体象 牢在沉分，大而弦实；浮中二候，了不可得。
深居在内之象也。故树本以根深为牢，盖深入于下者也；监狱以禁囚为牢，深藏于内者也。仲景曰∶
“寒则牢固。”又有坚固之义也。
主病 牢主坚积，病在乎内。左寸牢者，伏梁为病。牢在左关，肝家血积。左尺得牢，奔豚为患。
右寸牢者，息贲可定。牢在右关，阴寒痞癖。右尺得牢，疝瘕痛甚。
牢脉所主之证，以其在沉分也，故悉属阴寒；以其形弦实也，故咸为坚积。积之成也，正气不足，而邪气
深入牢固。心之积，名曰伏梁；肝之积，名曰肥气；肾之积，名曰奔豚；肺之积，名曰息贲；脾之积，名曰痞气。
及一切按之应手者曰 ；假物成形者曰瘕；见于肌肉间者曰 ；结于隐癖者曰癖。经曰∶“积之始生，
得寒乃生，厥乃成积。”故牢脉咸主之。若夫失血亡精之人，则内虚而当得革脉，乃为正象；若反得牢
脉，是脉与证反，可以卜短期矣。
按沈氏曰∶“似沉似伏，牢之位也。实大弦长，牢之体也。牢脉不可混于沉脉、伏脉，须细辨耳。沉脉如绵
裹砂，内刚外柔，然不必兼大弦也。伏脉非推筋至骨，不见其形。在于牢脉，既实大，才重按之便满指有
力，以此为别耳。”叔和云∶“似沉似伏，犹不能作画一之论也。”吴草庐曰∶“牢为寒实，革为虚寒，安可混
乎？”伪诀云∶“寻之则无，按之则有。”但依稀仿佛，却不言实大弦长之形象，是沉脉而非牢脉矣。又曰∶
“脉入皮肤辨息难。”更以牢为死亡之脉，其谬可胜数哉！
【体象】
牢脉位于沉取部位，脉形宽大、弦直且充实有力；在浮取和中取两个层次，完全感觉不到它的存在。
这是深藏于体内的征象。所以树木以根深蒂固为“牢”，因为它深入地下；监狱以关押囚犯为“牢”，因为它深藏于内部。张仲景说：“寒邪则使脉气牢固。”这里又有坚固的含义。
【主病】
牢脉主要主病为坚硬的积聚，病变部位在体内。左寸部出现牢脉，是伏梁病的征象。牢脉出现在左关部，是肝脏的血积。左尺部出现牢脉，是奔豚病的祸患。
右寸部出现牢脉，可以确定为息贲病。牢脉出现在右关部，是阴寒导致的痞块癖积。右尺部出现牢脉，是疝气和瘕聚疼痛剧烈。
牢脉所主的证候，因为它位于沉取部位，所以都属于阴寒；因为它的形态弦而充实，所以都是坚硬的积聚。积聚的形成，是因为正气不足，而邪气深入并牢固结聚。心的积聚，名叫伏梁；肝的积聚，名叫肥气；肾的积聚，名叫奔豚；肺的积聚，名叫息贲；脾的积聚，名叫痞气。
以及一切按压时手下有感觉的叫做“积”；假借实物成形（指无形之气聚散无常）的叫做“瘕”；显现于肌肉之间的叫做“癥”；结聚于隐蔽部位的叫做“癖”。医经说：“积聚的开始生成，得到寒邪才产生，气机逆乱才形成积聚。”所以牢脉都主这些病症。如果是失血或耗伤精液的人，体内虚弱应当出现革脉，这才是正常的脉象；如果反而出现牢脉，这是脉象与证候相反，可以预测其寿命不长（短期死亡）。
【按语】
沈氏说：“似沉似伏，是牢脉的位置。实大弦长，是牢脉的形体。牢脉不能混同于沉脉和伏脉，必须仔细辨别。沉脉像棉里裹砂，内刚外柔，但不一定兼有大的弦象。伏脉如果不推筋至骨，就看不见它的形状。而在牢脉中，既然实大，只要稍微重按，满手都有力感，以此作为区别。”王叔和说：“似沉似伏，还不能说是完全一致的定论。”吴草庐说：“牢脉主寒实，革脉主虚寒，怎么可以混淆呢？”伪诀中说：“寻取则无，按取则有。”但这只是模糊不清，并没有说出实大弦长的形象，这是沉脉而不是牢脉了。又说：“脉搏进入皮肤难以分辨呼吸。”更把牢脉当作死亡的脉象，这种谬误难道能数得完吗！
[Body and Image]
The Lao pulse (Firm Pulse) is located in the deep (Chen, 沉) level; its form is large, wiry (Xian, 弦), and solid (Shi, 实). It cannot be detected at all in the superficial (Fu, 浮) and middle (Zhong, 中) levels.
