Circadian Rhythm and Cardiovascular Recovery After Submaximal Exercise

The study will include healthy volunteers aged 18-45 years. After written informed consent is obtained, participants will complete a sociodemographic information form, the Morningness-Eveningness Questionnaire, and the Pittsburgh Sleep Quality Index. Resting heart rate, oxygen saturation, and Borg dyspnea/fatigue scores will then be recorded, followed by the 6-Minute Walk Test. Physiological measurements will be repeated immediately after the test and at the 1st, 3rd, and 5th minutes of recovery.

The planned sample size is at least 124 participants. This was calculated using G*Power 3.1.9.7 based on a medium effect size (r=0.30), a significance level of 5% (α=0.05), and 90% statistical power, with an additional 10% allowance for possible data loss or missing data. Data will be analyzed using descriptive statistics, normality analyses, appropriate parametric or non-parametric comparison tests, correlation analyses, and multivariable regression analyses, with statistical significance set at p<0.05.

Inclusion criteria

• Aged 18-45 years.
• Being healthy.
• Voluntarily agreeing to participate in the study.

Exclusion criteria

• Presence of cardiovascular, pulmonary, neurological, or orthopedic disease.
• Having a health problem that prevents exercise.
• Use of medication that may affect exercise tolerance.
• Pregnancy.