Base first, then the burn.
Felix ran a 2:28 marathon before he ever wrote a session for anyone else — and the way he trains the room comes straight out of that: aerobic base is earned, not hacked. No magic intervals before the engine exists.
His 07:30 conditioning block is the dawn crew's anchor — steady-state work, breathing drills, the unglamorous miles that make everything above them possible. Then Tuesdays and Thursdays the evening intervals open up, and the east-wall lane gets loud.
Members who stick with Felix describe the same arc every time: it felt easy, then it felt impossible, then one morning it felt easy again — faster. That is the whole sport, compressed.