I need some advice on choosing the right treadmill.
Running on the treadmill is my preferred way to stay in shape. Over the years, I have regularly used various treadmills at different gyms and one apartment complex workout room. I would run several times a week at higher speeds for sustained periods. I never had any knee pain from any of the machines I would use. Additionally, I have run for sustained intervals outdoors on the sidewalk/side of the road and have never experienced knee pain.
Last year, I purchased a used treadmill for my home and began regularly doing the same routine. The problem is that after 4 or 5 workouts, I began to have knee pain. I ceased working out like this for a week or so and start again to see if the problem would persist. The knee pain returned. It seems like a safe assumption that the unit's shock absorption isn't sufficient. In summary, with all other factors constant, the treadmill I acquired hurts my knees whereas no other machine had; however, with this problem, I wouldn't be able to be sure of a treadmill with only a 5 minute test run on a showroom floor.
Can someone provide advice on how to find a treadmill with shock absorption well suited for endurance running as well as controlling my cost. I'd like to try to stay under $600.
Are there specific perimeters/features to look for that I can verify per the make/model before buying one?
Are there specific models that someone has used that may be what I'm looking for?
Would a specific retailer or a certain type of retailer be known to give unbiased advice?
Would certain retailers take my old one as a trade-in (not expecting to get a lot)?
If you have the expertise, what would you advise someone in my situation?