title: Electromechanical delay of abdominal muscles is modified by low back pain prevention exercise.
abstract: The objective of the research was to assess the effect of a 4-week-long training program on selected parameters: electromechanical delay (EMD) and amplitude of electromyographic signal (EMG). Fourteen female students of the University School of Physical Education participated in the study. Torques and surface electromyography were evaluated under static conditions. Surface electrodes were glued to both sides of the rectus abdominis (RA), external oblique (EO), and erector spinae (ES) muscles. The 4-week-long program was aimed at strengthening the abdominal muscles and resulted in increased EMD during maximum torque production by flexors of the trunk, increased amplitudes of the signals of the erector spinae ( p = 0.005), and increased EMG amplitude asymmetry of the lower ( p = 0.013) and upper part ( p = 0.006) of the rectus abdominis muscle. In a training program composed of a large number of repetitions of strength exercises, in which the training person uses their own weight as the load (like in exercises such as curl-ups), the process of recruitment of motor units is similar to that found during fatiguing exercises and plyometric training.
authors.affiliation: Department of Biomechanics, University School of Physical Education in Wrocław, Wrocław, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Szpala
authors.affiliation: Department of Biomechanics, University School of Physical Education in Wrocław, Wrocław, Poland.
authors.forename: Alicja
authors.initials: A
authors.lastname: Rutkowska-Kucharska
authors.affiliation: Department of Computer Science and Management, Wrocław University of Technology, Wrocław, Poland.
authors.forename: Jaroslaw
authors.initials: J
authors.lastname: Drapala
mesh_terms: D000009:Abdominal Muscles / Q000502:physiology*; D000328:Adult; D056966:Excitation Contraction Coupling / Q000502:physiology*; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000503:physiopathology* / Q000517:prevention & control*; D053580:Muscle Strength / Q000502:physiology*; D009469:Neuromuscular Junction / Q000502:physiology; D064797:Physical Conditioning, Human / Q000379:methods*; D011930:Reaction Time / Q000502:physiology; D009435:Synaptic Transmission / Q000502:physiology; D055815:Young Adult