The types of exercise you do after an ankle injury will depend on the kind of injury you sustained, how serious it is and whether your doctor clears you. For a mild ankle injury that is a few weeks old, the elliptical machine might be a great low-impact way to do your cardio. If you broke an ankle last week or suffered a severe sprain a few days ago, you should work with your doctor and physical therapist to design a safe exercise program for your situation.
Ankle pain is a symptom of a variety of problems. FamilyDoctor.org explains that ankle pain that starts after a fall or a twisting injury might indicate a fracture or sprain. If you can't bear weight on the ankle, see a doctor right away. If you can bear weight on the foot but you still have a lot of swelling, keep the foot elevated and let it rest. If it still hurts after a day or so, call your doctor.
For the first 48 to 72 hours after an acute ankle injury, the most important thing you can do for your foot is to use the "PRICE" treatment: protect the foot, rest it, ice it, compress it by gently wrapping with a bandage and elevate it. If your doctor clears you after the first 72 hours, you can start gentle exercise again. Depending on the severity of your injury, you may be limited to drawing circles in the air with your foot or exerting force against an immovable object, like a wall.
If you have a severe ankle injury, your doctor might recommend you get your aerobic exercise in a nonweight-bearing form, like walking or running in the water or using a stationary bike. The elliptical machine, though low-impact, still requires your ankle to support your full body weight. It also involves a large range of motion in the ankle. In the first weeks after a serious injury, that may make the situation worse. If you fractured the joint, excess strain can cause the bones to move out of place.
After your ankle stabilizes or if your injury was mild, the elliptical might be a good addition to your workout. Unlike walking outdoors, you can stop whenever you need to. The ground impact forces on the elliptical are less than in running, and since all the motion is controlled and there is no twisting or turning, you are not likely to roll off your ankle like you might in a step class.
As you recover from your injury, pain should always be your guide. Stop whenever your ankle starts to hurt. Depending on how severe the injury was, it could take months before you are able to move like you did before the injury. Exercise is critical to helping the injury heal properly and preventing reinjury. Your doctor and physical therapist can help you make sure you choose the right exercise plan for your injury.