ABSTRACT
BACKGROUND: The surface electromyography (sEMG), by evaluating the paraspinal muscle activity, may be used for diagnosis and evaluation of rehabilitation effectiveness patients with low back pain. OBJECTIVE: The purpose of the study was to determine the intra- and inter-session reliability of the measurement of the activity of the lumbar erector spinae (LES) activity (extension-flexion ratio). METHODS: The study included 21 asymptomatic subjects, aged 14 to 27 years, mean 23.7 ± 2.9. The LES muscle activity was assessed with using of the sEMG during forward trunk flexion and extension by two examiners. Based on the quotient of the LES muscle activity obtained during four concentric and eccentric tasks the extension-flexion ratio was calculated. RESULTS: The measurements displayed excellent or fair-to-good reliability (intraclass correlation coefficient ranged from 0.90 to 0.68). The typical error and coefficient of variations, ranged from 0.34 to 0.58, and from 13.7 to 21.9, respectively. CONCLUSIONS: The measurement of the extension-flexion ratio performed with the use of sEMG shows high level of intra- and inter-session reliability, suggesting that this parameter is a reliable tool in evaluation of the lumbar paraspinal muscles activity. However, the level of typical error should be taken into account.
Subject(s)
Electromyography/methods , Low Back Pain/rehabilitation , Muscle Contraction/physiology , Muscle, Skeletal/physiopathology , Adolescent , Adult , Female , Healthy Volunteers , Humans , Low Back Pain/physiopathology , Male , Range of Motion, Articular/physiology , Reproducibility of Results , Young AdultABSTRACT
OBJECTIVES: To assess abdominal muscles (AM) activity during prone, side, and supine bridge on stable and unstable surfaces (BOSU, Swiss Ball). DESIGN: Prospective comparison study. SETTING: Research laboratory. PARTICIPANTS: Thirty-three healthy volunteers from a university population. MAIN OUTCOME MEASURES: Surface electromyography of the rectus abdominis (RA), the external oblique (EO) and the internal oblique with the transversus abdominis (IO-TA). RESULTS: The AM exhibited the highest activity during prone bridge on a Swiss Ball (RA, EO, IO-TA 44.7 ± 19.2, 54.7 ± 22.9, 36.8 ± 18.6 in % of MVC, respectively). The lowest activity was observed during supine bridge on a stable surface and a BOSU (under 5.0). The lowest ratio analyzed on the basis of the relation of EO and IO-TA activity to RA was obtained during prone bridge on the Swiss Ball (1.4 ± 0.7 for EO, 0.9 ± 0.5 for IO-TA). The highest ratio was obtained during prone bridge on stable surface and supine bridges. CONCLUSIONS: The highest level of activity in the abdominal muscles is achieved during prone bridge on a Swiss Ball. However, this exercise provided the lowest activity of the EO and IO-TA in relation to RA. It is essential to conduct further studies verifying the usefulness of using Swiss Ball during core stability training.
