Multivariate Analysis in the Maximum Strength Performance

Author(s):Show less -

de Souza, E. O. ^[1] ; Tricoli, V. ^[1] ; Paulo, A. C. ^{[1, 2, 3]} ; Silva-Batista, C. ^[1] ; Cardoso, R. K. ^[1] ; Brum, P. C. ^[1] ; Bacurau, A. V. N. ^[1] ; Laurentino, G. ^[1] ; Neves-, Jr., M. ^[4] ; Aihara, A. Y. ^[5] ; Ugrinowitsch, C. ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Sport, Sch Phys Educ & Sport, BR-05508 Sao Paulo - Brazil

^[2] Univ Paulista UNIP, Dept Phys Educ, Sao Paulo - Brazil

^[3] Univ Nove Julho, Dept Phys Educ, Sao Paulo - Brazil

^[4] Univ Sao Paulo, Sch Med, BR-05508 Sao Paulo - Brazil

^[5] Univ Fed Sao Paulo, Dept Radiol, Sao Paulo - Brazil

• Document type: Journal article
• Source: INTERNATIONAL JOURNAL OF SPORTS MEDICINE; v. 33, n. 12, p. 970-974, DEC 2012.
• Web of Science Citations: 3

Abstract

This study performed an exploratory analysis of the anthropometrical and morphological muscle variables related to the one-repetition maximum (1RM) performance. In addition, the capacity of these variables to predict the force production was analyzed. 50 active males were submitted to the experimental procedures: vastus lateralis muscle biopsy, quadriceps magnetic resonance imaging, body mass assessment and 1RM test in the leg-press exercise. K-means cluster analysis was performed after obtaining the body mass, sum of the left and right quadriceps muscle cross-sectional area (Sigma CSA), percentage of the type II fibers and the 1RM performance. The number of clusters was defined a priori and then were labeled as high strength performance (HSP1RM) group and low strength performance (LSP1RM) group. Stepwise multiple regressions were performed by means of body mass, Sigma CSA, percentage of the type II fibers and clusters as predictors' variables and 1RM performance as response variable. The clusters mean +/- SD were: 292.8 +/- 52.1 kg, 84.7 +/- 17.9 kg, 19249.7 +/- 1645.5 mm(2) and 50.8 +/- 7.2% for the HSP1RM and 254.0 +/- 51.1 kg, 69.2 +/- 8.1 kg, 15483.1 +/- 1 104.8 mm(2) and 51.7 +/- 6.2 %, for the LSP1RM in the 1RM, body mass, Sigma CSA and muscle fiber type II percentage, respectively. The most important variable in the clusters division was the Sigma CSA. In addition, the Sigma CSA and muscle fiber type II percentage explained the variance in the 1RM performance (Adj R-2 = 0.35, p = 0.0001) for all participants and for the LSP1RM (Adj R-2 = 0.25, p = 0.002). For the HSP1RM, only the Sigma CSA was entered in the model and showed the highest capacity to explain the variance in the 1RM performance (Adj R-2 = 0.38, p = 0.01). As a conclusion, the muscle CSA was the most relevant variable to predict force production in individuals with no strength training background. (AU)

• FAPESP's process: 07/02738-6 - Effect of concurrent training on gene expression associated with muscle hypertrophy
• Grantee: Eduardo Oliveira de Souza
• Support Opportunities: Scholarships in Brazil - Master