The aim of this cross-sectional study was to compare body composition and risk factors of lifestyle-related diseases between young and older male rowers and sedentary controls. Healthy males aged 19-73 years participated in the study, and were divided into four groups: 26 young rowers, 24 senior rowers, 23 young sedentary controls, and 22 senior sedentary controls. Total and regional lean soft tissue, fat mass, and bone mineral density were measured using dual-energy X-ray absorptiometry. The HDL-cholesterol of senior rowers (67.4 +/- 13.4 mg . dl(-1)) was significantly (P < 0.05) higher than that of senior sedentary controls (59.2 +/- 11.9 mg . dl(-1)), while HDL-cholesterol was similar in senior rowers and young rowers (66.1 +/- 10.8 mg . dl(-1)). Arm, leg, and trunk lean soft tissue mass were significantly higher in senior rowers (5.6 +/- 0.6 kg, 18.2 +/- 1.8 kg, and 27.3 +/- 3.2 kg respectively) than in senior sedentary controls (5.1 +/- 0.4 kg, 16.3 +/- 1.4 kg, and 24.6 +/- 1.7 kg respectively; P < 0.05). Bone mineral density was also significantly higher in senior rowers than in senior sedentary controls (ribs, lumbar spine, and pelvic segments; P < 0.05). We conclude that age-related increases in the risk of lifestyle-related diseases, such as osteoporosis and sarcopenia, are attenuated in male rowers. These results suggest that regular rowing exercise may have a positive influence in the prevention of lifestyle-related diseases in older Japanese people.