Effects of the Menstrual Cycle on Triceps Surae Properties in Women
Trial statusRecruiting
Trial phaseNot listed
Trial typeObservational
Biological sexFemale
Age18-30
SponsorMarco Aurélio Vaz, PhD
About this trial
The menstrual cycle is an important biological rhythm, whereby large cyclic fluctuations in endogenous sex hormones, such as estrogen and progesterone, are observed, which can affect performance. Evidence shows that endogenous and exogenous changes in hormone concentrations during the menstrual cycle exert many effects on the nervous and endocrine systems, in addition to the connective tissue, with consequences for the movement system. Pre-clinical studies (i.e., in animal models) show an estrogen association with the structural and mechanical properties of tendons and ligaments. Several elegant studies performed with female participants have tried to establish the mechanism underlying the effect of estrogen on collagen synthesis and its effects on exercise and functionality. Their findings suggest that the tendon properties may be affected when exposed to varying concentrations of estrogen. The largest tendon in humans, the Achilles tendon, has a direct role in functional capacity, activities of daily living, and locomotion. Studies show that the triceps surae's structural and mechanical properties may change throughout the menstrual cycle, and that these changes are related to endogenous and exogenous fluctuations in estrogen and progesterone. Musculotendinous stiffness, which is dependent on the collagen content, has been seen to vary considerably over the course of the menstrual cycle. In addition, it has been reported that females who have been taking the contraceptive pill for at least a year demonstrate lower levels of tendon strain compared to non-pill taking females, indicating a possible influence of hormonal state on tendon mechanical properties. However, the different experimental designs, the varied approaches to the evaluations and the lack of studies with high methodological quality limit our understanding of the effects of the different phases of the menstrual cycle on the triceps surae's neuromechanical properties. The aim of this observational study will be to investigate whether the morphological, mechanical (active and passive), material, and functional properties of the plantar flexor muscles and of the Achilles tendon, as well as functional parameters, change during voluntary contractions throughout the phases of the menstrual cycle in eumenorrheic women and in users of hormonal contraception. Understanding the acute effects of these properties in eumenorrheic women and users of hormonal contraception is essential so that we can adequately plan interventions and prescriptions of physical exercise and rehabilitation aimed for women.
Eligibility criteria
This trial does not accept healthy volunteersQualifiers
Inclusion criteria for the group of eumenorrheic women
Being eumenorrheic with a regular menstrual cycle lasting between 21 and 35 days during the last 6 months prior to study participation.
Body Mass Index between 20 and 25 kg/m2.
Normal ankle function and range of motion.
Disqualifiers
Women who have anovulatory cycles or phase lutea deficiency.
Women in early menopause.
Pregnant or lactating women.
Women with oligomenorrhea (menstrual cycles longer than 35 days, or delay of menstruation for the same period).
Trial population
Over the last three decades, there has been a rise in the number of women participating in exercise, from physical activity to elite sports. However, the number of studies regarding female participants' performance is still small compared to male participants. The menstrual cycle is an important biological rhythm, whereby large cyclic fluctuations in endogenous sex hormones, such as estrogen and progesterone, are observed, which can affect performance.
Trial design
Design model
Other
Time perspective
Cross-sectional
Treatments tested in this trial
Evaluations of the mechanical properties of the achilles tendon in different phases of the menstrual cycle
Other interventionMonitoring assessments to verify the effect of different phases of the menstrual cycle on the neuromechanical properties of the Achilles tendon.
Treatment groups
40 Participants
are divided into 4 treatment groupsGroup A: Physically active eumenorrheic women with regular menstrual cycle1 intervention
Group B: Sedentary eumenorrheic women with regular menstrual cycle1 intervention
Group C: Physically active women using hormonal contraceptives1 intervention
Group D: Sedentary women who use hormonal contraception1 intervention
Trial outcomes
Primary outcomes
1
Maximal voluntary isometric contraction (Nm)
Maximal voluntary isometric contraction (MVIC) of the plantar flexor muscles, i.e., largest plantar flexor torque generated in different phases of menstrual cycle and different moments of contraception use
Time frame
The assessment will be performed at the beginning (1-4 days), middle (10-14 days), and end (22-26 days) of Cycle 1 (each menstrual cycle is between 28-30 days).2
Achilles tendon stiffness (N/mm)
Achilles tendon stiffness will be calculated during maximal voluntary contraction in different phases of menstrual cycle and contraception users
Time frame
The assessment will be performed at the beginning (1-4 days), middle (10-14 days), and end (22-26 days) of Cycle 1 (each menstrual cycle is between 28-30 days).Secondary outcomes
1
Cross-sectional area (mm²)
The evaluation of the cross-sectional area will be carried out using ultrasound, evaluating proximal, medial and distal portions from the calcaneus bone.
Time frame
The assessment will be performed at the beginning (1-4 days), middle (10-14 days), and end (22-26 days) of Cycle 1 (each menstrual cycle is between 28-30 days).2
tendon stress (MPa) during maximal voluntary contractions
The stress will be obtained by taking the ratio between Achilles tendon strength and tendon cross sectional area, and tension taking the relationship between tendon elongation and tendon length at rest
Time frame
The assessment will be performed at the beginning (1-4 days), middle (10-14 days), and end (22-26 days) of Cycle 1 (each menstrual cycle is between 28-30 days).3
Myotendinous junction displacement (mm)
The displacement of the myotendinous junction of the medial gastrocnemius muscle (DTJM) will be evaluated during passive torque assessment.The analysis will be carried out in three core cycles of the five passive torque cycles.
Time frame
The assessment will be performed at the beginning (1-4 days), middle (10-14 days), and end (22-26 days) of Cycle 1 (each menstrual cycle is between 28-30 days).4
Ankle functionality (cm)
Ankle functionality and ankle dorsiflexion range of motion assessed through functional heel raise theses.
Time frame
The assessment will be performed at the beginning (1-4 days), middle (10-14 days), and end (22-26 days) of Cycle 1 (each menstrual cycle is between 28-30 days).Sponsors and contacts
Click on the lead sponsor to view all of their trials.
Marco Aurélio Vaz, PhD
Lead sponsor
Federal University of Rio Grande do Sul
Sponsor institution
Source ClinicalTrials.gov