Examining the Role of Female Endogenous Sex Hormones in Eccentric Exercise

The fluctuating concentrations of female sex hormones, namely estrogen and progesterone may have an effect on the ability of the tissue to withstand challenging exercise conditions, such as eccentric exercise. These sex hormones have also been purported to influence the perceived difficulty of exercise. This study aims to uncover how the different estrogen and progesterone concentrations present throughout the menstrual cycle effect perceived readiness to perform, perceptions of difficulty, and different recovery metrics.

Study Overview

• Status: Recruiting
• Conditions: Inflammatory Response
• Intervention / Treatment: Behavioral: Eccentric leg extension

Detailed Description

Although nearly half of the population is female, less than 10% of research resources are allocated to understanding how their dynamic physiology impacts athletic readiness, performance, and recovery. The fluctuating concentrations of female sex hormones, namely estrogen and progesterone may have an effect on the ability of the tissue to withstand challenging exercise conditions, such as eccentric exercise. This study aims to uncover how the different estrogen and progesterone concentrations present throughout the menstrual cycle effect perceived readiness to perform, perceptions of difficulty, and the inflammatory environment and quantification of muscle damage.

• Study Type: Interventional
• Enrollment (Estimated): 30
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Todd Schroeder, PhD; Phone Number: 3234422180; Email: eschroed@pt.usc.edu

Study Locations

• United States
  • California
    • Los Angeles, California, United States, 90033
      • Recruiting
      • Clinical Exercise Research Center
      • Contact: Bailey McLagan, MS; Phone Number: 323-442-2180; Email: mclagan@usc.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• 18-35 years of age
• BMI of 18.5-29.9 as a BMI below or above these cut points results in highly varied menstrual cycle lengths [15]
• Not taking contraception or other types of medication that could influence reproductive status
• Regular menstruation
• Non-pregnant
• Medically free from chronic diseases
• Novel to downhill running
• Weight greater than or equal to 110 lbs
• Not taking exogenous hormones
• Not suffering from known gynecological disease (i.e., PCOS, endometriosis, etc.) that may influence menstrual cycle regularity

Exclusion Criteria:

• Amenorrhea or oligomenorrhea
• Perimenopausal or menopausal
• Recreational or professional trail or downhill runner
• On a form of contraception
• Cardiac disability
• Pacemaker
• Arterial disease
• Uncontrolled hemorrhage
• Blood clots
• Pregnant or trying to become pregnant
• Cancerous lesions
• Sensory or mental impairment
• Unstable fractures
• Weight less than 110 lbs
• Suffering from gynecological disease (i.e., PCOS, endometriosis, etc.) that may influence menstrual cycle regularity
• Taking exogenous hormones

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Health Services Research
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Low estrogen; low progesterone; Participants will come in while on their period. During this time estrogen and progesterone concentrations are low.	Behavioral: Eccentric leg extension; Participants will complete a 10 x 10 eccentric leg extension on a Cybex Norm dynamometer. Upon arrival, participants will be asked their perceived readiness to perform on a 11 point numeric rating scale. Before the running protocol a baseline blood sample will be collected, as well as passive and active delayed onset muscle soreness (DOMS), a countermovement jump. Half way through each set (i.e., after the 5th repetition) participants will be asked to rank their level of difficulty on a 11 point OMNI Res scale. This will occur during each set. Participants will have follow up blood draws, measures of muscle function (i.e, jump height) and soreness measured immediately after and 24 and 48 hours post-exercise.
Experimental: High estrogen; low progesterone; Participants will come in just before ovulation, when estrogen concentrations are high and progesterone concentrations remain low.	Behavioral: Eccentric leg extension; Participants will complete a 10 x 10 eccentric leg extension on a Cybex Norm dynamometer. Upon arrival, participants will be asked their perceived readiness to perform on a 11 point numeric rating scale. Before the running protocol a baseline blood sample will be collected, as well as passive and active delayed onset muscle soreness (DOMS), a countermovement jump. Half way through each set (i.e., after the 5th repetition) participants will be asked to rank their level of difficulty on a 11 point OMNI Res scale. This will occur during each set. Participants will have follow up blood draws, measures of muscle function (i.e, jump height) and soreness measured immediately after and 24 and 48 hours post-exercise.
Experimental: Medium estrogen; high progesterone; Participants will come in just after ovulation when estrogen concentrations are at a medium level, and progesterone concentrations are high.	Behavioral: Eccentric leg extension; Participants will complete a 10 x 10 eccentric leg extension on a Cybex Norm dynamometer. Upon arrival, participants will be asked their perceived readiness to perform on a 11 point numeric rating scale. Before the running protocol a baseline blood sample will be collected, as well as passive and active delayed onset muscle soreness (DOMS), a countermovement jump. Half way through each set (i.e., after the 5th repetition) participants will be asked to rank their level of difficulty on a 11 point OMNI Res scale. This will occur during each set. Participants will have follow up blood draws, measures of muscle function (i.e, jump height) and soreness measured immediately after and 24 and 48 hours post-exercise.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Counter movement jump height	A countermovement jump (CMJ) will be performed on VALD ForceDecks to determine muscle function overtime.	Change over time (pre/post, 24 hour, 48 hour)
Passive Delayed Onset Muscle Soreness (DOMS)	DOMS will be assessed as participants are stationary to assess their perception of muscle damage over time.	Change over time (pre/post, 24 hour, 48 hour)
Active Delayed Onset Muscle Soreness (DOMS)	DOMS will be assessed as participants complete a wall sit to assess their perception of muscle soreness over time.	Change over time (pre/post, 24 hour, 48 hour)
Preparedness to perform	Perceived readiness will be measured on an 11 point numeric rating scale (NRS) with 0 being not ready at all, and 10 being most prepared	Pre exercise
Rating of difficulty	Perceived difficulty will be measured on a 11 point numeric rating scale called the OMNI res throughout the duration of exercise.	30 minutes
Inflammatory markers	Inflammatory markers (IL-6, IL-8, TNF-alpha, and IL-10) will be measured in blood serum to understand how the concentration of estrogen changes the inflammatory response to damaging exercise.	Change over time (pre/post, 24 hour, 48 hour)

Collaborators and Investigators

• Sponsor: University of Southern California

Publications and helpful links

General Publications

• Oosthuyse T, Bosch AN. The Effect of Gender and Menstrual Phase on Serum Creatine Kinase Activity and Muscle Soreness Following Downhill Running. Antioxidants (Basel). 2017 Feb 23;6(1):16. doi: 10.3390/antiox6010016.

Study record dates

Study Major Dates

• Study Start (Actual): March 7, 2025
• Primary Completion (Estimated): May 30, 2026
• Study Completion (Estimated): August 1, 2026

Study Registration Dates

• First Submitted: June 20, 2023
• First Submitted That Met QC Criteria: June 28, 2023
• First Posted (Actual): July 7, 2023

Study Record Updates

• Last Update Posted (Actual): March 25, 2026
• Last Update Submitted That Met QC Criteria: March 24, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: menstrual cycle; exercise
• Additional Relevant MeSH Terms: Behavior; Motor Activity
• Other Study ID Numbers: HS-23-00363

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No