Affiliations: [a] School of Health, School of Physical Education,
University of São Caetano do Sul, São Caetano do Sul, Brazil | [b] School of Physical Education, University of Campinas,
Campinas, Brazil | [c] School of Physical Education, Pontifical Catholic
University of Campinas, Campinas, Brazil
Note: [] Corresponding author: Daniel Leite Portella, Rua Carlos Escobar
145/63, Santana, São Paulo, 02013-050, São Paulo, Brazil. Tel.: +55 11
95352 8441, +55 11 4239 3311; E-mail: dlportella@uol.com.br, daniel.portella@uscs.edu.br
Abstract: BACKGROUND: Few studies thus far have investigated the
relationship between body composition (in particular, bone components) and
isokinetic strength performance. OBJECTIVE: To determine the relationship
between bone mineral content (BMC), bone mineral density (BMD), and fat-free
mass (FFM) with isokinetic strength performance variables in professional
soccer players. METHODS: We recruited 20 elite male soccer players from
the Brazilian league's first division teams. Participants underwent a
concentric isokinetic evaluation of knee flexor and extensor muscles.
Dual-energy X-ray absorptiometry (DXA) was used to determine body composition.
The relationships between variables were analyzed using Pearson's
product-moment correlation coefficient. RESULTS: Body composition
variables were correlated with the strength output of knee flexor and extensor
muscles in both lower limbs. FFM and BMC explained at least 50% of the
variation in peak knee flexion and extension torque while BMD did not have the
same effect. CONCLUSIONS: The relationships reported in this study
indicate that the use of isokinetics and DXA in soccer players should be
further investigated both for measuring athletic performance and for relevant
clinical assessment.
