Engine #12B

18 minutes work, 2 minutes rest, 2 rounds. Divide athletes into 2 zones: treadmills and ski ergs. Each zone has 18 minutes of work with 90-second transitions. This week completes a 4-week progression. Zone 1: 2 paces - Tempo and High End Threshold; run 90-second efforts aggressively. Tempo recoveries are shrunk to 90 seconds; 6x 90-second efforts before transition. Zone 2: Timed Ski erg effort; any athletes can pair up. “I Go, You Go” intervals; each athlete completes 9 rounds. Athletes self-time their intervals. 90-second gap between the first and second 18-minute efforts for transitions