How hard is it to put together a treadmill?

Putting together a treadmill can be difficult for those without a lot of DIY experience or the proper tools. The job is easier done with two people and can take a day to complete, which is why hiring a pro who can get it done quickly is often a better use of time. A treadmill assembly professional will know how to assemble it properly and perform trickier steps like lubricating the belt, ensuring the correct tension and not over-tightening screws.