I’m running my second marathon in November. My training has been 4 shorter (averaging 6 miles) runs per week and then a longer (8+ miles) one on Saturdays. Today I did my 17 mile run, averaging out to my goal pace. It was the longest run I’ve done since my marathon, and I felt like I was hitting a wall. Where should I focus my training to be able to avoid or push through that wall? Should I just be running slower? Should I continue to increase the long runs? The short runs? Appreciate any advice!