An interventional study of protein supplement and Placebo in Muscle Atrophy, sponsored by Sam Houston State University. Recruiting at 2 sites in United States. Open to female participants aged 18 Years to 35 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-09-25.
Sponsored by Sam Houston State University · Not applicable, Interventional, and Treatment
The purpose of this research is to determine if increasing 12% of daily protein intake during the luteal phase mitigates the potential catabolic effects of progesterone on skeletal muscle. We anticipate there will be an advantageous, decreased catabolic effect with increasing protein intake during the luteal phase.
By doing this study, we hope to learn if millions of women would benefit from additional protein supplementation during the luteal phase, which may lead to decreased skeletal muscle atrophy over time. Your participation in this research will last about 4 months.
The physiologic effects of the female menstrual cycle have been shown to cause many changes to metabolic processes throughout the body depending on the phase of the cycle. For example, during the follicular phase, increase in estrogen aids in arterial vasodilation, lipid metabolism, neuroprotection, and maintaining bone density (Gruber et al. 2002). During the luteal phase, the increase in progesterone aids in thermoregulation, increased respiration, and basal insulin levels (Taraborrelli 2015). However, there is conflicting evidence regarding net progesterone effects on skeletal muscle. Some studies state that progesterone has an anabolic effect while others suggest the contrary. Despite the discrepancies with current literature, Sims et al. recommends female athletes increase their protein intake by 12% during the luteal phase of their menstrual cycle to potentially counteract the protein catabolic effects of progesterone on skeletal muscle (2023). The basis of this conclusion was based on invitro and in vivo studies showing decreases amino acids during the luteal phase (Faustmann et al. 2018 \& Draper et al. 2018)
To our knowledge, no study exists that analyzes protein degradation with protein supplementation increase during the luteal phase. The purpose of this research is to determine if increasing 12% of daily protein intake during the luteal phase mitigates the potential catabolic effects of progesterone on skeletal muscle. This research could help determine if millions of women would benefit from additional protein supplementation during the luteal phase, which may lead to decreased skeletal muscle atrophy over time. We anticipate there will be an advantageous, decreased catabolic effect with increasing protein intake during the luteal phase.
Exclusion Criteria:
Will receive protein supplement
Dietary Supplement: protein supplement
Will receive placebo supplement
Dietary Supplement: Placebo
Protein supplementation during progesterone peak to stop protein degradation effect.
Also known as: A
Will receive placebo supplementation
Also known as: B
Skeletal Muscle Protein Degradation
Primary outcomes will be changes in urinary N-fragment of titin and serum 3-methylhistidine between supplementation and placebo conditions. Paired t-tests or linear mixed-effects models will be used to account for within-subject crossover effects. Hormone levels will be included as covariates. Statistical significance will be set at p \< 0.05.
Time frame: 48 hours
Decrease protein degradation
We would like to home in on protein intake and degradation to quantify the amount of protein loss seen during the luteal phase, the point at which protein degradation is deemed to be the highest. Our specific aims for this project will be to 1) quantify protein degradation at the time of the luteal phase and 2) determine whether targeted protein supplementation during the luteal phase will reduce measured protein degradation. We anticipate there will be an advantageous, decreased catabolic effect with increasing protein intake during the luteal phase. To measure this, we will use Blood and Urine samples during the menstrual cycle. Blood Samples: Blood will be collected in serum separator tubes (SST) Serum will be analyzed using enzyme-linked immunosorbent assay (ELISA) methods to measure: 3-Methylhistidine Progesterone Urine Samples: Urine samples will be analyzed using ELISA methods to measure: N-fragment of Titin Creatin
Time frame: 48 hours
Plan to share: Undecided
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