Primary Muscles
Core (rectus abdominis, transverse abdominis, obliques), hip flexors
Cardio
Mountain Climber
Driving knees to chest in plank position — the cardio+core hybrid that spikes heart rate fast.
3D animation — watch the full movement
Secondary Muscles
Shoulders (deltoids), chest, triceps (stabilisers), quadriceps, cardiovascular system
Equipment
None (bodyweight)
Location
Home / Gym / Park
Difficulty
Beginner → Intermediate (with speed)
How to Do It
- Start in a high plank position. Hands directly under shoulders, body in a straight line.
- Core braced, hips not sagging or piked. Gaze at the floor, neck neutral.
- Drive the right knee toward the chest fast — knee doesn't touch the ground.
- As you pull the left knee in, extend the right leg back — mimic a running stride.
- Tempo: beginner 30 sec slow alternating, advanced 30 sec sprint. 3-5 rounds, 30 sec rest between.
Common Mistakes
- Piking the hips upward (V shape) — core disengaged, only legs are working.
- Sagging lower back — back pain, spinal load.
- Hands drifting forward — support point is unstable.
- Knee touching the floor — injury risk, breaks the form.
- Holding the breath — cardio impact drops, lightheadedness possible.
Beginner Tips
- Start with static plank — 30 sec × 3 sets for position endurance.
- Slow mountain climber: 1 second per knee drive. Speed up once form is locked.
- 30 sec active + 30 sec rest, 5 rounds is plenty to start.
- For hard cardio: 20 sec sprint + 10 sec rest (Tabata-style) × 4 rounds.
Frequently Asked Questions
How many calories does mountain climber burn?
For a 70 kg person at high tempo: ~10-12 kcal/min — 10 min = 100-120 kcal. With HIIT afterburn, total day count can hit 150-180 kcal.
Will it build abs?
Activates abs (especially lower abs + obliques), but not enough alone for hypertrophy. Crunch + plank + leg raise combos are more effective. Mountain climbers are cardio + core endurance.
Can someone with knee issues do this?
At slow tempo on a padded floor, usually safe. With patellar issues, don't let the knee touch and reduce range. Avoid during acute injury — consult a clinician.
Related Exercises
Push-Up
The bodyweight classic — works chest, shoulders, triceps and core in a single compound movement.
Russian Twist
The classic oblique isolation move — rotational core strength and the V-cut taper.
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