PhysioUpdate 1st August 2022


Using NASA's Differential Air Pressure Technology within Neuro & Orthopaedic Rehab

Partial weight bearing- how do we measure it and how do we ensure consistency? Differential Air Pressure technology provides an effective way to carry out precise partial unweighting.


What is Differential Air Pressure (DAP)?

“Differential air pressure (DAP) is a pressurised, variable lifting force used to decrease the impact of gravitational forces and body weight during walking, running, or exercise. DAP is frequently used in various physiotherapy applications for safely training and rehabilitating patients.”

AlterG Anti-Gravity Treadmills use the NASA developed patented technology to provide “Differential Air Pressure” (DAP) in the form of a “bubble” on a treadmill. This enables patients to be unweighted from 100% down to 20% in precise 1% increments, precise partial weight bearing at its finest.

How do patients benefit from using DAP?

At its core, DAP enables patients to exercise during rehabilitation without the fear of pain or re-injury and without compromising the natural gait and form crucial to proper rehabilitation.

In addition, patients can safely rehab with confidence in a fall safe environment, support motor learning and enable functional activity and task-specific training.

AlterG DAP v Underwater Treadmills and Pools

Water will always have a place in rehabilitation, for example, rehabilitation of upper limbs, it is easier to increase heart rate when running in water due to the difficultly pushing against the viscosity of the water.

However, there is a very good reason to use AlterG’s DAP technology over water, which includes:

  • Possibility to use the AlterG after day one of surgery without the risk of water affecting any surgery/infection risk.
  • Accurately unweight from 100% down to 20% of their body weight in 1% increments. If you are lucky to have a pool with a moving floor you can still only unweight between 20% to approximately 50% and not accurately.
  • Muscle firing patterns and ground reaction forces mimic walking normally unlike water where you push through the viscosity of water and the faster you walk the more buoyant you become.
  • Running costs are key and the cost of running a pool or underwater treadmill is significantly more than the running cost of an AlterG.
  • AlterG can be used unattended, where appropriate, unlike water where you need at least one if not 2 people to help, maximising physiotherapists time.

SportsMed Products Ltd are proud to distribute AlterG Anti-Gravity Treadmills in the UK & Ireland with more than 200 machines installed to date within NHS & Private Hospitals, private physio clinics, charities, government bodies and professional sports.

Louis O’Connor Clinical Lead at the Regional Trauma Unit at the Royal Victoria NHS hospital said “We are enabling people that can’t walk to walk, we are enabling people to run that can’t run”

The AlterG Via Model now comes complete with easy step-up access, live video monitoring, pain scale, pre-programmed workouts and reporting tools. Enquire today about rental, leasing options (subject to approval) and purchase options of the AlterG and provide the latest technology to your patients.

Did you know many of our physio clinics now rent their machines out to local clubs, patients and other physios by the minute? The AlterG can be a great tool for providing additional income for the clinic and rehabilitation to your local community.

Contact sales@sports-medical.co.uk for more information.



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