Resistance Training During Menstrual Cycle for Women's Health

(MCPBT Trial)

Overseen By Stuart Phillips

Age: 18 - 65

Sex: Female

Trial Phase: Academic

Sponsor: McMaster University

Must not be taking: Hormonal contraceptives, Glucocorticoids, NSAIDs, others

Disqualifiers: Pregnancy, Neuromuscular disorders, Thrombosis, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 5

Duration: 16 weeks

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to explore how different phases of the menstrual cycle affect resistance training benefits. Researchers will compare the effects of training during various cycle phases to determine any differences in exercise outcomes. Participants will join one of four groups: consistent exercise, targeting the follicular phase, targeting the luteal phase, or no exercise. Women with regular menstrual cycles who do not use hormonal contraceptives and have not been training more than three times a week may be suitable candidates.

As an unphased study, this trial provides a unique opportunity to contribute to understanding how menstrual cycles impact fitness results.

Will I have to stop taking my current medications?

The trial requires that you stop taking any medications known to affect protein metabolism, such as glucocorticoids, non-steroidal anti-inflammatory drugs, or prescription strength acne medication. Additionally, you cannot participate if you are using hormonal contraceptives or anticoagulant medications.

What prior data suggests that this menstrual cycle phase-based training is safe for women?

Research shows that training based on different phases of the menstrual cycle can affect exercise results without raising major safety concerns for participants. Studies comparing training during the follicular and luteal phases report no negative effects or issues with tolerance. Participants typically follow regular exercise routines, adjusting according to their menstrual cycle phase.

These studies primarily focus on how exercise timing impacts muscle strength and growth, rather than safety concerns. This suggests that training based on the menstrual cycle is generally well-tolerated. However, participants should always pay attention to their bodies and consult the study team if they experience discomfort or notice unusual symptoms. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about this trial because it explores how resistance training tailored to different phases of the menstrual cycle could improve women's health. Unlike typical exercise routines, which often ignore menstrual cycle phases, this method adjusts training intensity based on whether a participant is in the follicular or luteal phase. This personalized approach might enhance workout effectiveness and overall health benefits for women, offering a more synchronized and potentially more beneficial exercise regimen.

What evidence suggests that this trial's treatments could be effective for women's health?

Studies have shown that muscle strength and high-intensity performance often peak during the follicular phase of the menstrual cycle, when estrogen levels are highest. This suggests that training during this phase might lead to better strength gains. In this trial, participants in the Follicular Based Training (FOL) arm will engage in high-volume resistance training during the follicular phase. Meanwhile, those in the Luteal Based Training (LUT) arm will focus on high-volume training during the luteal phase. Research indicates that the menstrual cycle phase might not significantly affect overall resistance training results. Some findings suggest that training during either the follicular or luteal phase can improve muscle, but the follicular phase might offer a slight advantage. Overall, focusing on the follicular phase could potentially maximize strength benefits, though both approaches have shown promise. ^{3 6 7 8 9}

Are You a Good Fit for This Trial?

This trial is for women aged 18-30 with a regular menstrual cycle, BMI of 18-35, and in good health. Participants should not be on hormonal contraceptives or smoke. They must also have exercised less than three times a week for the past six months and cannot be using certain medications.

Inclusion Criteria

Regular menstrual cycle (21-35 days, inclusive)

I am not using any form of hormonal birth control.

Non-smoking

Exclusion Criteria

Excessive alcohol consumption (>21 units/wk)

I or someone in my family has had blood clots.

Ineligible to participate in physical activity based on get active questionnaire (GAQ)

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

4 weeks

3 visits (in-person) for blood draws and familiarization

Menstrual Cycle Tracking

Participants track their menstrual cycle for four cycles using self-reported menstrual onset and ovulation strips

16 weeks

Ongoing self-reporting

Treatment

Participants undergo resistance training based on menstrual cycle phase, with varying training volumes for FOL and LUT groups

16 weeks

Approximately 2 visits per week (in-person)

Follow-up

Participants are monitored for changes in muscle hypertrophy and strength post-training

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Menstrual Cycle Phase Based Training

Trial Overview The study tests if resistance training benefits vary across different phases of the menstrual cycle. Women's legs will be assigned to one of four groups: non-exercise control, exercise control, follicular phase training, or luteal phase training.