This represents an image of residing deeply within. Therefore, trees are called "lao" (firm/deep-rooted) because their roots go deep into the earth; prisons are called "lao" because they imprison people deep inside. Zhang Zhongjing said: "Cold causes firmness." Here it also carries the meaning of solidity.
[Primary Diseases]
The Lao pulse primarily indicates hard accumulations (Jian Ji, 坚积), with the pathology located internally. If the Lao pulse appears at the Left Cun position, it indicates the disease of Fu Liang (Voluminous Beam). If the Lao pulse appears at the Left Guan position, it indicates blood accumulation in the Liver. If the Lao pulse is obtained at the Left Chi position, it portends Ben Tun (Running Piglet).
If the Lao pulse appears at the Right Cun position, it confirms Xi Fen (Breath Accumulation). If the Lao pulse appears at the Right Guan position, it indicates Pi Pi (Epigastric Mass) caused by Yin cold. If the Lao pulse is obtained at the Right Chi position, it indicates severe pain from Shan Jia (Hernia and Masses).
The syndromes indicated by the Lao pulse, because it is in the deep level, all belong to Yin Cold; because its form is wiry and solid, all are hard accumulations. The formation of accumulations occurs due to deficiency of healthy Qi (Zheng Qi, 正气) and the deep, firm penetration of pathogenic factors. The accumulation of the Heart is named Fu Liang; the accumulation of the Liver is named Fei Qi (Fat Qi); the accumulation of the Kidney is named Ben Tun; the accumulation of the Lung is named Xi Fen; the accumulation of the Spleen is named Pi Qi.
And those that feel responsive upon palpation are called "Ji" (Fixed Accumulation); those formed by borrowing material shape (intermittent masses) are called "Jia" (Wandering Mass); those appearing between muscles are called "Zheng" (Solid Mass); those knotted in hidden areas are called "Pi" (Hidden Mass). The Classics state: "Accumulations begin to generate when they receive Cold, and become fixed when Qi rebels." Thus, the Lao pulse governs all these conditions. However, for persons who have lost blood or exhausted essence, internal deficiency should present with a Ge pulse (Leather Pulse), which would be the correct image; if instead a Lao pulse is obtained, this is a contradiction between pulse and syndrome, indicating a short life expectancy.
[Commentary]
Mr. Shen said: "Resembling both Chen and Fu pulses is the position of the Lao pulse. Solid, large, wiry, and long is the body of the Lao pulse. The Lao pulse must not be confused with the Chen pulse or the Fu pulse; careful differentiation is required. The Chen pulse is like sand wrapped in cotton, rigid inside and soft outside, but it does not necessarily combine largeness and wiriness. The Fu pulse is invisible unless pushed to the bone. In contrast, with the Lao pulse, since it is solid and large, as soon as moderate pressure is applied, strength fills the fingers; this is how they are distinguished." Wang Shuhe said: "Resembling both Chen and Fu pulses cannot be treated as a uniform conclusion." Wu Caolu said: "Lao indicates Cold-Excess, while Ge indicates Deficiency-Cold; how can they be confused?" The Pseudo-Mantra states: "Sought lightly, it is absent; pressed, it is present." This is merely vague and does not describe the solid, large, wiry, and long image; it describes a Chen pulse, not a Lao pulse. It further states: "The pulse enters the skin, making respiration difficult to distinguish," and even more erroneously treats the Lao pulse as a pulse of death. How numerous are such fallacies!