Obliques

Obliques: what are they?

External oblique runs from the lower ribs downward and forward to the pelvis and the midline; internal oblique lies beneath it with fibres running the other way. Because of that crossing arrangement, the external oblique on one side works with the internal oblique on the other to rotate the trunk. Every throw, swing, punch and change of direction uses that diagonal pairing. In the gym they are usually trained with side bends, which is close to the least useful thing you can do with them.

What they do

The obliques rotate the trunk, side-bend it, and assist trunk flexion when both sides work together. They also contribute to raising intra-abdominal pressure, so they are part of the bracing system alongside transverse abdominis.

The action they perform most often is resisting. In a carry, one side stops the trunk falling sideways. In a single-arm press or row, they stop it twisting. In running, they control the rotation the arms and legs generate. This anti-rotation and anti-lateral-flexion work is where most oblique training in a sensible program lives.

How to train the obliques

Cover three things across a week: resisting rotation, resisting side-bend, and producing rotation under control. The third is where power athletes need the most work and general clients need the least.

Side bends and the wider waist myth

Loaded side bends are the classic oblique exercise and they are not dangerous, but they train a short range in one plane and skip the anti-rotation work that transfers to sport. If a client only has time for two oblique exercises a week, a suitcase carry and a Pallof press are a better use of them.

The claim that oblique training widens the waist deserves a plain answer. The obliques are thin sheets of muscle and heavy training does not visibly broaden a waistline in most people. Waist width is set by rib cage and pelvis structure and by body fat. Train the obliques for what they do; do not avoid them for a cosmetic reason that does not hold.

What goes wrong in practice

The first pattern is rotation that comes from the lumbar spine. The lower back has limited rotation available and the thoracic spine has much more. A client who twists hard and feels it in the low back is usually rotating where they should not be. Set up so the ribs turn on a stable pelvis, and check thoracic rotation range before loading rotational work.

The second is a Pallof press done with the arms rather than the trunk. If the client can extend and return the arms while the ribs quietly rotate, the exercise is doing nothing. Slow the movement, reduce the load, and watch the belt line rather than the hands.

The third is a side-to-side gap that nobody checks. Side plank hold times and suitcase carry distances often differ noticeably between sides in clients with a one-sided sport or job. Test both, then train to the weaker side.