I won't be able to ride tomorrow so I did the 4x15 today. Waited until the rain stopped and the headed out in the 46 degree temps. The last 20 minutes it was pouring again. Basically went non-stop on these. Held 291 for 10, 291 for 14, 290 for 10, 290 for 15 and the split the 7 minutes home at 276 and 294. Did 56 of the 60 minutes scheduled. Less than one minute between each.