This study looks at how *exercise* affects the blood vessels of women who are in different stages of menopause, which is the time when women's menstrual periods stop. Researchers are inviting postmenopausal women, meaning those who have stopped having periods, to join. Participants will be divided into four groups. Two groups will exercise, and two won't. All women will take a test to see how much oxygen they can use when exercising. This test is done on a special bike called a *cycle ergometer*. The exercise groups will exercise at a set level for three months, while the other groups will not. The scientists will check how well the blood vessels work before and after the study.

• The study lasts for three months with exercise training for some participants.
• Participants must be postmenopausal and free from heart diseases.
• Ineligible if you have certain health conditions like diabetes or high blood pressure.