Learn locust pose (Salabhasana): variations A and B, what studies measure in back, pelvic floor and shoulder blades, and how to lift without a hollow back.
How high do you need to come up in locust pose, and isn't it just a hollow back? The honest answer: You hardly need to come up, and a hollow back is exactly the mistake. Locust pose (Salabhasana) is a strength exercise for the back: lying on your belly you lift chest and legs off the floor, with arms behind (variation A) or pointing forward (variation B).
The muscles behind it have been measured. In an ultrasound study of 52 healthy people (aged 28 to 68), the back muscles became thicker in the pose: the long back muscle (longissimus) grew by about 1.4 times, the iliocostalis and the multifidus by about 1.2 times, the quadratus lumborum by about 1.2 times [2]. Anchor: Your long back muscle becomes roughly 40% thicker in the pose, so it is clearly working.
The pelvic floor works too: in an EMG study the pelvic floor (levator ani) reached about 63.5% of its maximum voluntary contraction in locust pose, well above "side angle" (35.3%), modified side plank (29.1%) and hands-clasped front plank (26.3%) [1]. Anchor: That is nearly two thirds of what it can do at maximum. And with arms forward the activity of the shoulder blade muscles was highest among 15 poses (lower trapezius 56.8%) [3].
How hard is locust? Beginner-friendly if you start small. It is the stepping stone to the bow pose (Dhanurasana).
Lie on your belly, legs hip-width, arms at your sides, palms up or down. The forehead rests on the floor.
First lift only the chest a few centimetres and hold 3 breaths. Then lower the chest and lift only the legs a little, again 3 breaths. Your gaze stays on the floor, the neck long.
Milestone: You manage both parts for 3 breaths each without a pinch in the lower back.
Lift both at the same time, arms pointing back. The pubic bone stays on the floor, the legs stay active, the glutes loose. It is not about height but about keeping the back long. Hold 3 to 5 breaths, lower and repeat two or three times. The pause between rounds is part of the training, not lost time.
If variation A holds cleanly for 5 breaths, stretch your arms forward and lift them too. That way the pose challenges the shoulder blade muscles most [3].
Milestone to move on: 5 breaths in variation A, 3 repetitions, no hollow-back feeling, neck stays soft. Then you are ready for bow pose.
Lower everything, turn your head to the side, rest 3 breaths.
Locust pose is a backbend. Repeated overextension of the lumbar spine is considered a risk factor for stress fractures of the vertebral arch (spondylolysis) in young athletes, mostly at L5 [4]. That is a sports finding, not a yoga finding; locust with small height is not a hard overextension. But if you have back pain on overextension, clear the pose before practising.
The Cochrane review on yoga for chronic back pain found, with low certainty, more adverse events, mainly increased back pain, than with "no exercise" [5]. With pelvic floor complaints, bear in mind that the pose challenges the pelvic floor strongly [1]; clear it beforehand with a physiotherapist or doctor. This guide explains and motivates; it does not replace supervised training or medical advice.
Lift one centimetre less than you can. Then the pubic bone stays on the floor, the glutes loose, and the back extensors carry instead of the lumbar spine buckling. If you hold locust cleanly for 10 breaths, you are further than someone who pops up 20 centimetres in 3 breaths. Practice trick, not study-backed.
Mainly the back extensors: in an ultrasound study of 52 healthy people the long back muscle became about 1.4 times thicker in the pose, the multifidus and iliocostalis about 1.2 times [2]. With arms forward the shoulder blade muscles also work strongly [3].
Not high. If chest and legs are a few centimetres off the floor, the back stays long and the neck relaxed, the pose is fulfilled. The studies did not set height as a goal. More height usually demands more overextension.
It challenges it strongly: in an EMG study it reached about 63.5% of its maximum activity, above "side angle", modified side plank and hands-clasped front plank [1]. With pelvic floor complaints, clear the pose beforehand with physiotherapy or a doctor.
It strengthens the back extensors [2], but the study does not prove that this relieves back pain. The Cochrane review found only small, clinically unimportant improvements for yoga in chronic back pain and more adverse events than with "no exercise" [5].
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