Long-term aerobic exercise and omega-3 supplementation modulate osteoporosis through inflammatory mechanisms in post-menopausal women: a randomized, repeated measures study

Background: Evidence indicates that dietary fats and physical activity influence bone health. The purpose of this study was to examine the effects of long-term aerobic exercise and omega-3 (N-3) supplementation on serum inflammatory markers, bone mineral density (BMD), and bone biomarkers in post-menopausal women. Methods: Seventy-nine healthy sedentary post-menopausal women aged 58-78 years participated in this study. Subjects were randomized to one of 4 groups: exercise + supplement (E+S, n = 21), exercise (E, n = 20), supplement (S, n = 20), and control (Con, n = 18) groups. The subjects in the E+S and E groups performed aerobic exercise training (walking and jogging) up to 65% of HRmax, three times a week for 24 weeks. Subjects in the E+S and S groups consumed 1000 mg/d N-3 for 24 weeks. The lumbar spine (L-2-L-4) and femoral neck BMD, serum tumor necrosis factor (TNF) alpha, interleukin (IL) 6, prostaglandin (PG) E-2, estrogen, osteocalcin, 1, 25-dihydroxyvitamin D-3 (1, 25 Vit D), C-telopeptide (CTX), parathyroid hormone (PTH) and calcitonin (CT) were measured at baseline, the end of week 12 and 24. Results: Serum estrogen, osteocalcin, 1, 25 Vit D, CT, L-2-L-4 and femoral neck BMD measures increased (P < 0.05) and the serum CTX, PTH, TNF-alpha, IL-6, and PGE(2) decreased (P < 0.05) in E + S group after the 24 wk intervention but not in the E or S intervention groups. L-2-L-4 and femoral neck BMD, estrogen, osteocalcin, and CT were negatively (P < 0.05) correlated with TNF-alpha and PGE(2). PTH and CT were correlated positively and negatively with IL-6, respectively (P < 0.05). Conclusions: The present study demonstrates that long-term aerobic exercise training plus N-3 supplementation have a synergistic effect in attenuating inflammation and augmenting BMD in post-menopausal osteoporosis.