title: Pelvic floor muscle contraction and abdominal hollowing during walking can selectively activate local trunk stabilizing muscles.
abstract: BACKGROUND
  Trunk muscle exercises are widely performed, and many studies have been performed to examine their effects on low back pains. However, the effect of trunk muscles activations during walking with pelvic floor muscle contraction (PFMC) and abdominal hollowing (AH) has not been clarified.
  
  
  OBJECTIVE
  To investigate whether walking with PFMC and AH is more effective for promoting local trunk muscle activation than walking without PFMC and AH.
  
  
  METHODS
  Twenty healthy men (28.9 ± 3.14 years, 177.2 ± 4.25 cm, 72.1 ± 6.39 kg, body mass index 22.78 ± 2.38 kg/m2) were participated in this study. Surface electrodes were attached over the multifidus (MF), lumbar erector spinae (LES), thoracic erector spinae (TES), transverse abdominus-internal oblique abdominals (TrA-IO), external oblique abdominals (EO), and rectus abdominus (RA). The amplitudes of electromyographic signals were measured during a normal walking with and without PFMC and AH.
  
  
  RESULTS
  PFMC and AH while walking was found to result in significant bilateral increases in the normalized maximum voluntary contraction (MVC) of MFs and TrA-IOs (p< 0.05). Ratios of local muscle activity to global muscle activities were increased while performing PFMC and AH during normal walking. Bilateral TrA-IO/EO activity ratios were significantly increased by PFMC and AH (p< 0.05).
  
  
  CONCLUSIONS
  Performance of the PFMC and AH during walking resulted in significantly more recruitment of local trunk muscles. This study suggests that PFMC and AH during normal daily walking improves activation of muscles responsible for spinal dynamic stabilization and might be useful if integrated into low back disability and pain physical rehabilitation efforts.
authors.affiliation: Department of Physical Medicine and Rehabilitation, College of Medicine, Yeungnam University, Korea.
authors.forename: Ah Young
authors.initials: AY
authors.lastname: Lee
authors.affiliation: Department of Physical Medicine and Rehabilitation, College of Medicine, Yeungnam University, Korea.
authors.forename: Seung Ok
authors.initials: SO
authors.lastname: Baek
authors.affiliation: Department of Physical Medicine and Rehabilitation, College of Medicine, Yeungnam University, Korea.
authors.forename: Yun Woo
authors.initials: YW
authors.lastname: Cho
authors.affiliation: Department of Biomedical Engineering, The University of Iowa, Iowa city, IA, USA.
authors.forename: Tae Hong
authors.initials: TH
authors.lastname: Lim
authors.affiliation: Department of Anesthesiology, University of Kansas School of Medicine-Wichita, Kansas Spine Institute, Wichita, KS, USA.
authors.forename: Rodney
authors.initials: R
authors.lastname: Jones
authors.affiliation: Department of Physical Medicine and Rehabilitation, College of Medicine, Yeungnam University, Korea.|Biomedical Engineering Institute, Yeungnam University, Korea.|Medical Devices Clinical Trial Center, Yeungnam University, Korea.
authors.forename: Sang Ho
authors.initials: SH
authors.lastname: Ahn
mesh_terms: D000009:Abdominal Muscles / Q000502:physiology; D000328:Adult; D004576:Electromyography; D015444:Exercise / Q000502:physiology; D005081:Exercise Therapy / Q000379:methods*; D064368:Healthy Volunteers; D006801:Humans; D017116:Low Back Pain / Q000503:physiopathology / Q000534:rehabilitation*; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000503:physiopathology*; D064170:Paraspinal Muscles / Q000503:physiopathology*; D017773:Pelvic Floor / Q000503:physiopathology*; D016138:Walking / Q000502:physiology*
keywords: Pelvic floor muscle contraction; abdominal hollowing; internal oblique abdominals; local trunk muscle activation; multifidus; surface electromyography; transverse abdominus; walking