Skip to main content
OpenTrials
Recruiting

NCT Number: NCT06985420

The Effect of the Menstrual Cycle on Immune Cell Activity and Recovery After Resistance Exercise

The goal of this observational study is to learn how the menstrual cycle affects immune cell activation, recruitment, and recovery responses after resistance exercise in healthy, resistance-trained women aged 18-40. The main questions it aims to answer are:

Does the menstrual cycle influence neutrophil recruitment and adhesion after resistance exercise? Does the menstrual cycle affect markers of muscle damage and functional recovery? Researchers will compare three menstrual phases (early follicular, late follicular, and mid-luteal) to see if immune responses and recovery outcomes differ across these phases.

Participants will:

Complete resistance exercise protocols across three different menstrual cycle phases.

Provide blood samples to assess immune cell activation and muscle damage markers.

Track sleep, mood, and recovery with questionnaires and wear an accelerometer.

Recruiting

Interested in participating?

Request Info

Key information

Conditions

Healthy Women Menstruation Resistance Exercise

Age range

18 year–40 year

Sex eligibility

Female

Study type

Observational

Primary location

University of Central Florida

Orlando, Florida, 32816, United States

Location status: Recruiting

Location contact

Jessica M Moon

CONTACT

[email protected]

407-823-0623

Jessica M Moon

PRINCIPAL_INVESTIGATOR

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Women between the ages of 18 and 40.
  • Must weigh at least 110 pounds.
  • Healthy as determined by medical history, physical activity readiness, and menstrual cycle questionnaires.
  • Actively resistance training for at least 6 months (minimum of 3 resistance training sessions per week, with at least one lower body session).
  • Pre-menopausal and have a regular menstrual cycle (eumenorrheic), with a clear start of menses (early follicular phase).
  • Not currently pregnant or planning to become pregnant during the study.
  • Have not used hormonal birth control or intrauterine devices in the past 3 months (or three full menstrual cycles).
  • Able to recall approximate start dates of their last 6 menstrual cycles.
  • Willing to follow study instructions, including avoiding exercise, alcohol, and caffeine before testing visits.
  • Free from previous or current lower body injuries that could limit performance.
  • Not regularly taking any medications that could interfere with the study.
  • Determined to have a high likelihood of successful blood draws by a certified phlebotomist.

Exclusion criteria

  • Do not give consent to participate.
  • Have been determined unfit to participate based on medical or activity history (using health questionnaires).
  • Currently take prescription or over-the-counter medication that could affect the study results.
  • Have a chronic illness requiring medical care.
  • Not currently resistance-trained (don't meet the exercise requirement).
  • Pregnant or planning to become pregnant during the study.
  • Do not have regular periods or have been diagnosed as amenorrhoeic (absence of menstruation).
  • Currently taking any performance-enhancing drugs.
  • Currently using hormonal birth control or intrauterine devices (IUDs), or have used them in the past three months (or three full menstrual cycles).
  • Determined unlikely to have a successful blood draw by a trained phlebotomist.
  • Weigh less than 110 pounds.

Treatment and study plan

Resistance Exercise

Other

Resistance Exercise Protocols: Participants will perform exercises, including belt squats, hex bar deadlifts, and plyometric drop jumps. The load and intensity will be standardized based on each participant's 1-repetition maximum (1RM) to ensure uniformity across trials.

Menstrual Cycle Phases

Other

Menstrual Cycle Phases: The key exposure variable is the phase of the menstrual cycle, with participants being assessed during the early follicular, late follicular, and mid-luteal phases.

Primary outcomes

  1. Neutrophil Recruitment and Adhesion Dynamics

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Neutrophil cell index (impedance reflecting neutrophil migration) using Real-Time Cell Analysis (RTCA). Objective: To assess the differences in neutrophil recruitment and adhesion across menstrual cycle phases (early follicular, late follicular, and mid-luteal).

    Time Frame: Assessed at 2 time points (baseline and 4 hours post exercise) on 3 experimental trial days (1 per menstrual cycle; up to 4 cycles per participant, over approximately 16 weeks).

  2. Systemic Concentrations of CXCL8

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Plasma levels of CXCL8 (interleukin-8). Objective: To evaluate if menstrual cycle phases influence systemic chemokine levels in response to exercise.

