Workout Description

Why This Workout Is Medium

While the individual elements are moderately challenging (70/53lb KB swings, 200m runs, 10cal AB), the 1-minute rest between rounds prevents significant fatigue accumulation. The movements don't interfere significantly, and the volume per round is manageable. The workout will take 25-35 minutes but the 1:1 work-to-rest ratio allows sufficient recovery. Most average CrossFitters can maintain consistent pacing throughout.

Benchmark Times for The Furnace

• Elite: <22:00
• Advanced: 24:00-26:00
• Intermediate: 28:00-30:00
• Beginner: >45:00

Training Focus

This workout develops the following fitness attributes:

• Endurance (8/10): Ten rounds of mixed cardio modalities with running and assault bike creates significant cardiovascular demand, though 1-minute rests prevent maximal endurance challenge.
• Stamina (7/10): Repeated rounds tax muscular endurance, particularly in posterior chain and legs. Rest periods allow partial recovery between efforts.
• Speed (6/10): Quick transitions between modalities and maintaining high output on short intervals is key, though rest periods reduce overall speed demand.
• Power (5/10): Kettlebell swings develop hip power, while running and bike efforts require moderate power output for acceleration phases.
• Strength (4/10): Moderate-heavy kettlebell weight requires decent strength, but movement pattern and rep scheme emphasize endurance over max strength.
• Flexibility (3/10): Russian kettlebell swings require basic hip hinge mobility and shoulder flexibility, but movements are not technically demanding.

Movements

• Air Bike
• Run
• Kettlebell Swing

Scaling Options

Run: Reduce to 150m or substitute 200m row/ski erg Assault Bike: Reduce to 7-8 calories or extend time cap Kettlebell: Scale weight to 53/35 lbs or 35/26 lbs based on ability. Focus on hip hinge technique Rounds: Reduce to 6-8 rounds for newer athletes Rest: Extend to 90 seconds if needed for appropriate work:rest ratio Time Cap: 40 minutes

Scaling Explanation

Scale if unable to maintain proper KB swing mechanics for all rounds, if run pace slows significantly after round 5, or if unable to complete bike calories in under 30 seconds consistently. Priority is maintaining intended stimulus of moderate-intensity aerobic work with good movement patterns. Athletes should finish in 25-35 minutes with relatively consistent round times. Scale load/volume to achieve this time domain while keeping intensity appropriate.

Intended Stimulus

Moderate-length aerobic conditioning workout (25-35 minutes) with mixed modal elements. Primary focus is oxidative energy system with brief glycolytic spikes. The 1-minute rest intervals allow for incomplete recovery, testing aerobic power and recovery capacity. The workout challenges both cardiovascular endurance and muscular stamina.

Coach Insight

Maintain consistent pacing across all 10 rounds - this is not a sprint. Target 1:45-2:15 per working round. Keep runs at 80% effort. On assault bike, quick but controlled start then settle into sustainable pace. For KB swings, sets of 5+5 or unbroken if possible. Common mistakes: sprinting early rounds, rushing transitions, letting swing form deteriorate. Use rest minute for full recovery - catch breath and reset mentally. Success requires disciplined pacing strategy.

Benchmark Notes

Breaking down this 10-round workout with mandatory rest: Per round: - 200m Run: 35-45s (fresh state) - 10 cal Assault Bike: 15-20s - 10 KB Swings: 20-25s - Transitions: ~10s - Mandatory 1 min rest: 60s Base round time: ~130-150s including rest Fatigue progression: Rounds 1-2: 130s (base) Rounds 3-4: 140s (1.1x) Rounds 5-6: 150s (1.15x) Rounds 7-8: 160s (1.2x) Rounds 9-10: 170s (1.3x) Total projected time for elite athletes (L10): ~1500s (25:00) This workout is most similar to Kelly (5 rounds of running + 2 other movements) but with twice the rounds and mandatory rest. Using Kelly's anchor points (L10: 15:30-17:30) and doubling for rounds while accounting for forced rest: L10: 22:00-24:00 L5: 30:00-32:00 L1: 45:00-50:00 Female times adjusted 10-15% slower due to heavier KB weight relative to body weight and slightly slower run/bike pacing.

Modality Profile

Run and Bike are both monostructural (M) cardio movements, while Kettlebell Swing is a weightlifting (W) movement. With 2 M movements and 1 W movement, the breakdown is approximately 70% monostructural and 30% weightlifting.

Similar Workouts to The Furnace

If you enjoy The Furnace, you might also like these similar CrossFit WODs:

• Assault Bulldozer (83% similar) - AMRAP in 20 minutes 20 calorie Assault Air Bike 15 Wall Ball Shots (20/14 lb) 10 Sumo Deadlift High ...
• Helen (82% similar) - For time: 3 rounds: 400 meter Run 21 Kettlebell Swings (53/35 lb, 1.5/1 pood, American) 12 Pull-Ups...
• Blackjack (Assault) (82% similar) - AMRAP in 21 minutes 21 calorie Assault Air Bike 21 Kettlebell Swings (53/35 lb) 21 AbMat Sit-Ups...
• BNCP (82% similar) - AMRAP in 20 minutes 1,990 meter Bike Erg 4 Front Rack Lunges (135/95 lb) 5 Thrusters (135/95 lb)...
• French (82% similar) - For Time 1 mile Run 50 Deadlifts (185/135 lb) 1 mile Run 3 minute Max Burpees...
• Dumbbell Demons (82% similar) - 5 Rounds for Time 5 Single Arm Dumbbell Snatches (75/40 lb) 10 Dumbbell Lunges (75/40 lb) 15 GHD Sit...
• Open 19.1 (81% similar) - AMRAP in 15 minutes: 19 Wall Ball Shots (20/14 lb) to 10/9 ft target 19 calorie Row...
• Officer Jason Knox (81% similar) - Buy-In: 54-second moment of silence Then, AMRAP in 20 minutes: 5 Dumbbell Deadlifts (2x50/35 lb) 6 ...

These WODs similar to The Furnace share comparable training demands, time domains, and movement patterns.