Side Plank

• Obliques
• Intermediate
• Timed — 20 seconds per set

The side plank stacks the body sideways on one forearm and holds the hips high — the standard test and builder of oblique strength.

In the 30-day plan it is always scheduled as a pair, left side then right, and the weaker side sets the time for both. Hips sagging toward the floor is the one mistake that undoes the whole hold.

How to do it

1. Lie on your side, forearm under your shoulder.
2. Lift your hips so your body forms a straight line.
3. Hold steady and keep your core braced.

Breathing: Slow, even breaths.

Common mistakes

• Rolling the bottom foot flat onto its sole instead of holding its outer edge.
• Turning the supporting forearm across the body instead of pointing it forward.
• Letting the waist sag toward the floor so the body bends at the hip.

Form tips

• Press the bottom shoulder down away from your ear so you do not sink into the joint.
• Squeeze the glutes to keep the hips forward, since they drift back as the hold gets hard.
• Pad the supporting elbow with a folded towel if the floor digs into it on longer holds.

Muscles worked

Alternatives with the same focus

• Bicycle Crunches
• Bent-Knee Windshield Wipers
• Heel Touches

Where it appears in the 30-day plan

Programs in the app that schedule this movement:

• Core & Abs
• Love Handles