I haven't used to Sled this large since I was running track professionally and I'm pleased to be reunited.This Sled is absolutely awesome. The adjustable height feature really sells it for me cuz this wasn't something that was available for the sleds I trained with. This is truly how you get those glutes and those quads to a size that's respectable, let's not forget about the hamstrings.Now I will say if the weight is anything above 45 lb drive phase is everything so make sure those first few steps are powerful and low and that should push you the rest of the way depending on how far you're going. If you're pulling the sled I would say 50 to 100 m is a good distance. If you're pushing it I would say stick to 20 to 50.I used to sled outside so I coated it in rhino liner just to protect the metal. I would suggest you do the same if you're planning on using it in that fashion.I'm Very pleased with the sled.Until We Meet Again-Off the Grid Ken