Beginners who step up to Full Distance without a base phase tend to make the same mistake: they try to bridge the volume gap by working harder in week one instead of working longer over several months. That approach usually backfires, either as an overuse injury or as burnout somewhere around week ten.

Couch To IRONMAN Finisher Starts Small. A 140.6-mile race. A 2.4-mile open-water swim, 112 miles on the bike, and a full marathon to finish. If you're sitting on your couch right now — and you haven't laced up your running shoes in years — that number sounds like a different language.