Electronic Theses and Dissertations

Date of Award


Document Type


Degree Name

Ph.D. in Nutrition and Hospitality Management

First Advisor

Nadeeja Wijayatunga

Second Advisor

Melinda Valliant

Third Advisor

Georgianna Mann

Relational Format



Time-restricted eating (TRE) is a form of intermittent fasting where calorie consumption is restricted to a time window ranging from 4 to 10 hours. A systematic review and a meta-analysis were performed to further explore the role of TRE when combined with exercise on body composition. Past literature published between 2011 and 2023 was searched. Fifteen articles, including 338 participants were analyzed. A random-effects model was used to calculate weighted mean effect sizes (ES) with 95% confidence intervals. (95% CI). There were small but significant mean reductions in FM (ES = -0.20, 95% CI = -0.28 to -0.13, and p < 0.001) and BF% (ES = -0.23, 95% CI = -0.35 to -0.11 and p < 0.001) following TRE with exercise compared to exercise only control group. However, no significant change in FFM was observed. Age, BMI, exercise type, study duration, and energy intake, did not explain the variation in ESs for FM, BF%, and FFM (p > 0.05). According to the present meta-analysis, TRE may cause a small reduction in FM and BF% while preserving FFM in adults who are also engaging in an exercise program compared to exercise-matched individuals who did not follow TRE.

A randomized controlled was conducted to determine the effects of a 6-week early TRE (eTRE) on muscle performance, body composition, sleep quality, energy/ macronutrient intake, hunger, and satiety in resistance-trained, healthy adults. Thirty-eight healthy resistance training adults were randomized to either the intervention group (INT, n = 19) who followed eTRE or to the control group (CON, n = 19) who continued their usual feeding patterns without restricting eating times. All continued their usual resistance training. Pre- and post-intervention data were collected for muscle performance via barbell bench/squat 1 rep max (1RM) and muscle endurance test. Body composition was measured using a bioelectrical impedance analyzer. Sleep quality, hunger satiety and 24-hour diet recall were assessed using the Pittsburgh Sleep Quality Index, visual analog scales, and the Automated Self-Administered 24-Hour Dietary Assessment Tool (ASA24), respectively. Two-way repeated measure ANOVA was performed. There were no significant group-by-time interactions for muscle performance (bench/squat 1RM and muscle endurance), FFM, or total energy intake (p > 0.05). While there was a significant group-by-time interaction for both FM and body fat percentage (BF%), only BF% significantly decreased pre-to post-intervention in the TRE group (p=0.008). No significant group-by-time interactions were observed for macronutrients, sleep quality, or hunger/satiety. Study feasibility measurements were explored and the overall adherence to eTRE was 76%. In conclusion, 6 weeks of eTRE may not cause significant changes in muscle performance (1RM and muscle endurance) or FFM but may cause a small reduction in BF% in resistance-trained healthy adults. However, longer-term, and large-scale studies are needed in various populations to confirm these findings.

Available for download on Friday, January 31, 2025