Feasibility and acceptability of 8-h time-restricted eating combined with aerobic or resistance training in older adults with prediabetes and obesity.

Background: Obesity and prediabetes in older adults are typically treated with weight management and exercise. Time-restricted eating (TRE), shortening the daily eating window, combined with aerobic training (AT) or resistance training (RT), may help reduce fat mass, preserve lean mass, and decrease cardiometabolic risk.

Purpose: This pilot study was conducted to assess the feasibility and acceptability of 8-h TRE combined with AT or RT in older adults with prediabetes and obesity.

Design: We implemented a 12-week two-arm randomized trial of a self-selected 8-h TRE window (10 AM-6 PM, 11 AM-7 PM, or 12-8 PM) combined with either AT or RT.

Methods: Thirty-four participants were randomized to TRE-AT (n = 19) or TRE-RT (n = 15). Data on feasibility (recruitment rate), acceptability (study visit attendance, missing data, and attrition), and adherence (eating window, exercise days, and exercise prescription) were collected, and exploratory measures, including body weight, body composition, dietary intake, and biomarkers, were assessed.

Results: Seventy-three percent of the TRE-AT group and 80% of the TRE-RT group completed the trial. Participants in both groups adhered to the 8-h TRE window ∼75% of the time (5.8 days/week) and attended ∼95% of weekly TRE intervention meetings. Participants exercised 81% (TRE-AT) and 88% (TRE-RT) of the days prescribed but adhered to the assigned protocol only 67%-68% of the time. No differences in feasibility or acceptability were found between groups. Only the TRE-AT group showed significant reductions in body weight and BMI from baseline.

Conclusions: Eight-hour TRE with AT or RT is feasible and acceptable in older adults with prediabetes and obesity. Future trials should focus on enhancing participant engagement and adherence.

Clinical trial registration number: Clinicaltrials.gov NCT05290233.