Forearm Side Plank (Modified)
This side plank rests on the forearm and the bottom knee, with the trunk and thigh lifted into one line. Bending the bottom leg shortens the lever, so beginners can hold a genuinely good position long enough to actually train the obliques. Coached by Maddy (NASM-CPT) — these are the exact form cues he gives on every client's first week.
Muscles worked
Sets & reps by goal
| Goal | Sets × Reps | Rest |
|---|---|---|
| Strength | 4 holds × 15-20 sec per side | 60 sec |
| Muscle | 3 holds × 25-40 sec per side | 45 sec |
| Endurance | 2 holds × 45-60 sec per side | 30 sec |
Level — Beginner
Beginner — the standard entry to side-plank work; the knee-down base is a feature, not a compromise.
Proper form — 5 cues
- Stack the elbow directly under the shoulder before anything lifts.
- Bend the bottom knee to 90 degrees behind you, thigh staying in line with the body.
- Lift the hip until the shoulder, hip and bottom knee form one straight line.
- Press the floor away through the forearm — never hang in the shoulder socket.
- Stack the top shoulder and top hip vertically, with no forward roll.
Breathing: Slow, even breathing throughout the hold — the ribs keep moving while the waist stays lifted.
The 3 mistakes Maddy corrects most
Common questions
Is the kneeling side plank still worth doing?
Absolutely — the obliques and the deep side-trunk muscles work the same way, just against a shorter lever. For a beginner, thirty good seconds here builds more than ten collapsing seconds of the full version. It also remains useful later as a high-rep or long-hold option on lighter days.
When do I progress to the full side plank?
A practical gate: hold this version for forty-five seconds per side with the hips never dipping and the chest never rolling forward. Then progress in stages — extend the top leg first while the bottom knee stays down, and only afterwards straighten both legs into the full stack.
Why does one side feel dramatically weaker?
Side-to-side differences in trunk endurance are close to universal — daily habits, old injuries and dominant-hand patterns all contribute. Start every session on the weaker side while you are fresh, match the stronger side's time to the weaker side's result, and the gap typically closes over several weeks.
Related exercises
Harder: Side Plank Hold
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