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What is an AlterG anti-gravity treadmill, and who is it for?
An AlterG anti-gravity treadmill uses air pressure inside a sealed chamber around your lower body to lift away part of your body weight, up to 80 percent of it, so you can walk or run with less load on your joints. Physical therapists use it to get people moving and training sooner after a lower-body injury or surgery, such as a meniscus or ACL tear or a knee or hip replacement. They increase the load step by step as healing allows.
Our clip of a patient on the AlterG is one of the most-watched videos on our channel. The most common question in the comments is simple: what is that machine? Here is how it works and who it helps, in the words of the clinicians who use it.
How does an anti-gravity treadmill work?
You put on a pair of snug shorts that zip into an inflatable chamber around the treadmill. Once you are sealed in, the machine raises the air pressure inside the chamber. That gently lifts you and takes a chosen share of your body weight off your legs and joints.
In the longer video below, our clinician explains it with simple math. If a person weighs 100 pounds and the treadmill takes away 20 percent of their body weight, they run as if they weighed 80 pounds. The AlterG can take away up to 80 percent of body weight, and the therapist can keep the same speed or increase it while reducing the load.
Because the support is precise and adjustable, progress is easy to measure. Over a series of sessions, the therapist gradually gives back more body weight as healing allows.
Who is the AlterG for?
In the video, our clinician describes using it for:
- Knee replacements and hip replacements, to get people walking and bearing weight sooner and with more confidence
- ACL tears and meniscus tears, before or after surgery, as part of rehab
- Ankle injuries and other lower-body injuries
- Runners and endurance athletes who want to keep training while an injury heals. One patient in the video, a marathon runner with a torn meniscus, kept training on the AlterG alongside physical therapy
- Elite athletes and weekend warriors alike, for training and "active recovery"
It also suits people who cannot yet tolerate walking at full body weight, for example because of pain or a recent operation.
It is not just for running
Therapists also use the reduced-weight setting for strengthening and balance work. In the clip below, a patient does slow incline walking to get the quadriceps working, then side steps to target the glutes. Changing the incline changes which muscles work hardest.
Benefits our therapists look for
- Walking and running with less pain and less impact on healing joints
- Starting to walk sooner and for longer, with support and less fear of falling
- Keeping up aerobic fitness while an injury or surgery heals
- Measured, gradual progress back to full body weight
The AlterG does not replace the rest of rehab. It is one tool inside a plan that also includes hands-on treatment, strengthening and balance training, and your surgeon's protocol after an operation.
Is an anti-gravity treadmill right for you?
Whether it fits depends on your injury, your surgery and how you are healing. Some conditions and incisions need clearance first, so a clinician should decide when you start and how much weight to take away. After surgery, check with your surgeon before starting.
Related care at Precision Care
Where to get care in New York City
Precision Care lists AlterG training for its Brooklyn, Staten Island and Midtown Manhattan offices. Call ahead to confirm which location offers it on the day you need. You can request an appointment online or call the office closest to you. An online request is not a confirmed booking until the office contacts you.
150 E 55th St, Suite 401, New York, NY 10022
(212) 840-0135
Questions patients ask
How much body weight can the AlterG take off?
The AlterG can reduce the load on your legs by up to 80 percent of your body weight. For example, a 100-pound person with 20 percent removed walks or runs as if they weighed 80 pounds. Your therapist chooses the setting and adjusts it as you heal.
Who uses an anti-gravity treadmill?
Physical therapists use it for people recovering from lower-body injuries and surgery, such as knee and hip replacements, ACL and meniscus tears and ankle injuries. Runners and other athletes also use it to keep training while an injury heals.
Is the AlterG only for running?
No. Therapists also use it for walking, incline walking and side steps to strengthen the quadriceps and glutes, and for balance work, all with part of your body weight removed.
Can I use the AlterG right after surgery?
That depends on the surgery, your incision and your surgeon's protocol. Your surgeon and therapist decide when it is safe to start and how much weight to take away.
Where can I use an AlterG in New York City?
Precision Care offers AlterG training as part of physical therapy in Brooklyn, Staten Island and Midtown Manhattan. Call the office to confirm which location offers it on the day you need.
Educational only, not medical advice. These videos and this article explain common treatments in general terms. They are not a diagnosis or a treatment plan for you. Results vary from person to person. See a qualified clinician about your own symptoms, and call 911 or go to an emergency room for an emergency.
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