Physical activity is a core component of a healthy lifestyle and covers a range of activities from incidental movement such as commuting to leisure-time physical activity such as sports and exercises that encompasses different intensities (low, moderate, or vigorous).
Moderate-intensity physical activities refer to those that cause a noticeable increase in breathing rate and heart rate. For instance, individuals who brisk walk should get to an intensity where they would be able to talk in phrases or short sentences but do not have enough breath to sing.
Vigorous-intensity physical activities refer to those that cause large increases in breathing rate and heart rate. For instance, one would typically have difficulty talking while jogging.
MVPA refers to Moderate to Vigorous Physical Activity. For more information on physical activities of different intensities, please refer to here.