VO₂ max—is critical to aging well.

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or beginners, aim to elevate your heart rate to 50% of your max (calculated as 220 minus your age), and work up to 60–70% over time. At that level, you’ll be breathing heavily and unable to talk easily while exercising. Aim for 20 to 40 minutes of aerobic activity, 3 to 5 days a week.