BL56 Support the Sinews

Reviewed by · Licensed Acupuncturist & TCM Physician · Last reviewed June 2026

BL56 (Chengjin, “Support the Sinews”) is an acupuncture point on the Bladder Meridian. It is located on the posterior aspect of the leg, in the center of the belly of the gastrocnemius muscle, 5 cun inferior to BL54 (Weizhong). It relaxes sinews, invigorates channels, alleviates pain.

Location

On the posterior aspect of the leg, in the center of the belly of the gastrocnemius muscle, 5 cun inferior to BL54 (Weizhong).

Needling

Perpendicular insertion 1 to 1.5 cun. Caution for small saphenous vein.

TCM functions

Relaxes sinews, invigorates channels, alleviates pain.

Indications

Spasm of the gastrocnemius, hemorrhoids, low back pain.

Clinical notes

Chengjin is a key point for relaxing the sinews and invigorating the channel in the calf region, making it highly effective for muscle cramps, spasms, and pain in the gastrocnemius. It is also useful for sciatica, leg paralysis, and hemorrhoids, often paired with BL57 for synergistic effect. Its name, 'Support the Sinews,' directly reflects its primary function in treating sinew-related disorders.

On the Bladder channel

BL56 is one of 67 points on the Bladder Meridian. Nearby points:

Frequently asked questions

Where is BL56 located?

BL56 (Chengjin) is located on the posterior aspect of the leg, in the center of the belly of the gastrocnemius muscle, 5 cun inferior to BL54 (Weizhong).

What is BL56 used for?

BL56 relaxes sinews, invigorates channels, alleviates pain. Common clinical indications include spasm of the gastrocnemius, hemorrhoids, low back pain.

How is BL56 needled?

Perpendicular insertion 1 to 1.5 cun. Caution for small saphenous vein.

Which meridian is BL56 on?

BL56 is a point on the Bladder Meridian (Zú Tài Yáng Páng Guāng Jīng).

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⚠️ This page is for general education and is not medical advice. Acupuncture is a traditional practice; evidence varies by condition and study quality, and individual results differ. It does not replace diagnosis or treatment by a licensed professional. Always consult a qualified acupuncturist or physician.