The tempo, long, recovery and hill run all serve a purpose that I can relate to and understand. I totally get how each contributes to any gain in performance I achieve. The slow easy run however just feels like a complete waste of time. On the very rare occasion I’ve attempted one, it left me feeling cheated, flat and just plain lazy. In layman’s terms what possible physiological benefits are there in a 10 km run at 1 minute per km slower than goal marathon pace?
Makes no sense to me at all.