.
Results. The ­mean per­for­mance ­over 100 m was 11.43 sec (10.72-12.87 sec). The con­cen­tric ­half-­squats ­were relat­ed to 100 m (r=0.74, p<0.001) and to the ­mean ­speed of ­each ­phase (R=0.75, p<0.01). The coun­ter move­ment ­jump was relat­ed to 100 m (r=0.57, p<0.05) and was the pre­dic­tor of the ­first ­phase (r=0.66, p<0.01). The hop­ping ­test was the pre­dic­tor of the two ­last phas­es (R=0.66, p<0.05). Athletes who had the great­est leg stiff­ness (G1) pro­duced the high­est accel­er­a­tion ­between the ­first and the sec­ond phas­es, and pre­sent­ed a decel­er­a­tion ­between the sec­ond and the ­third ­ones.
Conclusions. The con­cen­tric ­half-­squats ­test was the ­best pre­dic­tor in the 100 m ­sprint. Leg stiff­ness ­plays a ­major ­role in the sec­ond ­phase.