Twelve Months of Time-restricted Eating and Resistance Training Improves Inflammatory Markers and Cardiometabolic Risk Factors

Abstract

INTRODUCTION: Recently, a modified intermittent fasting protocol was demonstrated to be able to maintain muscle mass and strength, decrease fat mass, and improve some inflammation and cardiovascular risk factors in healthy resistance-trained males after 2 months. The present study sought to investigate the long-term effects on these parameters. METHODS: The experiment was a single-blind randomized study. Twenty healthy subjects were enrolled and underwent 12 months of either a time-restricted eating (TRE) diet or a normal diet (ND) protocol, along with resistance training. In the TRE protocol, subjects consumed their energy needs in three meals during an 8-h period of time each day (1 pm, 4 pm, and 8 pm). Subjects in the ND group also had three meals, which were consumed at 8 am, 1 pm, and 8 pm. Groups were matched for kilocalories consumed and macronutrient distribution at baseline. RESULTS: After 12 months of TRE, body mass, fat mass, insulin-like growth factor 1, and testosterone were significantly lower compared with ND. Moreover, inflammatory markers (interleukin 6, interleukin 1β, and tumor necrosis factor α), insulin sensitivity (fasting glucose, insulin, and homeostatic model assessment for insulin resistance index), and lipid profile (cholesterol, HDL, and LDL) significantly improved after TRE compared with ND. Finally, subjects in TRE spontaneously decreased their daily energy intake, whereas those in ND maintained their starting kilocalories per day. No adverse events were reported. CONCLUSIONS: Our results suggest that long-term TRE combined with a resistance training program is feasible, safe, and effective in reducing inflammatory markers and risk factors related to cardiovascular and metabolic diseases.