I have been trying out various treadmills at the clubs I'm going to and I am wondering why I feel like I am gliding on air on some of them while others feel like I'm truding through sand.


I don't just mean cushining but on some treadmills I amd able to easily run my normal 20 minutes at 7.5 or so.

While others I am barley able to get past 10 minutes at 6.5 without feeling like I am going to die.

Just trying to figure out what gives or am I just nuts

You just said it...cushioning. If a treadmill doesn't have proper cushioning, it will increase the amount shock to your joints. Also, some treadmills in a commercial setting have motors that will automatically adjust the speed to be more comparable to your natural motion (you never run at a constant speed, but treadmill belts moves at a constant speed).