How Is the Trial Designed?

Group I: Luteal Based Training (LUT) Experimental Treatment 1 Intervention

This condition will have high volume of RET (20 weekly sets) during the luteal phase and low volume during the follicular phase of the participant's menstrual cycle.

Group II: Follicular Based Training (FOL) Experimental Treatment 1 Intervention

This condition will have high volume of RET (20 weekly sets) during the follicular phase and low volume during the luteal phase of the participant's menstrual cycle.

Group III: Exercise Control (EX) Experimental Treatment 1 Intervention

This condition will have consistent training volume (12 weekly sets) throughout the duration of the study, regardless of what phase of the menstrual cycle the participant is in.

Group IV: Non-Exercise Control (CON) Active Control 1 Intervention

This condition will serve as a non-exercise control and will not be performing resistance exercise training (RET)

Who Is Running the Clinical Trial?

McMaster University

Lead Sponsor

Trials

936

Recruited

2,630,000+

Published Research Related to This Trial

Research indicates that female athletes may experience optimal muscle strength and anaerobic capacity during the follicular phase of the menstrual cycle, when estrogen levels are highest.

Resistance training conducted in the follicular phase may lead to greater improvements in muscle strength and mass compared to training in the luteal phase, suggesting that menstrual cycle timing can be crucial for optimizing training outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of Follicular and Luteal Phase-Based Menstrual Cycle Resistance Training on Muscle Strength and Mass. Kissow, J., Jacobsen, KJ., Gunnarsson, TP., et al.[2022]

In a study of 14 eumenorrheic women over 12 weeks, both training frequencies during different menstrual phases (1 day/week vs. 3 days/week) led to significant increases in muscle hypertrophy and strength, indicating effective training regardless of menstrual cycle phase.

The results suggest that hormonal fluctuations during the menstrual cycle do not significantly impact muscle growth and strength gains from resistance training, as similar improvements were observed in both the follicular and luteal phases.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of Menstrual Phase-Dependent Resistance Training Frequency on Muscular Hypertrophy and Strength. Sakamaki-Sunaga, M., Min, S., Kamemoto, K., et al.[2018]

The menstrual cycle phases did not significantly affect overall training load (measured by TRIMP) in young female athletes, but training monotony and strain were higher during the follicular phase compared to the ovulatory phase.

Technical training sessions were longer during the follicular and luteal phases than during the ovulatory phase, and menstrual cycle symptoms were more pronounced in the follicular phase, suggesting that monitoring these phases could help optimize training and performance outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Menstrual cycle alters training strain, monotony, and technical training length in young. Cristina-Souza, G., Santos-Mariano, AC., Souza-Rodrigues, CC., et al.[2019]

High frequency leg resistance training during the first two weeks of the menstrual cycle led to significant improvements in strength and lean body mass in trained women, as shown in a study with 57 participants over four months.

In contrast, training during the last two weeks of the cycle did not yield the same benefits, indicating that timing within the menstrual cycle can influence the effectiveness of resistance training.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects on power, strength and lean body mass of menstrual/oral contraceptive cycle based resistance training. Wikström-Frisén, L., Boraxbekk, CJ., Henriksson-Larsén, K.[2018]

Recent research highlights the significant relationship between exercise and menstrual function, particularly focusing on exercise-related amenorrhea.

The paper reviews how fluctuations in hormones like estradiol and progesterone during the menstrual cycle can influence the body's hormonal and physiological responses to exercise.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Hormonal and physiological responses to exercise in relation to the menstrual cycle. Jurkowski, JE.[2013]

Follicular phase-based strength training (FT) resulted in greater increases in maximum isometric force and muscle diameter compared to luteal phase-based training (LT) in a study of 20 eumenorrheic women.

