Acute Exercise, Endocrine Response, Sedentary Behavior
Conditions
Keywords
Aerobic Exercise, Anaerobic Exercise, Sedentary Women, Cortisol, Thyroid Hormones
Brief summary
This study aims to compare acute thyroid hormone and cortisol responses to aerobic and anaerobic exercise in sedentary women. Thirty sedentary women aged 18-25 years will voluntarily participate in the study. Participants will complete a 20-meter shuttle run test as the aerobic exercise protocol and a 30-second Wingate test as the anaerobic exercise protocol in separate testing sessions. Blood samples will be collected immediately before and after each exercise protocol. Serum thyroid-stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), and cortisol concentrations will be determined using chemiluminescence-based laboratory methods. Changes in hormone concentrations will be compared between the aerobic and anaerobic exercise conditions.
Detailed description
This interventional study is designed to compare the acute endocrine responses elicited by aerobic and anaerobic exercise in sedentary women. A total of 30 healthy sedentary women aged 18-25 years will voluntarily participate. Individuals who have engaged in regular exercise or sports training, experienced a serious upper- or lower-extremity injury during the previous six months, or had a neurological, auditory, visual, or vestibular disorder during the previous year will not be included. Before participation, all individuals will be informed about the study procedures, provide written informed consent, and undergo medical screening. Each participant will complete aerobic and anaerobic exercise protocols in separate testing sessions. The aerobic exercise protocol will consist of a progressive 20-meter shuttle run test. Participants will run continuously between two lines positioned 20 meters apart, following prerecorded audio signals. Running speed will progressively increase as the interval between signals decreases. The test will end when a participant fails to reach the designated line before the signal on two consecutive occasions. The anaerobic exercise protocol will consist of a 30-second Wingate test performed on a Monark cycle ergometer connected to computerized analysis software. Following an unloaded acceleration period of approximately 3-4 seconds, an external resistance equivalent to 65 g/kg of body mass will be applied. Participants will be instructed to pedal against this resistance at maximal effort for 30 seconds. Four venous blood samples will be collected from each participant: immediately before and after the aerobic exercise protocol and immediately before and after the anaerobic exercise protocol. Each sample will consist of approximately 8 mL of blood collected from an antecubital vein by qualified healthcare professionals under medical supervision. The samples will be centrifuged at 3,500 revolutions per minute to separate serum and plasma. Serum thyroid-stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), and cortisol concentrations will be measured using chemiluminescence-based laboratory methods. Exercise testing will be conducted at the Hasan Doğan School of Physical Education and Sports Laboratory at Karabuk University. Laboratory analyses will be performed at the Public Health Laboratory of the Karabuk Provincial Health Directorate. Pre-to-post-exercise changes in hormone concentrations will be evaluated within each exercise condition and compared between the aerobic and anaerobic exercise protocols.
Interventions
Participants will perform a progressive 20-meter shuttle run test by running continuously between two lines positioned 20 meters apart in time with prerecorded audio signals. The initial running speed will progressively increase as the interval between audio signals decreases. The test will end when the participant fails to reach the designated line before the signal on two consecutive occasions.
Participants will perform a 30-second Wingate anaerobic test on a Monark cycle ergometer connected to computerized analysis software. Following an unloaded acceleration phase of approximately 3-4 seconds, a resistance corresponding to 65 g/kg of body mass will be applied. Participants will be instructed to pedal against this resistance at maximal effort for 30 seconds. Peak power, mean power, minimum power, and fatigue index will be recorded.
Sponsors
Study design
Intervention model description
Each participant will complete both the aerobic and anaerobic exercise interventions in two separate testing sessions and will serve as her own control. Acute changes in thyroid hormone and cortisol concentrations from before to after each exercise protocol will be compared between the two exercise conditions.
Eligibility
Inclusion criteria
* Female participants aged 18-25 years * Studying at the Faculty of Sports Sciences of Yalova University * Not actively participating in regular exercise or sports training * Voluntarily agreeing to participate in the study * Providing written informed consent * Being medically eligible to perform the exercise protocols following preparticipation medical screening
Exclusion criteria
* Having a neurological disorder during the previous year * Having an auditory, visual, or vestibular disorder during the previous year * Having experienced a serious upper- or lower-extremity injury during the previous six months * Having any medical condition identified during screening that could prevent safe participation in maximal exercise testing * Being unable or unwilling to complete either exercise protocol or blood-sampling procedures
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Change in Serum Cortisol Concentration | Immediately before and immediately after each exercise protocol |
Countries
Turkey (Türkiye)