Aim. The purpose of the present study was to analyze the effects of Pilates on the volume of iliopsoas muscles.
Methods. Magnetic resonance imaging (MRI) was used to determine the volume of gluteal muscles in 9 non-active healthy women, before and after 36 wk of a standardized Pilates training program (50 min/session, 2 session/wk). The MRI images (L1-L2 intervertebral disc to pubic symphysis), were used to calculate the volume iliopsoas. Pre- and postraining comparisons were carried out using the paired Student's t-test. Significant differences were assumed when P < 0.05.
Results. Before Pilates, the volume of iliopsoas was similar in the dominant and in the non-dominant side (248,4 ± 43.4 vs. 251.8 ± 31.8 cm3, P = 0.4). Compared to pre-training, after Pilates the volume of iliopsoas was similar in the dominant (248,4 ± 43.4 vs 256.5 ± 31.8 cm3, respectively, P = 0.4) and in the non-dominant side (251.8 ± 31.8 vs 258.1 ± 34.0 cm3, respectively, P = 0.4). The degree of asymmetry in muscle volume between the dominant and the non-dominant side was also similar before and after Pilates (1.3 ± 4.4 vs. 0.6 ± 1.7%, respectively, p = 0.7).
Conclusion. This study shows that 36 wk of Pilates do not increase the volume of the iliopsoas muscle group in physically non-active healthy women. The iliopsoas muscles play a secondary role on lumbo-pelvic control during a standardized Pilates training program.
Corresponding author. cecilia.dorado@ulpgc.es
