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The AlterG: The Amazing Anti-Gravity Treadmill

Using the latest anti-gravity technology to assist with Physical Therapy

The journey of rebuilding the body and mending everything from a sprain to a fracture is a delicate process. Thankfully, technology has come a long way to help make the process a little easier. The healing process for injuries is slow and tedious, giving our physical therapists the need to use any tools at their disposal for a faster recovery. One of those new tools made recently available for Physical Therapy is the AlterG, which is  a state of the art Anti-Gravity Treadmill.

A Little History on the AlterG

The story of how the anti-gravity treadmill came to exist is quite fascinating. The idea and technology surprisingly came from NASA, having been developed originally as a method to create differential air pressure (DAP). DAP is a method designed to acclimate Astronauts to Zero-G training for missions. The DAP technology found its way to the world of physical therapy when AlterG purchased the patent. The technology’s current path grew to a treadmill designed to recover from injuries.

What does the AlterG do?

 The AlterG is a state of the art treadmill. The AlterG calculates your body weight and uses air displacement to make your body weight lighter than normal. This makes it easier for people who have hip or knee injuries and can’t fully handle the impact caused by regular treadmill running. The AlterG uses its technology to lower your body weight. The treadmill ranges from 100% weight equivalence all the way down to 20% (this level feels like you’re jumping around on the moon — I’ve tried it!).

Using the AlterG

A View “Under The Hood” shows the air displacement the AlterG uses to lower your body weight.

How do you use an AlterG?

Getting “zipped in” to the AlterG may seem a bit scary, however we assure you it’s totally painless. Furthermore, it’s a bit of an exhilarating experience for new users. After all, who doesn’t want to feel like they’re running around on the moon? The AlterG requires an outfit addition to start. A special pair of pants designed to create the tightest vacuum seal possible are outfitted on top of your existing clothes. Once the pants are on, you’re all set to use the treadmill.

Once you’re outfitted properly, your physical therapist adjusts the height of the machine to match your hip bones. The machine begins to calculate your body weight and calibrate for whatever workout you’d like to complete. The treadmill fills entirely with air in order to calculate your body weight before slightly deflating. This is an interesting experience, making it a bit difficult to touch your heels to the ground in the process! Once the AlterG is fully calibrated, you’re set to work out!


All zipped in and ready to go!

What are the benefits of using the AlterG?

When the AlterG removes the weight from your joints, it lessens the stress on your legs and knees while exercising. In situations where injuries have occurred and healing has begun, the affected areas are sensitive to movement, so it’s important to treat your body’s weight load properly. 

Your physical therapist can adjust the AlterG to change body weight based on your specific recovery needs. By doing so, we are providing the perfect amount of relief and activity during sessions. Your physical therapist can personalize the treadmill based on your specific medical needs and physician's orders. Moreso, your physical therapist will tailor it to your body’s own tolerance to ensure you’re meeting your exercise goals. Some patients require 60% gravity for a proper workout, while another requires 20%.

Using the AlterG

Using the AlterG.

Conditions the AlterG is useful for include:

  • Total Hip or Total Knee Replacements
  • Meniscus Repair
  • ACL Reconstruction
  • Arthritis
  • Stress Fractures
  • Ankle Sprains
  • Parkinson’s Disease
  • Stroke Rehab
  • Traumatic Brain Injury
  • Fall Prevention
  • Cerebral Palsy
  • Multiple Sclerosis

Book Your AlterG Experience

If you’re interested in using the AlterG and would like to learn more about the benefits of the treadmill, feel free to book an appointment today at your local Agile Physical Therapy. We currently have an AlterG treadmill in our Palo Alto and San Mateo locations.

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