Researcher ORCID Identifier

Graduation Year


Date of Submission


Document Type

Open Access Senior Thesis

Degree Name

Bachelor of Arts


W.M. Keck Science Department

Reader 1

Jenna Monroy

Reader 2

Lars Schmitz

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Terms of Use for work posted in Scholarship@Claremont.

Rights Information

2023 Natalie D Bitetti


Background: Cortisol plays a central role in both muscle breakdown and growth. These effects are highly dependent on dose and interactions with other hormones. It is known that men and women show considerable differences in their muscle structure and physiology, which are largely driven by hormonal differences. Cortisol release patterns may also vary between the sexes, with current research showing considerable disagreement. The interplay between cortisol and muscle, two highly variable and sexually dimorphic factors, may prove to have different effects in males versus females.

Objective: This meta-analysis integrates existing research on sex differences in cortisol-muscle physiology with existing research on cortisol’s effects on muscle (Figure 1). By connecting this triangle, I examine sexually dimorphic effects of cortisol on muscle.

Methods: 10 papers were selected for data analysis after thorough screening for keywords, age, and necessary data. Data for baseline cortisol, stressor cortisol, muscle cross-sectional area (CSA), and fiber type proportion were extracted, and subjected to unpaired t-test or linear regression analysis.

Results: Women showed a pattern of higher baseline cortisol, while men showed a pattern of a larger cortisol response to the physical stressor. Men showed no significant correlation between CSA and cortisol. There was a trend of increasing type I fibers and decreasing type II fibers correlated with cortisol levels in men. This meta-analysis highlighted potential relationships between cortisol and muscle characteristics, and revealed deficits in existing data on women in this area.