If you really think calculations are required for that... I have some bad news for you. Imagine a course that has a sharp uphill for literally only 100 meters at the beginning followed by an even distribution of that elevation gain with a downhill for the rest of the course. Is that not faster than the same course with an equal amount of time spent running uphill vs downhill? My problem with this thread is that everyone is throwing around calculations to support claims about uphill and downhill running without understanding how important the distinction between how the uphills and downhills are distributed is. But just keep talking without actually saying anything I guess, just like everyone else on this thread,