title: On the significance of magnesium in extreme physical stress.
abstract: In a double-blind randomized study, 23 competitive triathletes competing in an event consisting of a 500-meter swim, a 20-km bicycle race, and a 5-km run were studied after 4-week supplementation with placebo or 17 mmol/d Mg orotate. The tests were carried out without a break. Blood was collected before and after the test, and between the different events for assaying energy stress and membrane metabolism. Swimming, cycling, and running times decreased in the Mg-orotate group compared with the controls. Serum glucose concentration increased 87% during the test in the control group and 118% in the Mg-orotate group, while serum insulin increased 39% in the controls and decreased 65% in the Mg-orotate group. Venous O2 partial pressure increased 126% during the test in the controls and increased 208% in the Mg-orotate group. Venous CO2 partial pressure after the bicycle race decreased 66% (significantly) in the Mg-orotate group compared with 74% in the controls. Blood proton concentration decreased to 90% in the Mg-orotate group (significantly) compared with 98% in the controls. Blood leukocyte count increased from 5.92/nL to 11.0/nL in the controls and from 5.81/nL to 9.10/nL in the Mg-orotate group, a significant difference. Serum cortisol was lower in the Mg-orotate group before and after the test compared with the controls. CK catalytic concentration after the test was elevated 140% in the controls compared with 122% Mg-orotate group. The stress-induced modifications of energy and hormone metabolism described in this study indicate altered glucose utilization after Mg-Orotate supplementation and a reduced stress response without affecting competitive potential.
authors.affiliation: Institute of Clinical Chemistry and Pathobiochemistry, University Medical School, Justus-Liebig-University, Giessen, Germany.
authors.forename: S W
authors.initials: SW
authors.lastname: Golf
authors.forename: S
authors.initials: S
authors.lastname: Bender
authors.forename: J
authors.initials: J
authors.lastname: Grüttner
mesh_terms: D000328:Adult; D001642:Bicycling / Q000502:physiology; D001786:Blood Glucose / Q000378:metabolism; D002245:Carbon Dioxide / Q000097:blood; D002302:Cardiac Output / Q000187:drug effects; D004311:Double-Blind Method; D004734:Energy Metabolism / Q000187:drug effects; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007958:Leukocyte Count; D008297:Male; D009963:Orotic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D012420:Running / Q000502:physiology; D013177:Sports / Q000502:physiology*; D013312:Stress, Physiological / Q000378:metabolism / Q000503:physiopathology*; D013550:Swimming / Q000502:physiology
chemical_list: D001786:Blood Glucose; D002245:Carbon Dioxide; D009963:Orotic Acid; C104468:magnesium orotate; D006854:Hydrocortisone