Which vigorous intensity activity would likely cause older adults to be out of breath?

Cross-country skiing is a vigorous intensity activity that engages multiple muscle groups and places significant demands on the cardiovascular and respiratory systems. This high-energy exercise typically involves continuous movement across various terrains and requires both endurance and strength, making it particularly challenging. For older adults, who may have lower cardiovascular fitness or joint issues, this activity can lead to increased heart rates and prompt feelings of breathlessness, especially if they are not accustomed to such intense exertion.

In contrast, other activities listed, such as walking, light jogging, and stretching, are generally considered to have lower intensity levels. Walking, while beneficial for overall health, and light jogging may not elevate the heart rate sufficiently to cause significant breathlessness in older adults, particularly if they are regular participants in these activities. Stretching is primarily focused on flexibility and does not increase cardiovascular or muscular intensity, thus unlikely to cause breathlessness at all.