Preface: I am 21yo 6'3 ~235lbs former football player (soccer). I stopped playing because of a leg injury and let myself go but I want to get back into shape. I enjoy running and still have good stamina but my knees are awful and running outside on uneven ground still causes pain.
The problem occurs when I try using a treadmill. I've tested this on four different treadmills and all got nearly the same results. When running faster than a light jog, the treadmills all "stutter". It is almost like the treadmill stops spinning when I put my foot down while running. The four different treadmills all reacted similarly and have a "stutter" when moving faster than a light jog. I have tried looking up what causes this but I haven't found many resources or answers.
It's almost embarrassing for me now thinking my weight is causing this issue but I don't think I'm over the weight limit of the treadmills.
What could be a cause of stuttering/pausing and how do I fix it? It doesn't seem to be equipment related (unless I'm extremely unlucky).