NATURAL SPORTING ABILITY AND PREDISPOSITION TO CARDIOVASCULAR DISORDERS

We tested the hypothesis that people with a natural ability in 'power sports' (a presumed marker for predominance of type 2, glycolytic musc le fibres) might have increased risks of coronary heart disease (CHD) compared to those with a natural ability in 'endurance sports' (as a m arker for predominance of type 1, oxidative muscle fibres). We examine d subsequent cardiovascular disorders retrospectively in 231 male form er soldiers, aged 34-87 years, who had undergone a course in physical training in the Army School of Physical Training, Aldershot, UK, who a ssessed themselves as having natural ability in either power (n=107) o r endurance (n=124) sports. The proportion with CHD, defined as angina and/or coronary angioplasty and/or coronary artery bypass graft and/o r heart attack was 18.7% in the 'power group' vs. 9.7% in the 'enduran ce group' (difference: chi(2) = 3.9, p = 0.05). The proportions with C HD and/or risk factors rose to 39.3% in the 'power group' vs. 25.8% in the 'endurance group' (difference: chi(2) = 4.8, p = 0.03). Under log istic regression analysis, compared to the 'endurance group', the 'pow er group' had 2.2 (95% CI: 1.00-4.63) the risk of developing CHD, and 1.86 (95% confidence interval: 1.06 to 3.25) the risk of developing CH D and/or risk factors. Men with a natural ability in 'power sports' av e at increased risk of developing cardiovascular disorders, compared t o men with a natural ability in 'endurance sports'. A predominance of type 2, glycolytic muscle fibres, presumably of genetic origin, may pr edispose to cardiovascular disorders.