    Time Frame: Collected at 2 time points (baseline and 4 hours post exercise) on 3 experimental trial days (1 per menstrual cycle; up to 4 cycles per participant, over approximately 16 weeks).

  3. Muscle Function and Recovery- Active Range of Motion

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Changes in active range of motion (AROM). Objective: To examine the impact of the menstrual cycle on functional recovery following resistance exercise.

    Time Frame: Assessed at 5 time points (baseline, immediately post-exercise, 4 hours post, 24 hours post, and 48 hours post) on 3 experimental trial days (1 per menstrual cycle; up to 4 cycles per participant, over approximately 16 weeks).

  4. Muscle Function and Recovery- Pain Pressure Threshold

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Changes in pain pressure threshold (PPT). Objective: To examine the impact of the menstrual cycle on functional recovery following resistance exercise.

    Time Frame: Assessed at 5 time points (baseline, immediately post-exercise, 4 hours post, 24 hours post, and 48 hours post) on 3 experimental trial days (1 per menstrual cycle; up to 4 cycles per participant, over approximately 16 weeks).

  5. Muscle Function and Recovery - Countermovement Jump

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Changes in countermovement jump (CMJ) height. Objective: To examine the impact of the menstrual cycle on functional recovery following resistance exercise.

    Time Frame: Assessed at 5 time points (baseline, immediately post-exercise, 4 hours post, 24 hours post, and 48 hours post) on 3 experimental trial days (1 per menstrual cycle; up to 4 cycles per participant, over approximately 16 weeks).

  6. Muscle Function and Recovery - Maximal Voluntary Isometric Contraction

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Changes in maximal voluntary isometric contraction (MVIC). Objective: To examine the impact of the menstrual cycle on functional recovery following resistance exercise.

    Time Frame: Assessed at 5 time points (baseline, immediately post-exercise, 4 hours post, 24 hours post, and 48 hours post) on 3 experimental trial days (1 per menstrual cycle; up to 4 cycles per participant, over approximately 16 weeks).

Secondary outcomes

  1. Systemic Concentrations of Myoglobin

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Plasma levels of myoglobin (MYB). Objective: To determine how menstrual cycle phases affect muscle damage/inflammation markers after resistance exercise.

    Time Frame: Collected at 5 time points (baseline, immediately post-exercise, 4 hours post, 24 hours post, and 48 hours post) on 3 experimental trial days per participant (approximately 16 weeks total).

  2. Systemic Concentrations of Creatine kinase

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Plasma levels of creatine kinase (CK). Objective: To determine how menstrual cycle phases affect muscle damage/inflammation markers after resistance exercise.

    Time Frame: Collected at 5 time points (baseline, immediately post-exercise, 4 hours post, 24 hours post, and 48 hours post) on 3 experimental trial days per participant (approximately 16 weeks total).

  3. Systemic Concentrations of C-Reactive Protein

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Plasma levels of C-reactive protein (CRP). Objective: To determine how menstrual cycle phases affect muscle damage/inflammation markers after resistance exercise.

    Time Frame: Collected at 5 time points (baseline, immediately post-exercise, 4 hours post, 24 hours post, and 48 hours post) on 3 experimental trial days per participant (approximately 16 weeks total).

  4. Subjective Measures of Perceived Recovery

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Perceived Recovery Status Scale score. Objective: To assess perceived recovery and performance across menstrual cycle phases.

    Time Frame: Assessed at 5 time points (baseline, immediately post, 4 hours, 24 hours, and 48 hours post-exercise) on up to 3 experimental trial days (approximately 16 weeks total).

  5. Subjective Measures of Perceived Recovery

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Visual Analog Scale (VAS) ratings for recovery. Objective: To assess perceived recovery across menstrual cycle phases.

    Time Frame: Assessed at 5 time points (baseline, immediately post-exercise, 4 hours post, 24 hours post, and 48 hours post) on up to 4 experimental trial days per participant (approximately 16 weeks total).

  6. Subjective Measures of Fatigue

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Visual Analog Scale (VAS) ratings for fatigue. Objective: To assess perceived fatigue across menstrual cycle phases.

