This 12-week Base Phase plan is designed for Cat 1 and Cat 2 riders at intermediate to advanced levels who are looking to build a strong foundation of fitness and strength on the bike. The focus is on developing aerobic capacity, muscular endurance, and overall resilience through structured endurance, tempo, and sweet spot work, with supporting strength and cadence sessions. Riders will progressively accumulate training load across the weeks to enhance efficiency, durability, and race readiness, while maintaining balance with recovery to ensure sustainable performance gains. Upon successful completion, athletes may wish to continue their progression by moving onto our Mesopo 12-Week Build Phase Plan for Cat 1 & 2 to further develop race-specific fitness and performance.