Effect of diet combined with exercise intervention on tumor necrosis factor α in overweight or obese groups: Based on the exercise dose-response relationship

Abstract

Background: Chronic low-grade systemic inflammation, often linked to obesity or being overweight, is associated with various complications and an increased risk of disease development. Tumor necrosis factor α (TNF-α) is a key inflammatory factor that significantly impacts various body functions. Objective: 1) To assess whether combined interventions are more effective than single interventions in combining diet and exercise. 2) To assess the effectiveness of exercise dose in different interventions on tumor necrosis factor (TNF-α) levels in obese or overweight patients. Methods: A thorough search was conducted across four electronic databases of randomized controlled trials that focus on exercise or dietary interventions for patients with obesity or overweight. This comprehensive review encompasses data collected up to August 2024. Two independent researchers conducted a thorough evaluation of the literature's quality. Network and dose-response analyses were performed using random effects models to examine the impact of diverse interventions on TNF-α. Results: A total of 19 randomized controlled trials with 1479 patients with obesity or overweight were included. The meta-analysis showed that the hypocaloric diet combined with aerobic training (HDAT) possessed the highest ranking (SMD= -1.00,95%CI -1.51 to -0.49), followed by the hypocaloric diet (HD) (SMD= -0.40,95%CI -0.89 to 0.09), hypocaloric diet combined with resistance training (HDRT) (SMD= -0.48,95%CI- 1.43 to 0.48), and aerobic training combined with resistance training (ART) (SMD= -0.18,95%CI -0.92 to 0.57). Additionally, a notable improvement in TNF-α levels was observed in individuals adhering to a hypocaloric diet in conjunction with exercise when the cumulative exercise volume reached 150 metabolic equivalent of task minutes per week. Conclusion: Based on the GRADE rating guidelines, moderate-quality research evidence indicates that a hypocaloric diet combined with aerobic training (HDAT) is the most effective intervention for enhancing tumor TNF-α levels in individuals with obesity or overweight. Additionally, the dose-response relationship was observed between the total exercise dose and TNF-α levels. Future research should investigate the specific effects of various aerobic exercise modalities on TNF-α levels in obese or overweight patients to develop a more personalized approach to exercise prescription