I would tell Andrea to practice a lot and perform aerobic exercises. These type of exercise, also known as "cardio", requires pumping of oxygenated blood by the heart to deliver oxygen to working muscles. In other words, by doing continuous, rythmic movements of large muscles your lungs and heart will get stronger. As a consequence, she will be able to keep physical activity for a longer time. Some exmaples of aerobic activities are: jump rope, running, swimming, stationary bike.
To develop an effective routine she will probably need to go to a personal trainer.