Synergistic Effects of Combined Concurrent Training and Eri-Polyunsaturated Fatty Acid Supplementation on Bone Mineral Density, Muscle Strength, and Inflammation.

Obesity has been associated with lower bone mineral density (BMD) and rapid muscle weakness. Regular exercise and polyunsaturated fatty acid (PUFA) consumption have been recognized as nonpharmaceutical approaches to increase BMD and ameliorate muscle weakness. This study aimed to determine the effects of concurrent training (CCT) and Eri-PUFA supplementation on BMD, muscular strength, and inflammation in obese adults. A total of 33 obese participants were randomly assigned to one of three groups (n=11 per group): (1) a placebo group; (2) an Eri-PUFA ingestion group (ERI); or (3) a CCT and Eri-PUFA ingestion group (CCT+ERI). The ERI and CCT+ERI groups received approximately 2.5 g of linolenic acid per day from Eri silkworm pupae. The exercise program included aerobic and resistance exercises performed under supervision three times per week for 8 weeks. Before and after the 8-week intervention, BMD, muscular strength, and inflammatory markers were measured. Only the CCT+ERI group showed a significant increase in lumbar spine BMD (5.1%, P<0.01) and upper-body muscle strength (16.9%, P<0.01) after the intervention, with differences between the groups. After the intervention, both the ERI and CCT+ERI groups showed a significant decrease in the monocyte-to-lymphocyte ratio (-25%, P<0.01 and -21.4%, P<0.05, respectively) and tumor necrosis factor-alpha (-21.6%, P<0.05 and -19.4%, P<0.05, respectively). These findings demonstrate that combining CCT and Eri-PUFA supplementation increases BMD and upper-body muscular strength and decreases inflammation. Although Eri-PUFA consumption did not affect BMD or muscle strength directly, it may have an additive effect on BMD by reducing inflammation.