A treadmill includes a tread deck supported on a tread base, and one or more cushioning members disposed below and engaged with the tread deck for cushioning the tread deck and for absorbing impact loads imparted on the tread deck by the users, the cushioning member includes different resilience for...http://www.google.co.uk/patents/US7163493?utm_source=gb-gplus-sharePatent US7163493 - Treadmill having changeable suspension
