title: Exercise before scuba diving ameliorates decompression-induced neutrophil activation.
abstract: BACKGROUND
  The goals of this study were to investigate the difference in responses between a scuba dive preceded by aerobic exercise (EX) and a nonexercise control dive (CON) and to further evaluate the potential relation between venous gas emboli (VGE) and microparticles (MP). We hypothesized that exercise would alter the quantity and subtype of annexin V-positive MP and VGE.
  
  
  METHODS
  Nineteen divers performed two dives to 18 m seawater for 41 min separated by at least 3 d, one of which was preceded by 60 min of treadmill interval exercise. Blood was obtained before exercise, before diving, and 15 min, 2 h, 4 h, and 24 h after surfacing. Intravascular bubbles were quantified by transthoracic echocardiography at 15, 40, 80, and 120 min.
  
  
  RESULTS
  The median VGE remained unchanged between the two dives; however, there was a significant increase in VGE in the exercise dive at 40 and 80 min at rest. MP were significantly elevated by approximately 2 times at all time points after CON compared with those after EX. Markers of neutrophil and platelet activation were elevated by both dives, and these elevations were attenuated in the EX dive.
  
  
  CONCLUSIONS
  We conclude that some of the differences observed between the EX and CON related to MP and platelet and neutrophil activation provide additional insight into the potential protective benefits of exercise; however, further study is needed to understand the mechanism and true potential of these benefits.
authors.affiliation: 1Department of Physiology, School of Medicine, University of Split, Split, CROATIA; 2Department of Emergency Medicine, University of Maryland, Baltimore, MD; and 3Institute for Environmental Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
authors.forename: Dennis
authors.initials: D
authors.lastname: Madden
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Thom
authors.forename: Tatyana N
authors.initials: TN
authors.lastname: Milovanova
authors.forename: Ming
authors.initials: M
authors.lastname: Yang
authors.forename: Veena M
authors.initials: VM
authors.lastname: Bhopale
authors.forename: Marko
authors.initials: M
authors.lastname: Ljubkovic
authors.forename: Zeljko
authors.initials: Z
authors.lastname: Dujic
mesh_terms: D000328:Adult; D055252:Cell-Derived Microparticles; D003665:Decompression Sickness / Q000276:immunology / Q000517:prevention & control*; D004242:Diving / Q000502:physiology*; D004618:Embolism, Air / Q000000981:diagnostic imaging; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D018375:Neutrophil Activation; D015539:Platelet Activation; D014463:Ultrasonography