This session should last 40 minutes. Find a location where you can pick different points on the hill. Lamp posts are great. So for example you would run to the first lamppost and back to the bottom of the hill. Then to the second lamppost and back. Keep making the reps longer until you hit 20 mins, and then start making the reps shorter again.

So you might reach lamppost 12 in 20 mins, then next rep will be to lamppost 11, then 10, then 9 and so on, eventually returning to 1.

Use the downhill as your recovery. You should be working at an RPE of 8 up the hill, and a 3 downhill.

A tough session so important to pace yourself well. If you really want to make it challenge, push the pace downhill as well.