Association of dietary and lifestyle inflammation scores with muscle strength and muscle endurance among Tehranian adults

Diet and lifestyle as modifiable factors play an effective role in muscle strength and muscle endurance. In addition, inflammatory reactions may have an association with the etiology of a a lower muscle strength and muscle endurance. We aimed to investigate the association of dietary and lifestyle inflammation scores (DLIS) with muscle strength and muscle endurance in a sample of Iranian adults. In this cross-sectional study, 270 adults aged 20 to 59 years (55.9% female) were selected. The dietary intakes were collected using a 168-item semi-quantitative food frequency questionnaire. The DLIS was calculated using the dietary inflammatory score (DIS), and lifestyle inflammatory score (LIS). Muscle endurance and muscle strength were measured by a digital-handgrip-dynamometer. Multivariate adjusted means for muscle strength and endurance across quartiles of the DIS, LIS, and DLIS were determined by the ANCOVA test. Multiple linear regression analysis was used to evaluate the association between inflammation scores (i.e., DIS, LIS, and DLIS), and muscle strength, muscle endurance. The DLIS ranged between −2.94 and 3.09. The adjusted P-value of muscle strength of the right hand (MSR) along quartiles of DIS was significantly lower (P = 0.024). MSR (β: −1.19; P-value: 0.020) and mean muscle strength (MMS) (β: −0.95; P-value: 0.047) had significant association with DIS. MSR (β: −0.85; P-value: 0.050) had a marginally significant association with DLIS. Overall, we found that a high adherence to a pro-inflammatory diet might be associated to a lower muscle strength. However, a lifestyle with greater inflammatory potential was not related to any components of muscle endurance. Further studies with prospective designs are needed to confirm the present findings in further details.