title: An electrical muscle stimulation suit for increasing blood pressure.
abstract: BACKGROUND
  Electrical muscle stimulation (EMS) is used to strengthen muscles in rehabilitation of patients and for training of athletes. Voluntary muscle straining and an inflated anti-G suit increase the arterial blood pressure (BP) and give a pilot G protection during increased +Gz. This study's aim was to measure whether BP also increases with EMS of lower body muscles.
  
  
  METHODS
  A suit with new cloth electrodes sewn into the garment was developed. There were 12 subjects who were tested in sitting position during 3 conditions with 10 consecutive periods of EMS, inflated anti-G suit (GS), or lower body muscle anti-G straining maneuvers (AGSM). BP was continuously measured noninvasively.
  
  
  RESULTS
  The means of the baseline systolic BP, before each of the test conditions, were 127 +/- 16, 128 +/- 1, and 145 +/- 14 mmHg for GS, AGSM, and EMS, respectively. During inflation of the GS, execution of the AGSM, and EMS, mean systolic BP during the first 10 s was 143 +/- 15, 146 +/- 13, and 150 +/- 13 mmHg, respectively, with no statistical difference between the conditions. The corresponding mean resting heart rate before each test was 57-63 bpm for all conditions. During the test periods with GS, AGSM, and EMS, heart rate was 59 +/- 11, 79 +/- 16, and 61 +/- 15 bpm, respectively, with statistical differences (P < 0.001) between AGSM and the other two conditions.
  
  
  CONCLUSIONS
  EMS created similar BP as GS and AGSM at 1 G and also had higher pre- and post-control values. Further studies are required to evaluate if this principle may be used for G protection of pilots.
authors.affiliation: Biosciences and Protection Division, USAF Research Laboratory, Brooks City-Base, TX, USA. ulf.balldin.ctr@brooks.af.mil
authors.forename: Ulf
authors.initials: U
authors.lastname: Balldin
authors.forename: Lance
authors.initials: L
authors.lastname: Annicelli
authors.forename: John
authors.initials: J
authors.lastname: Gibbons
authors.forename: James
authors.initials: J
authors.lastname: Kisner
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000502:physiology*; D004599:Electric Stimulation Therapy / Q000295:instrumentation* / Q000379:methods; D004566:Electrodes; D005260:Female; D006339:Heart Rate; D006801:Humans; D018471:Hypergravity / Q000009:adverse effects*; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D010865:Pilot Projects; D013026:Space Flight; D019442:Space Suits