The study suggests that women should consider their menstrual cycle phases when planning strength training, as hormonal variations can significantly impact training outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of follicular versus luteal phase-based strength training in young women. Sung, E., Han, A., Hinrichs, T., et al.[2022]

In a study involving 13 previously untrained individuals (8 women and 5 men), muscle hypertrophy was significantly greater during the luteal phase (5.7%) compared to the follicular phase (3.7%) after 6 days of low-intensity resistance training with blood flow restriction.

Isometric strength increased significantly in the luteal phase but not in the follicular phase, indicating that the timing of training within the menstrual cycle can influence muscle growth and strength gains, while showing no significant differences between men and women in training response.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Comparison of low-intensity blood flow-restricted training-induced muscular hypertrophy in eumenorrheic women in the follicular phase and luteal phase and age-matched men. Sakamaki, M., Yasuda, T., Abe, T.[2013]

In a study involving 36 female participants over 12 weeks of resistance training, all groups (underweight, normal weight, and overweight) showed significant increases in maximum isometric force during both the follicular and luteal phases of their menstrual cycle.

However, only the underweight group exhibited a notable difference in muscle strength gains between the follicular phase and luteal phase, suggesting that BMI may influence strength outcomes depending on the phase of the menstrual cycle.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The resistance training effects of different weight level during menstrual cycle in female. Sung, ES., Kim, JH.[2020]

Citations

1. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/35471634/

Effects of Follicular and Luteal Phase-Based Menstrual ... Studies demonstrate that anaerobic capacity and muscle strength are greatest during the follicular phase of the menstrual cycle, when estrogen levels peak.

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10076834/

Current evidence shows no influence of women's ... Results indicate that exercise performance may be trivially reduced during the early follicular phase of the menstrual cycle compared to all other phases. Due ...

3. medrxiv.org medrxiv.org/content/10.1101/2024.10.28.24316287v1.full-text

Menstrual Cycle Phase-Based Interval Training Yields ... Our findings show that synching high-frequency SIT with menstrual cycle phases induces distinct muscle adaptations and affects phenotype in eumenorrheic female ...

4. trialsjournal.biomedcentral.com trialsjournal.biomedcentral.com/articles/10.1186/s13063-024-07921-4

Impact of Menstrual cycle-based Periodized training on ... - Trials Our primary hypothesis is that follicular phase-based training is superior to both luteal phase-based training and regular training throughout ...

5. frontiersin.org frontiersin.org/journals/sports-and-active-living/articles/10.3389/fspor.2025.1519825/full

Power in the flow: how menstrual experiences shape ... Research has also suggested that strength training during the late follicular phase results in greater increases in muscle strength (14, 17).

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10823667/

Impact of Menstrual cycle-based Periodized training on ... This randomized, controlled trial will provide evidence of any differential effects of exercise periodization during different phases of the menstrual cycle in ...

7. hsph.harvard.edu hsph.harvard.edu/research/apple-womens-health-study/study-updates/exploring-exercise-habits-by-menstrual-cycle-phase/

Exploring Exercise Habits by Menstrual Cycle Phase During the follicular phase participants typically exercised 21 minutes a day, compared to 20.9 minutes during the luteal phase (Figure 1). This makes sense, ...

8. mdpi.com mdpi.com/2075-4663/12/1/31

The Influence of Menstrual Cycle Phases on Maximal ... Overall, it can be concluded that the early follicular phase is unfavorable for all three tested maximal strength classes during the menstrual cycle. The late ...

9. sciencedirect.com sciencedirect.com/science/article/pii/S0765159722000569

Menstrual cycle-based undulating periodized program ... An 8-week undulating program based on the different phases of the menstrual cycle increases strength and FFM in trained eumenorrheic women.