The Impact of the Menstrual Cycle on Physical Exercise and Performance

Overview

The menstrual cycle implies a basic difference in the biology of women and men but the effect of the hormonal variation on training protocols and physical performance is still not fully understood. Despite no existing evidence, the advice to periodize exercise according to the menstrual cycle has been widely spread among elite athletes, coaches, and sports federations. The advice is based on underpowered studies with considerable methodological weaknesses regarding determination of cycle phase, inclusion of athletes and lack of adequate control groups. The purpose of this randomized, controlled study is to evaluate the effect of exercise periodization on aerobic fitness during different phases of the menstrual cycle. Further, the effect will be related to premenstrual symptoms, body composition and skeletal muscle morphology, sex hormone receptors, metabolic enzymes, and markers of muscle protein synthesis. This study will be well controlled and follow methodology recommendations for menstrual cycle research in sports and exercise. Female athletes of fertile age will be randomized to different training regimens during three menstrual cycles (12 weeks): Group A: Training three times a week throughout the menstrual cycle. Group B: Follicular phase-based training five times a week during the follicular phase and thereafter once a week during the luteal phase. Group C: Luteal phase-based training five times a week during the luteal phase and once a week in the follicular phase. The exercise will consist of high intensity intermittent spinning classes. Assessment of aerobic fitness and power will be performed at baseline, and again after three completed menstrual cycles. On the same day, body composition will be examined by DXA and blood samples will be collected for analysis of hormones and binding proteins. To confirm menstrual cycle phase, blood samples will be collected for hormone determination, and urinary stick will be used for detection of ovulation. Subjective ratings of menstrual cycle related symptoms will be performed every day. In a subgroup of women, muscle biopsies will be collected from m vastus lateralis at baseline and at the end of the study. This study will contribute to improved knowledge about exercise periodization in relation to the menstrual cycle. Well-grounded data is crucial to give evidence-based recommendations to female athletes when planning their training protocol to optimize training results and performance.

Interventions

• Other Periodization of training
  Participants in the three arms will exercise the same dose and number of sessions distributed in three different ways.

Primary outcome measures

• Change in aerobic performance [Time frame: Change from baseline aerobic performance at the end of Cycle 4 (each cycle is around 28 days)]

Secondary outcome measures (11)

• Change in muscle strength [Time frame: Change from baseline muscle strength at the end of Cycle 4 (each cycle is around 28 days)]
• Change in one-leg sit-to-stand test [Time frame: Change from baseline test at the end of Cycle 4 (each cycle is around 28 days)]
• Change in one-leg hop test for distance [Time frame: Change from baseline test at the end of Cycle 4 (each cycle is around 28 days)]
• Change in body composition [Time frame: Change from baseline body composition at the end of Cycle 4 (each cycle is around 28 days)]
• Change in body composition [Time frame: Change from baseline body composition at the end of Cycle 4 (each cycle is around 28 days)]
• Premenstrual symptoms [Time frame: Every day during the study period]
• Change in metabolic serum markers [Time frame: Change from baseline metabolic serum markers at the end of Cycle 4 (each cycle is around 28 days)]
• Change in mucle morphology [Time frame: Change from baseline muscle morphology at the end of Cycle 4 (each cycle is around 28 days)]
• Change in muscle tissue steroid hormones [Time frame: Change from baseline muscle tissue steroid hormones at the end of Cycle 4 (each cycle is around 28 days)]
• Change in muscle protein synthesis [Time frame: Change from baseline muscle protein synthesis at the end of Cycle 4 (each cycle is around 28 days)]
• Dysmenorrhea [Time frame: Through study completion, an average of 4 month]

Eligibility criteria

Inclusion criteria

• Women exercising at least 3-4 times a week on a high level
• Regular menstrual cycle with 26-32 cycle days.
• Fully healthy and be able to follow the training program.

Exclusion criteria

• Hormonal contraceptive users,
• Users of regular medication
• Chronic disease
• Past or present neurological disorder
• Recent musculoskeletal injury

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Basic science

Study locations

Sweden · 1 center

• Angelica Lindén Hirschberg — Stockholm

Publications

• von Rosen P, Ekenros L, Solli GS, Sandbakk O, Holmberg HC, Hirschberg AL, Friden C. Offered Support and Knowledge about the Menstrual Cycle in the Athletic Community: A Cross-Sectional Study of 1086 Female Athletes. Int J Environ Res Public Health. 2022 Sep 21;19(19):11932. doi: 10.3390/ijerph191911932. PMID 36231231
• Ekenros L, von Rosen P, Solli GS, Sandbakk O, Holmberg HC, Hirschberg AL, Friden C. Perceived impact of the menstrual cycle and hormonal contraceptives on physical exercise and performance in 1,086 athletes from 57 sports. Front Physiol. 2022 Aug 30;13:954760. doi: 10.3389/fphys.2022.954760. eCollection 2022. PMID 36111164
• Ekenros L, Backstrom T, Hirschberg AL, Friden C. Changes in premenstrual symptoms in women starting or discontinuing use of oral contraceptives. Gynecol Endocrinol. 2019 May;35(5):422-426. doi: 10.1080/09513590.2018.1534097. Epub 2019 Jan 22. PMID 30668208
• Von Rosen P, Kottorp A, Friden C, Frohm A, Heijne A. Young, talented and injured: Injury perceptions, experiences and consequences in adolescent elite athletes. Eur J Sport Sci. 2018 Jun;18(5):731-740. doi: 10.1080/17461391.2018.1440009. Epub 2018 Mar 3. PMID 29504456
• von Rosen P, Heijne A, Frohm A, Friden C. Menstrual irregularity and use of oral contraceptives in female adolescent athletes in Swedish National Sports High Schools. Int J Adolesc Med Health. 2017 Nov 23;32(2):/j/ijamh.2020.32.issue-2/ijamh-2017-0113/ijamh-2017-0113.xml. doi: 10.1515/ijamh-2017-0113. PMID 29168967
• Ekenros L, Papoutsi Z, Friden C, Dahlman Wright K, Linden Hirschberg A. Expression of sex steroid hormone receptors in human skeletal muscle during the menstrual cycle. Acta Physiol (Oxf). 2017 Feb;219(2):486-493. doi: 10.1111/apha.12757. Epub 2016 Aug 9. PMID 27438889
• Ekenros L, Hirschberg AL, Heijne A, Friden C. Oral contraceptives do not affect muscle strength and hop performance in active women. Clin J Sport Med. 2013 May;23(3):202-7. doi: 10.1097/JSM.0b013e3182625a51. PMID 22948447
• Ekenros L, Hirschberg AL, Backstrom T, Friden C. Postural control in women with premenstrual symptoms during oral contraceptive treatment. Acta Obstet Gynecol Scand. 2011 Jan;90(1):97-102. doi: 10.1111/j.1600-0412.2010.01021.x. Epub 2010 Nov 26. PMID 21275922

Identifiers

NCT: NCT05697263 · 2021-01650

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