What it trains
Both aerobic and anaerobic capacity, depending on the day of the block. Aerobic sessions sit in a moderate intensity band for longer intervals, training stroke volume and the ability to clear metabolites between efforts. Anaerobic sessions use shorter, harder intervals with incomplete recovery, training lactate tolerance and the buffering that goes with it.
Physically it loads the legs and hips heavily through sleds and bikes, the upper back and grip through carries and rowing, and the trunk continuously. The long-term adaptation most members notice first is not on the bike; it is that the third set of a Strength session stops feeling like the third set.