The deck on a running machine can absorb a huge amount of shock from your joints. See how treadmill cushioning works, and find out if the better treadmills have more cushioning in their decks. Full range is at http://www.fitonline.com.au/treadmills/

See more gym equipment reviews and videos at http://www.fitonline.com.au/buyers-guides/ and on the FitOnline.com.au Youtube Channel.