The 3 races will slow down your aerobic progress, but the period of aerobic base training in between races will help maximize your rest and recovery. (philmaffetone.com)
We recommend to start with 2 - 3 weeks of aerobic base training working up to 60 - 120 minutes steady state. (vespapower.com)
This is good practice for athletes of all disciplines as even building strength and power is better accomplished when a strong aerobic base is in place. (marksdailyapple.com)