    Time Frame: Assessed at 5 time points (baseline, immediately post-exercise, 4 hours post, 24 hours post, and 48 hours post) on 3 experimental trial days per participant (approximately 16 weeks total).

  7. Subjective Measures of Soreness

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Visual Analog Scale (VAS) ratings for soreness. Objective: To assess perceived soreness across menstrual cycle phases.

    Time Frame: Assessed at 5 time points (baseline, immediately post-exercise, 4 hours post, 24 hours post, and 48 hours post) on 3 experimental trial days per participant (approximately 16 weeks total).

  8. Subjective Sleep Quality

    Time frame: Time Frame: From enrollment, through study completion, an average of 4 months.

    Measure: Groningen Sleep Quality Questionnaire (GSQQ). Objective: To investigate whether menstrual cycle phases impact subjective sleep quality.

    Time Frame: Assessed at 3 time points (baseline, 24 hours post, and 48 hours post) on 3 experimental trial days per participant (approximately 16 weeks total)

  9. Subjective Sleep Quality

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Self-Assessment of Sleep Survey (SASS-Y). Objective: To investigate whether menstrual cycle phases impact subjective sleep quality.

    Time Frame: Assessed at 1 time point (baseline) on 3 experimental trial days per participant (approximately 16 weeks total)

  10. Objective Sleep Quality

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Actigraph Accelerometer data. Objective: To investigate whether menstrual cycle phases impact objective sleep quality.

    Time Frame: Continuously monitored from 72 hours before to 48 hours after exercise on each of 3 experimental trial days (approximately 16 weeks total).

  11. Mood

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Profile of Mood States (POMS). Objective: To examine the influence of the menstrual cycle on mood during recovery from exercise.

    Time Frame: Assessed at 5 time points (baseline, immediately post-exercise, 4 hours post, 24 hours post, and 48 hours post) on 3 experimental trial days per participant (approximately 16 weeks total).

  12. Menstrual Distress

    Time frame: From enrollment, through study completion, an average of 4 months.

    Description: Measure: Menstrual Distress Questionnaire (MEDI-Q). Objective: To examine the influence of the menstrual cycle on menstrual distress reporting. Time Frame: Assessed at 1 time point (baseline) on 3 experimental trial days per participant (approximately 16 weeks total)

Other outcomes

  1. Cardiovascular Responses to Exercise

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Heart rate (beats per minute) recorded during exercise using a Polar H10 heart rate monitor. Objective: To measure the cardiovascular demand of resistance exercise and determine if it varies by menstrual phase.

    Time Frame: Continuously monitored during each exercise session on 3 experimental trial days (approximately 16 weeks total).

  2. Exercise Enjoyment

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Physical Activity Enjoyment Scale (PACES; score range 18-126, higher scores = greater enjoyment). Objective: To evaluate whether menstrual cycle phases influence exercise enjoyment.

    Time Frame: Assessed immediately post-exercise on 3 experimental trial days (approximately 16 weeks total).

  3. Rating of Perceived Exertion (RPE)

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Rating of Perceived Exertion (RPE; scale 6-20, higher = greater effort).

    Time Frame: Assessed after each exercise set and immediately post-exercise on 3 experimental trial days.

  4. Repetitions in Reserve (RIR)

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Repetitions in Reserve (RIR; reps estimated to be left in reserve). Time Frame: Assessed after each exercise set on 3 experimental trial days.

  5. Visual Analog Scale - Exercise Difficulty

    Time frame: From enrollment, through study completion, an average of 4 months.

    Measure: Visual Analog Scale (VAS; 0-100 mm, higher = more difficult). Time Frame: Assessed immediately post-exercise on 3 experimental trial days.

Study contacts

Contact information is provided by the study sponsor or research team.

Jessica M Moon

CONTACT

[email protected]

407-823-0623

Sponsors and collaborators

Lead sponsor

University of Central Florida

Other

Registry information

Official study title

The Impact of the Menstrual Cycle on Innate Immune Cell Activation, Recruitment, and Adhesion Dynamics During Recovery From Damaging Resistance Exercise: Role of Neutrophils and Systemic Chemokines.

Important dates

Study start
2024
Primary completion
2025
Study completion
2025
First posted
May 22, 2025
Registry last updated
May 22, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.