Dr. Oz's Guide to Getting Healthy in Your 40s

At age 40, you may start to experience the effects of hormonal changes as perimenopause begins to set in (menopause arrives, on average, at age 51). One thing that doesn't change: your ability to fend off serious health challenges by eating well and exercising.

Do This: Stretch

Feeling a little stiff? Poor flexibility in people over 40 has been associated with arterial rigidity, which means your heart has to work extra hard to pump blood—potentially leading to a heart attack or stroke. Here's the good news: Researchers think that stretching your muscles may also make your arteries more flexible. Use this easy, gym-class-inspired sit-and-reach test to figure out how limber you are, then try Dr. Oz's exercises to help loosen up.

1. Sit on the ground, legs extended, hip-width apart, with a yardstick positioned lengthwise between them so your heels are aligned with the 15-inch mark.
2. Slowly lean as far forward as possible with your arms outstretched, sliding your fingertips along the yardstick with the goal of reaching past your feet.
3. Return to starting position and relax for a few seconds. Repeat exercise to obtain the most accurate measurement. For women, a mark of 15 inches or less indicates poor flexibility.