Modified Plank (Forearm, Knees)
Builds anterior core endurance and overall trunk stability in a position that reduces lumbar spine loading compared to a full plank, making it an appropriate entry point for core strengthening.
Duration
5 minutes
Calories
12-18 kcal
Reps × Sets
Hold for 15-30 seconds × 2-3 sets
Rest
30-45 seconds between sets
Benefits
Muscles Involved
Rectus abdominis, Transverse abdominis, Shoulder stabilizers, Gluteals
Equipment Required
Exercise Mat
Step-by-Step Instructions
- 1Start on your forearms and knees, elbows under shoulders.
- 2Engage your core and lift your knees slightly off the floor, or keep them down for an easier version, forming a straight line from your knees (or hips) through your head.
- 3Hold this position without letting your hips sag or pike upward.
- 4Lower with control when the hold is complete.
Breathing: Breathe normally and continuously throughout the hold.
Common Mistakes
- Letting the hips sag toward the floor as fatigue sets in
- Holding the breath during the hold
Safety Tips
- Stop the hold as soon as form starts to break down, rather than pushing to a longer time with poor technique
Contraindications — Do Not Do This Exercise If
- Active cauda equina red flags
- Recent abdominal surgery, before surgeon clearance
- Wrist or shoulder pathology limiting weight-bearing
Stop Immediately If
- Sharp lower back pain
- Significant shoulder pain
Progressions
Harder (Progression)
Lift the knees fully off the floor for a full forearm plank, or extend the hold duration.
Easier (Regression)
Perform against a wall in a standing incline position, or hold for a shorter duration.
Scientific Evidence
Modified plank variations are widely used as a graded entry point into core endurance training, consistent with standard rehabilitation progression principles moving from stability-focused exercises (bird dog, dead bug) to sustained isometric holds.³
A genuinely useful bridge between basic stability exercises and more demanding core work. — Dr. Vishal Nigam
Frequently Asked Questions
Related Exercises
References
- 1. North American Spine Society Section on Interdisciplinary Spine. Therapeutic exercise following lumbar spine surgery: a narrative review.
- 2. American College of Obstetricians and Gynecologists. Committee Opinion No. 804: Physical Activity and Exercise During Pregnancy and the Postpartum Period.
- 3. American Physical Therapy Association. Clinical Practice Guidelines: Neck Pain (2017); Patient Education: Core Strengthening for Spine Health; Shoulder Impingement and Postural Exercise.
- 4. American Academy of Orthopaedic Surgeons. Clinical Practice Guideline: Management of Osteoarthritis of the Knee; OrthoInfo: Thoracic Spine Conditions, Hip Impingement.
- 5. World Health Organization. 2020 Guidelines on Physical Activity and Sedentary Behaviour.
- 6. American College of Sports Medicine. Position Stand: Resistance Training Prescription for Muscle Function, Hypertrophy, and Physical Performance in Healthy Adults (2026); Guidelines for Exercise Testing and Prescription — Flexibility Recommendations.
- 7. North American Spine Society. Patient Education: Understanding Sciatica; Diagnosis and Treatment of Degenerative Lumbar Spinal Stenosis.
- 8. World Health Organization. 2020 Guidelines on Physical Activity and Sedentary Behaviour — Older Adult Recommendations.
- 9. Carenyx Knowledge Library. Understanding Slip Disc (01-understanding-slip-disc.md); Understanding Sciatica (02-sciatica.md) — reused directly, not re-derived.