Relation of running distance to plasma HDL-cholesterol level in middle-aged male runners

This study examined the relation of training distance to plasma high density lipoprotein cholesterol (HDLC) concentration in runners. Forty-eight male endurance runners, aged from 30 to 57 years, were classified into three groups according to training distance (Grade I: n = 12, 30 km/week; Grade II: n = 22, 60 km/week; Grade III: n = 14, 100 km/week in average running distance), with 12 non-lean and 12 lean subjects as age-matched untrained controls. There were no significant differences in plasma total cholesterol among the groups (194-208 mg/dl on average). HDLC level was significantly higher in the untrained, lean group than in the untrained, non-lean men (63 +/- 13 vs. 46 +/- 8 mg/dl, mean +/- SD). HDLC levels in all the runner groups were significantly higher than in untrained, lean subjects, and no differences were observed among Grade I, II and III runner groups (76 +/- 15, 76 +/- 13, 77 +/- 11 mg/dl, respectively). This study suggests that further increases in HDLC could not occur in response to further elevation of training distance in well-trained runners.