“You need at least an hour of exercise every day to be healthy.”
Adult activity guidelines recommend weekly amounts well below an hour each day and recognize benefits from smaller amounts. Short bouts count, so an hour daily is not a necessary threshold.
Adults do not need an hour of exercise every day to benefit. Guidelines recommend at least 150 minutes of moderate activity weekly, or 75 minutes vigorous, plus strengthening on two days. Smaller amounts still help.
A short walk can be a useful starting point. It is not a guarantee that you have left a particular risk category.
Start with an amount you can manage and work toward a weekly routine. Short bouts can count toward the total.
Similar claims on Minimum effective dose of exercise
This is the health movement in one finding: you don't need an hour a day or a perfect routine. A brisk 15-minute walk, or two weekend sessions, already moves you out of the highest-risk group. Small steps, real progress.