“What is the best type of exercise to improve mitochondrial function? Many studies have examined this.

First, it needs to be an endurance type of exercise, such as walking, exercising on a treadmill, swimming, or cycling, as opposed to a non-endurance activity like weight lifting. Second, it is most effective if you are either fasting or do not eat any carbohydrates before the exercise. Third, the exercise has to be sustained for at least one hour, and be done at least three or four times a week. This is because it takes some time to activate the process of mitochondrial growth, and exercising less than thirty minutes at a time rarely achieves this.”

Richard Johnson and David Perlmutter, Nature Wants Us to Be Fat