AlterG Anti-Gravity Treadmill

The anti-gravity of the AlterG treadmill provides a boost for athletes and rehabilitation patients to shorten recovery time, reduce injury risk and enhance athletic performance. Froedtert & the Medical College of Wisconsin Sports Medicine is among only a few Milwaukee-area locations to offer this NASA-inspired technology, used by Olympic and pro sports teams and top university-affiliated rehabilitation/sports centers. 

AlterG for Athletic Training and Physical Therapy

AlterG anti-gravity treadmill

During any weight-bearing exercise, the hips, legs, knees, ankles and feet feel the stress. The AlterG anti-gravity treadmill uses a lifting effect to ease the impact on lower extremities. The AlterG is ideal for physical therapy after sports injuries, knee and hip replacement or stroke. It is also used to incorporate weight-bearing exercise into fitness and weight loss routines. 

Recovering patients — The AlterG assists patients who have been prescribed by their physician to start weight-bearing exercise as tolerated, such as those recovering from ACL surgery, stress fractures, joint replacement or stroke. In many cases rehabilitation with the AlterG can start sooner than with hydrotherapy. And due to it's unique design, tethers and harnesses are not needed.

Overweight and irregular exercisers — Users may find the AlterG treadmill is a gentle way to add aerobic activity to their lives, key to strengthening, building intensity and losing weight. 

Endurance athletes — Power walkers, distance runners and frequent exercisers with occasional lower-limb soreness may find the AlterG is much easier on the body during and after exercise. For athletes who cross-train in water, the AlterG offers as much resistance as, and more convenience than, a hydro workout. 

Injured athletes — Many athletes in physical therapy find they bounce back more quickly with the AlterG treadmill. Many physical therapists and sports trainers find the AlterG reduces their clients’ post-surgery recovery by days or even weeks.

Anti-Gravity Effect Reduces Impact

To use the AlterG, the patient or athlete wears specially designed shorts and is zipped into an air chamber on the treadmill. Once activated, the chamber surrounds the lower extremities in a cocoon of air, supporting the patient's body and reducing the amount of weight felt. Users can walk, run and practice other weight-bearing movement in this reduced-gravity environment. 

The degree of lift is based on an anti-gravity factor recommended by Sports Medicine Center staff. Users can feel 20 percent to 100 percent of their body weight and many training programs rely on gradually increasing the amount of weight felt. For example, a 150-pound person at a 20 percent anti-gravity factor would effectively weigh only 30 pounds in the chamber. At 50 percent, the person "weighs" 75 pounds.

The treadmill keeps a pace of up to 18 miles per hour, has adjustable incline and allows training staff to view a patient's movement from many angles.

Try It Out

Test the AlterG anti-gravity treadmill at our Froedtert Hospital campus location at 8700 W. Watertown Plank Road. Reserve a 30-minute session for $15 by calling 414-805-7100. Appointments are required and subject to availability.


For sports medicine:

  • 414-805-3666
Request AppointmentView Treatment Team


Sports Medicine Center 8700 W. Watertown Plank Road Milwaukee, WI 53226

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