Obliques workout: side planks, hanging raises and the turning exercises, sorted

The obliques are the muscles on the sides of your waist, in two layers: an external oblique on the outside and an internal oblique under it. They turn your trunk, bend it to the side, and resist both when you want to stay still. This page is about training them. It lists the oblique exercises that already have a full guide on this site, says what the studies measured in each, and builds a short session. The front abs, the "abs" most people mean, are on the core workout; this page is for the sides.

Everything below is muscle activity or muscle thickness in a lab session, not growth over weeks, and nothing here is a way to lose fat from your waist: that is a different question.

Side holds

The side plank has the most support. In 13 apparently healthy people, the external oblique was thicker during the side plank than during a bird dog, a glute bridge or a hip extension, and the internal oblique was thicker than during a bird dog or a dead bug.¹ In 30 healthy adults, the authors suggested the side bridge may help strengthen the external oblique, as well as the gluteus medius on the side of the hip.² And in 15 recreationally active men doing a side plank, a side plank with the top leg raised and eight Copenhagen plank variations, the internal oblique showed the most muscle activity of the trunk muscles measured, about 38 to 77% of a maximal contraction.³ The authors concluded the Copenhagen versions, particularly the long-lever and elevated ones, brought greater and more one-sided oblique activity and higher perceived effort. The Copenhagen plank page has the lever lengths.

A front plank is a different hold. In 12 resistance-trained men, external oblique activity did not differ significantly between a plank held to failure with 20% of body mass on the lower back and 6-rep-max back squats, though the squat produced more erector spinae activity,⁴ and in seven men a plank worked it harder than a front squat or an overhead squat.⁵ The plank page has the setup.

Reverse crunches and hanging raises

The obliques also work when the legs come up toward the ribs.

• Reverse crunch and v-sit. In 25 healthy people doing five exercises, the reverse curl and the v-sit produced the most activity in the external obliques.⁶ In 21 people, a reverse crunch on a bench inclined 30 degrees was among the exercises with the highest internal oblique activity.⁷ The guides: reverse crunch and v-ups.
• Hanging raises. In the same 21-person study, a hanging knee-up with arm straps was among the exercises with the highest internal and external oblique activity.⁷ In 14 men, a hanging straight-leg raise put external oblique activity at 88% of a maximal contraction.⁸ The toes-to-bar page builds up to it.

The turning exercises

The Russian twist, the cable woodchopper and the Pallof press are the most familiar oblique exercises, and I can't tell you what they do for the obliques: no study cited here measured oblique activity in any of the three. What the guides cover is what was measured, such as pelvis movement in the Pallof press and power and reliability in the woodchop. They are rotation and anti-rotation work, and they fit an obliques session for that reason, not because a study ranked them.

An obliques session (practical)

This is a practical layout, not a protocol from a study. Put it after your main lifts:

1. Side plank. Two or three holds of 20 to 40 seconds a side. When that's easy, raise the top leg or move to a Copenhagen plank.
2. A reverse crunch or a hanging knee raise. Two or three sets of 8 to 15, slow on the way down.
3. A turning or anti-turning move. Pallof press, woodchop or Russian twist, two sets of 8 to 12 a side.

Stop each set with a rep or two left. (How to judge reps left.) The American College of Sports Medicine's 2026 stand found muscle growth was enhanced by ten or more sets per muscle group a week,⁹ a figure for whole groups, so I don't give an obliques-only count: put your side-plank and raise sets toward your core total, two sessions a week. At home, a side plank, a reverse crunch on the floor and a band Pallof press need no machines.

Common questions

Which exercises work the obliques?

The studies don't rank one as the winner. The side plank has the most support, with the external oblique thicker in it than in several other exercises¹ and the internal oblique the most active trunk muscle across ten side-plank versions.³

Do side bends or Russian twists work the obliques?

No study cited here measured oblique activity in either, so I make no claim for them. Use the side plank and the raises for the sides, and add a twist or a side bend if you like it.

Will an obliques workout shrink my waist?

This page makes no claim about waist size. It is about training the muscles; the belly fat page covers waist questions.

How is this different from the core workout?

The core workout is built around the front abs and what squats already cover. This page is for the sides of the waist: the side plank and its harder versions, the raises, and the turning exercises.

If you'd rather not plan it alone

Three exercises at the end of a workout are easy to write down; fitting them around your lifts and your recovery is the part a page can't do. Coaching is the version where your workouts are built around the days you actually have, and a weekly call looks at the week you just had and rebuilds the next one. Coaching to build muscle explains how that works, and here's how to apply. Otherwise: add two side planks a side to the end of your next workout.