#90: 100 Sledgehammer Strikes (Against a Tire)

Few movements feel as primal or as productive as swinging a heavy hammer against a giant tire.

The sledgehammer strike blends rotational force, grip strength, cardio conditioning, and mental focus into one violent but controlled movement. It’s as close to old-school hard labour as you’ll get in the gym, and that’s exactly why it’s one of our top RB100 challenges.

In Challenge #90, you’ll complete 100 full-power strikes, alternating sides and maintaining form throughout.

“Grip it. Rip it. Reset. There’s nothing more honest than a hammer strike.”
- RB100.Fitness

Challenge Rules

• Reps: 100 total
• Equipment: Sledgehammer (6–12kg) and a large tractor tire
• Form Guidelines: Use rotational swing from shoulder to hip
• Alternate sides every 5–10 strikes
• Hit centre of tire with full control
• Maintain posture and core stability

Suggested Set Options

• 10 × 10 with short rest
• 5 × 20 alternating every 5 reps
• EMOM: 10 strikes per minute for 10 minutes
• Max effort: 100 for time (track it in the RB100 Tracker)

Why It Works

Sledgehammer training is a rotational power developer that mimics real-world movement mechanics — chopping, swinging, striking — while building the kind of functional strength few isolation lifts ever touch.

Muscles Worked:

• Forearms and grip
• Core and obliques
• Shoulders and traps
• Glutes and hips (through rotation and stance)

It’s also a brilliant stress relief tool, giving you a satisfying outlet that doubles as power cardio.

Technique Tips

• Lead with hips and shoulders, not just arms
• Keep your eye on the tire - don’t swing blind
• Pivot back foot slightly to allow rotation
• Reset grip between sets to avoid slipping
• Breathe rhythmically: inhale on pull-back, exhale on strike

Scaling & Progressions

• Beginner: Use a lighter hammer (4-6kg) and take longer rest
• Intermediate: Standard 6-8kg hammer, alternating sides
• Advanced: 10kg+ hammer, unbroken reps, minimal rest
• Add footwork for athleticism or combine with battle rope rounds
• Pair with #64: 100 Battle Rope Slams for a total upper-body finisher

Programming Ideas

This works well as:

• Finisher after strength days
• Warm-up for rotational sports (e.g. rugby, MMA)
• Recovery tool when done light and rhythmic
• Partner challenge: 50 reps each for time

Recovery & Mobility

Expect fatigue in grip, traps, and abs. Recover with:

• Wrist mobility drills
• T-spine rotations
• Forearm release with ball or band
• Hydrate as always via #23: 100oz Water Daily

Learn More

• Kettlebell Kings: Sledgehammer Conditioning Workouts
• Kettlebell Kings: Why Every Athlete Should Train with a Hammer