Half Distance Triathlon Boise: Train Smart for Idaho’s demanding 70.3-mile test through Idaho’s diverse terrain. With a 1.2-mile swim in Lucky Peak Reservoir, a rolling 56-mile bike ride through rural outskirts, and a 13.1-mile flat run along the Boise River Greenbelt, athletes face varied physical demands and warm race-day conditions averaging 81°F (27°C). The Senior Triathlete 60+ Half Distance Triathlon Training Plan is built specifically to help experienced athletes age 60 and over meet ...