title: The effect of pre-dive ingestion of dark chocolate on endothelial function after a scuba dive.
abstract: OBJECTIVE
  The aim of the study was to observe the effects of dark chocolate on endothelial function after scuba diving.
  
  
  METHODS
  Forty-two male scuba divers were divided into two groups: a control (n=21) and a chocolate group (n=21). They performed a 33-metres deep scuba-air dive for 20 minutes in a diving pool (Nemo 33, Brussels). Water temperature was 33⁰C. The chocolate group ingested 30 g of dark chocolate (86% cocoa) 90 minutes before the dive. Flow-mediated dilatation (FMD), digital photoplethysmography and nitric oxide (NO) and peroxynitrites (ONOO-) levels were measured before and after the scuba dive in both groups.
  
  
  RESULTS
  A significant decrease in FMD was observed in the control group after the dive (91±7% (mean±95% confidence interval) of pre-dive values; P<0.001) while it was increased in the chocolate group (105±5% of pre-dive values; P<0.001). No difference in digital photoplethysmography was observed between before and after the dives. No variation of circulating NO level was observed in the control group whereas an increase was shown in the chocolate group (154±73% of pre-dive values; P=0.04). A significant reduction in ONOO- was observed in the control group (84±12% of pre-dive values; P=0.003) whereas no variation was shown after the dive with chocolate intake (100±28% of pre-dive values; ns).
  
  
  CONCLUSIONS
  Ingestion of 30 g of dark chocolate 90 minutes before scuba diving prevented post-dive endothelial dysfunction, as the antioxidants contained in dark chocolate probably scavenge free radicals.
authors.affiliation: Université de Bretagne Occidentale, UFR Sciences et Techniques, Brest, Environmental, Occupational and Aging Physiology Department, Haute Ecole Paul Henri Spaak - ISEK, 91 Av C Schaller, B 1160 Brussels, Belgium, Phone: +32-(0)2-660-2027, Fax: +32-(0)2-660-0334, E-mail: theunissen@he-spaak.be.
authors.forename: Sigrid
authors.initials: S
authors.lastname: Theunissen
authors.affiliation: Haute Ecole Paul-Henri Spaak, Environmental and Occupational and Aging Physiology Laboratory, DAN Europe Research, Brussels, Belgium.
authors.forename: Costantino
authors.initials: C
authors.lastname: Balestra
authors.affiliation: Haute Ecole Paul-Henri Spaak, Environmental and Occupational and Aging Physiology Laboratory, Brussels, Belgium.
authors.forename: Antoine
authors.initials: A
authors.lastname: Boutros
authors.affiliation: Brugmann University Hospital, Department of Intensive Care Medicine, Brussels, Belgium.
authors.forename: David
authors.initials: D
authors.lastname: De Bels
authors.affiliation: Université de Bretagne Occidentale, UFR Sciences et Techniques, Brest.
authors.forename: François
authors.initials: F
authors.lastname: Guerrero
authors.affiliation: Center for Hyperbaric Oxygen Therapy, Military Hospital Queen Astrid, Brussels, Belgium.
authors.forename: Peter
authors.initials: P
authors.lastname: Germonpré
mesh_terms: D000328:Adult; D000975:Antioxidants; D015415:Biomarkers / Q000097:blood; D001916:Brachial Artery / Q000502:physiology; D002099:Cacao / Q000737:chemistry; D016022:Case-Control Studies; D004242:Diving / Q000502:physiology*; D004435:Eating; D004730:Endothelium, Vascular / Q000502:physiology*; D006801:Humans; D008297:Male; D008833:Microcirculation / Q000502:physiology; D009569:Nitric Oxide / Q000097:blood; D018384:Oxidative Stress; D030421:Peroxynitrous Acid / Q000097:blood; D017156:Photoplethysmography; D063177:Pulse Wave Analysis; D018709:Statistics, Nonparametric; D013997:Time Factors; D059289:Vascular Stiffness / Q000502:physiology
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D030421:Peroxynitrous Acid; D009569:Nitric Oxide
keywords: Antioxidants; cardiovascular; circulation; diving research; hyperoxia; nitric oxide; scuba