Walking at what speed (in miles per hour) is considered a moderate-level activity?

Walking at a speed of 4 miles per hour is considered a moderate-level activity because it tends to elevate the heart rate without causing excessive fatigue, enabling individuals to maintain a conversation while still exercising. This speed strikes a balance between being brisk enough to provide cardiovascular benefits while remaining manageable for most people.

Moderate-intensity activities, as defined by organizations such as the Centers for Disease Control and Prevention (CDC) and the American Heart Association (AHA), typically fall within a range where an individual's breathing and heart rate increase but they can still talk comfortably. Four miles per hour aligns well with this criterion, making it a common benchmark for assessing moderate-intensity walking.

In contrast, speeds lower than 4 miles per hour, like 2 or 3 miles per hour, may not elicit sufficient increases in heart rate and effort to be classified as moderate activity. Conversely, speeds above 4 miles per hour, such as 5 miles per hour, generally enter the category of vigorous activity, where participants may have difficulty conversing due to increased exertion.