Moderate Aerobic Exercise for Managing Menstrual Cycle Symptoms

Inclusion Criteria: * premenopausal (defined as having regular menstrual periods every 21-35 days) * either not using hormonal or non-hormonal contraceptives (i.e., intrauterine device) for the past 6 months OR using combined oral contraceptives (i.e., those that contain progesterone and estrogen) for at least the past 6 months * not currently pregnant or trying to become pregnant * sedentary lifestyle (score of "low activity/inactive" assessed using the IPAQ) * have self reported menstrual cycle symptoms (symptoms reported on the PSST or MSi) * do not have a medical diagnosis or signs/symptoms of diabetes, cardiovascular, or renal disease and are able to participate in moderate intensity physical activity without physician clearance Exclusion Criteria: * becoming physically active defined as scoring higher than "low activity/inactive" on the IPAQ during the first month of the study * non compliance with instructions provided for the moderate aerobic exercise intervention (i.e., not adhering to predetermined intensity heart rate targets) or miss more than 25% of exercise sessions in either intervention month * becoming pregnant during enrollment * being diagnosed with a cardiovascular, metabolic, or renal disease that would require physical clearance to participate in moderate intensity aerobic physical activity * begin using hormonal or non-hormonal (i.e., intrauterine devices) contraceptives if assigned to the arm not using hormonal contraceptives * either begin a different type of contraceptive or discontinue combined hormonal contraceptive use if assigned to the hormonal contraceptive arm