Preferred Name
Dillon Wells
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.
ORCID
https://orcid.org/0009-0000-1153-3775
Date of Graduation
5-2024
Semester of Graduation
Spring
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Department of Kinesiology
Advisor(s)
Jeremy D. Akers
Michelle Batista-Hesse
Ana-Laura Dengo
Christian Carter
Abstract
Objective: The objective of this study was to evaluate the effects of refeeds and diet breaks on biochemical, body composition, and resting metabolic rate (RMR) measures during an energy-restricted diet.
Methods: Resistance-trained men between the ages of 18-45 participated in an 8-week IER weight loss diet plan. Participants were randomly assigned to one of two dietary intervention groups: Group 1 received two days/week of refeeds (REF), and Group 2 received a one-week diet break every two weeks (BRK). All participants followed a standardized volume weight training protocol. Baseline and post-intervention dual-energy X-ray absorptiometry (DXA) scans and blood measures were conducted at baseline, before the final refeed or diet break, and post-intervention.
Results: The study was completed by 5 out of 10 participants (4 REF, 1 BRK). The REF group lost 3.05±1.52% body fat (BF) and gained 2.2±2.45 kg fat-free mass (FFM), whereas the BRK group lost 1% BF and gained 1.2kg of FFM. The REF group's RMR declined by an average of 104.75±105.82 kcal before the final refeed and increased by 387.25±679.37 kcal after the final refeed. In contrast, the BRK group's RMR declined by 123 kcal before the final diet break and increased by 461 kcal after the final diet break. In the REF group, there was a significant decrease in cortisol and total testosterone from baseline to post-testing, and an increase in leptin before and after the final refeed. Both groups exhibited minimal changes in blood markers at the final refeed or diet break, but they returned to baseline measures for post-testing.
Conclusion: In conclusion, this pilot study suggests that incorporating refeeds during energy restriction may have potential benefits in maintaining endocrine function and optimizing body composition changes. However, further research with larger sample sizes is warranted to validate these findings and provide a more comprehensive understanding of the effects.
Recommended Citation
Wells, Dillon, "The biochemical and metabolic impact of 8-weeks of intermittent energy restriction on resistance-trained adults: A pilot study" (2024). Masters Theses, 2020-current. 273.
https://commons.lib.jmu.edu/masters202029/273
