Biomechanical Changes During Menstrual Cycle

Study Overview
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Brief Summary
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The aim of the work is to assess the effect of the menstrual cycle on the biomechanical properties of the muscles. The study will be conducted among young women aged 20-25 with a regular menstrual cycle. During the test, muscle strength and muscle flexibility as well as activation times will be performed. The study will assess the effect of the stretching of the hamstring muscles on the biomechanical properties of the muscles in the different phases of the menstrual cycle.

Official Title
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Biomechanical Changes in Young Women During Menstrual Cycle

Conditions
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Menstrual Cycle, Passive Stretching, Hamstring Muscles

Intervention / Treatment
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* Procedure: Static stretching


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Regular menstrual cycle lasting 28 days (+/- 5 days) A menstrual cycle that has been present for at least 2 years No hormonal contraception Lack of pain in the lower spine No restriction of mobility in the hip joint Exclusion Criteria: Irregular menstrual cycle BMI value below 18.5 and above 25 Orthopedic disorders in the lower limb Neurological disorders Normal flexibility of the hamstring muscles

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 26 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Young women during various of phases of menstrual cycle.<br>The group of 40 young women will have their hamstring muscle stretched in different phases of the menstrual cycle: follicular, ovulatory and luteal. Static stretching will last 3x 45 seconds with a 15 second break between repetitions. Before and after the intervention a series of tests will be performed. | Procedure: Static stretching<br>* Static stretching lasting 3 x 45 seconds will be performed in each of the examined women three times in different phases of the menstrual cycle: follicular, ovulatory and luteal. Before and after the intervention, a series of tests assessing the influence of stretching on biomechanical parameters will be carried out<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hamstring flexibility | Hamstring flexibility will be assessed using AKE and PKE and SLR tests. | Change measured before and immediately after static stretching during follicular phase of menstrual cycle | 
| Hamstring flexibility | Hamstring flexibility will be assessed using AKE and PKE and SLR tests. | Change measured before and immediately after static stretching during ovulation phase of menstrual cycle | 
| Hamstring flexibility | Hamstring flexibility will be assessed using AKE and PKE and SLR tests. | Change measured before and immediately after static stretching during luteal phase of menstrual cycle | 
| Passive Hamstring flexibility | Hamstring flexibility will be assessed using PKE test | Change measured before and immediately after static stretching during follicular phase of menstrual cycle | 
| Passive Hamstring flexibility | Hamstring flexibility will be assessed using PKE test | Change measured before and immediately after static stretching during ovulation phase of menstrual cycle | 
| Passive Hamstring flexibility | Hamstring flexibility will be assessed using PKE test | Change measured before and immediately after static stretching during luteal phase of menstrual cycle | 
| Active Hamstring flexibility | Hamstring flexibility will be assessed using SLR tests. | Change measured before and immediately after static stretching during follicular phase of menstrual cycle | 
| Active Hamstring flexibility | Hamstring flexibility will be assessed using SLR tests. | Change measured before and immediately after static stretching during ovulation phase of menstrual cycle | 
| Active Hamstring flexibility | Hamstring flexibility will be assessed using SLR tests. | Change measured before and immediately after static stretching during luteal phase of menstrual cycle | 
| Hamstring passive stifness | Hamstring stiffness will be assessed using TDK test. During the test the resistance of the elongated Hamstring muscle is measured. If the resistance value is smaller after the intervention it means that muscle stiffness changed. | Change measured before and immediately after static stretching during follicular phase of menstrual cycle | 
| Hamstring passive stifness | Hamstring stiffness will be assessed using TDK test. During the test the resistance of the elongated Hamstring muscle is measured. If the resistance value is smaller after the intervention it means that muscle stiffness changed. | Change measured before and immediately after static stretching during ovulation phase of menstrual cycle | 
| Hamstring passive stifness | Hamstring stiffness will be assessed using TDK test. During the test the resistance of the elongated Hamstring muscle is measured. If the resistance value is smaller after the intervention it means that muscle stiffness changed. | Change measured before and immediately after static stretching during luteal phase of menstrual cycle | 
| Trunk acivity is assessed using Stabilizer Pressure Biofeedback | The torso activation scheme is measured during lower and upper limb motions using Chattanooga Stabilizer Pressure Biofeedback. | Three repetitions with a 30-second break between. The measure is taken during follicular phase of menstrual cycle | 
| Trunk acivity is assessed using Stabilizer Pressure Biofeedback | The torso activation scheme is measured during lower and upper limb motions using Chattanooga Stabilizer Pressure Biofeedback. | Three repetitions with a 30-second break between. The measure is taken during ovulation phase of menstrual cycle | 
| Trunk acivity is assessed using Stabilizer Pressure Biofeedback | The torso activation scheme is measured during lower and upper limb motions using Chattanooga Stabilizer Pressure Biofeedback. | Three repetitions with a 30-second break between. The measure is taken during luteal phase of menstrual cycle | 
| Hamstring strength is tested using the Micro Fet Handheld Dynamometer. | Muscle strength of hamstring is tested. Three repetitions of muscle strength testing are performed with two 30-second intervals. The participants are asked to press against the Dynamometer with the maximum effort for 5-7 seconds. | Change measured before and immediately after static stretching. The measure is taken during follicular phase of menstrual cycle | 
| Hamstring strength is tested using the Micro Fet Handheld Dynamometer. | Muscle strength of hamstring is tested. Three repetitions of muscle strength testing are performed with two 30-second intervals. The participants are asked to press against the Dynamometer with the maximum effort for 5-7 seconds. | Change measured before and immediately after static stretching. The measure is taken during ovulation phase of menstrual cycle | 
| Hamstring strength is tested using the Micro Fet Handheld Dynamometer. | Muscle strength of hamstring is tested. Three repetitions of muscle strength testing are performed with two 30-second intervals. The participants are asked to press against the Dynamometer with the maximum effort for 5-7 seconds. | Change measured before and immediately after static stretching. The measure is taken during luteal phase of menstrual cycle | 
| Strength of arm flexors and extensors and hip flexors is tested using the Micro Fet Handheld Dynamometer. | Muscle strength of arm flexors and extensors and hip flexors is tested. Three repetitions of muscle strength testing are performed with two 30-second intervals. The participants are asked to press against the Dynamometer with the maximum effort for 5-7 seconds. | Three repetitions for 5-7 seconds with two 30-second intervals . The measure is taken during follicular phase of menstrual cycle | 
| Strength of arm flexors and extensors and hip flexors is tested using the Micro Fet Handheld Dynamometer. | Muscle strength of arm flexors and extensors and hip flexors is tested. Three repetitions of muscle strength testing are performed with two 30-second intervals. The participants are asked to press against the Dynamometer with the maximum effort for 5-7 seconds. | Three repetitions for 5-7 seconds with two 30-second intervals . The measure is taken during ovulation phase of menstrual cycle | 
| Strength of arm flexors and extensors and hip flexors is tested using the Micro Fet Handheld Dynamometer. | Muscle strength of arm flexors and extensors and hip flexors is tested. Three repetitions of muscle strength testing are performed with two 30-second intervals. The participants are asked to press against the Dynamometer with the maximum effort for 5-7 seconds. | Three repetitions for 5-7 seconds with two 30-second intervals . The measure is taken during luteal phase of menstrual cycle |