Make a hypothesis. Predict how the amount of water erosion that occurs on a slope will be affected by variations in the slope gradient, presence of absence of vegetation, and rain intensity.

Yoga and strength training are both anaerobic, I believe.
An hour of quick walking would undoubtedly work the cardiovascular system, but an hour seems intense.
Twenty-five minutes of intense interval training would be ideal, as the intensive exercise is interspersed with less intense rest exercises. It has also been shown that this type of training is more efficient than training at a steady level for a longer period (for example, an hour of quick walking).