The scifit ifi ac5000 treadmill is one of the strongest and most durable treadmill available this is used in many different ways from helping someone improve their fitness to rehabilitating someone after an injury or illnessthis machine has maintenance free shock absorbing technology on the deck the scifit ifi ac5000 treadmill is an excellent machine that is perfect for people with limited leg movements or who are recovering from all sorts of injuriesthe side handrails switch for speed and e