Here's the Science: Theorem for Replacing Uphill Riding with Driving for Endurance Conditioning: as Published in "Conditioning the Gaited Horse for Endurance 2" 2016

The question is often posed: do you need hills to condition a horse for endurance riding?
There has been a suggestion that having your horse “drive” will simulate hills. I don't believe there is science to back up this speculation, it sounds good but I think is quite impractical for most people and may not actually work. There is science to test if this is true or not. In this short article, Nancy Morgan Reed works with a mechanical engineer to find the solution using math, physics and a bit of trigonometry. The solution may be surprising, but it often is when we apply real math to a situation most normally evaluated anecdotally.