长短者，脉之部位也。气血有余，指下势盛，尺寸皆溢，是谓之长。气血不足，指下势
促，尺寸不及，是谓之短。故脉长者，恒兼洪大滑疾；脉短者，恒兼虚弱细微。此多属于其
人禀赋，而凭脉辨证，即随之以决虚实焉。
长短二脉，合寸关尺三部而言。长者寸尺皆过于本位，短者寸尺皆不及本位，是以关部
无所谓长短之象。昔人每谓关不诊短，以寸关尺三部，本是一线贯注，不能离异，故有寸不
至关为阳绝，尺不至关为阴绝之说。然则关部即不当有短脉，亦必不能以长脉论矣。又阳气
上盛之病，脉长于寸，即短于尺；相火下盛之病，脉长于尺，即短于寸，则所谓上鱼入尺之
脉。偏盛于上者，必短于下；偏盛于下者，必短于上，与专论长短之合寸尺而言者不同。凡
病而得长脉，若非其人之体质素强，则病魔之势焰方张也，或虚阳之浮露于外也。若更长而
不实，长而无神，则形似有余，而其实不及，非佳兆矣。凡病而得短脉，若非其人之体质素
弱，则气血之俱衰也。否则实邪凝结于中，而气道不舒也。若复短而无神，形气俱馁，更难
图矣。故肿疡脉长，无非阳邪之势盛；而肿疡脉短，则为大毒之坚凝。若在溃后，脓毒已泄
，气血已伤，于脉宜敛，则短者似尚合宜，长者必多变幻。苟非毒邪之不减，即其元气之外
浮，所谓证虚脉实，皆当顾虑。惟脉短终是正气不周，津液既耗，而脉应之。滋液养阴，是
为正治。若其短涩无神，则真阴欲竭，亦自可危。
长短，是指脉象在寸、关、尺三个部位上的分布范围。气血充盛，指下感觉气势旺盛，寸部和尺部都超过正常位置，这叫做长脉。气血不足，指下感觉气势短促，寸部和尺部都达不到正常位置，这叫做短脉。所以长脉，通常兼见洪大滑疾的特征；短脉，通常兼见虚弱细微的特征。这种情况多与人的先天禀赋有关，而通过脉象来辨别证候，随即就可以判断虚实的性质了。
长短二脉，是结合寸、关、尺三部而言的。长脉表现为寸部和尺部都超过了本位（正常范围），短脉表现为寸部和尺部都达不到本位，因此关部无所谓长短之象。古人常说关部不诊察短脉，因为寸、关、尺三部，本来是一线贯通的，不能分离异变，所以有“寸脉不到关部为阳绝，尺脉不到关部为阴绝”的说法。既然这样，关部即使没有短脉，也必然不能用长脉来论述了。另外，阳气上盛的疾病，脉象在寸部显得长，而在尺部就显得短；相火下盛的疾病，脉象在尺部显得长，而在寸部就显得短，这就是所谓的“上鱼际、入尺中”的脉象。偏盛于上方的，必然在下方显得短；偏盛于下方的，必然在上方显得短，这与专门讨论长短脉结合寸、尺两部而言的情况是不同的。凡是患病而得到长脉的，如果不是这个人平素体质强壮，那就是病邪的气势正盛，或者是虚阳浮越于外。如果脉更长而且不实，长而没有神气，那么形似有余，其实却不足，这不是好兆头。凡是患病而得到短脉的，如果不是这个人平素体质虚弱，那就是气血俱衰。否则就是实邪凝结在中焦，导致气机不畅。如果脉短而且没有神气，形体和气息都衰弱，那就更难治疗了。所以，肿疡阶段脉象长，无非是阳邪气势旺盛；而肿疡阶段脉象短，则是大毒坚凝的表现。如果在溃破之后，脓毒已经排出，气血已经受伤，脉象应当收敛，那么短脉似乎还比较合适，长脉则必然多有变化。如果不是毒邪没有减少，就是元气外浮，所谓“证虚脉实”，都应当加以顾虑。只有脉短终究是正气不能周流，津液已经耗损，脉象随之反映出来。滋养津液、补养阴精，才是正确的治疗方法。如果脉短涩且没有神气，那么真阴将要枯竭，自然也是危险的。
Length and shortness refer to the positional distribution of the pulse at the Cun, Guan, and Chi positions. When Qi and Blood are abundant, the momentum under the fingers is vigorous, with both the Cun (distal) and Chi (proximal) positions overflowing their normal boundaries; this is termed a Long Pulse (Chang Mai). When Qi and Blood are deficient, the momentum under the fingers is hurried and short, with both the Cun and Chi positions failing to reach their normal boundaries; this is termed a Short Pulse (Duan Mai). Therefore, a Long Pulse is invariably accompanied by characteristics such as Surging (Hong), Large (Da), Slippery (Hua), and Rapid (Ji); a Short Pulse is invariably accompanied by characteristics such as Weak (Ruo), Deficient (Xu), Fine (Xi), and Minute (Wei). This condition mostly belongs to an individual's constitutional endowment, and by differentiating syndromes based on the pulse, one can subsequently determine the nature of deficiency or excess.
The concepts of Length and Shortness are discussed in relation to the three positions: Cun, Guan, and Chi. A Long Pulse manifests as both the Cun and Chi positions exceeding their respective standard locations, while a Short Pulse manifests as both the Cun and Chi positions falling short of their standard locations; thus, there is no concept of length or shortness regarding the Guan (middle) position. Ancients often stated that the Guan position does not diagnose shortness, because the Cun, Guan, and Chi positions are originally connected in a continuous line and cannot be separated; hence, there is the theory that "if the Cun pulse does not reach the Guan, it is Yang Extinction; if the Chi pulse does not reach the Guan, it is Yin Extinction." Consequently, even if the Guan position should not exhibit a Short Pulse, it certainly cannot be described as a Long Pulse either. Furthermore, in diseases characterized by excessive upward movement of Yang Qi, the pulse is long at the Cun but short at the Chi; in diseases characterized by excessive downward movement of Ministerial Fire (Xiang Huo), the pulse is long at the Chi but short at the Cun. This refers to the pulse phenomenon known as "reaching the fish-mound (Yumen) and entering the Chi." Those biased toward excess above must be short below; those biased toward excess below must be short above. This differs from the specific discussion of Length and Shortness concerning the combination of Cun and Chi positions. Whenever a disease presents with a Long Pulse, unless the person has been constitutionally strong since youth, it indicates that the pathogenic factor is currently vigorous, or that Deficient Yang is floating outward. If the pulse is longer yet empty, long yet lacking Shen (Spirit/Vitality), although it appears to have excess, it actually lacks substance; this is not a favorable omen. Whenever a disease presents with a Short Pulse, unless the person has been constitutionally weak since youth, it indicates that both Qi and Blood are declining. Otherwise, it signifies that Excess Pathogens are coagulating in the middle jiao, causing the Qi mechanism to be unsmooth. If the pulse is short and lacks Shen, with both form and Qi being depleted, treatment will be extremely difficult. Therefore, in the stage of swelling/ulceration, a Long Pulse indicates merely the vigor of Yang pathogens; whereas a Short Pulse during swelling/ulceration indicates the firm coagulation of severe toxicity. However, after the ulcer has ruptured, when pus and toxins have been discharged and Qi and Blood have been injured, the pulse should contract/restrain. In this context, a Short Pulse seems more appropriate, while a Long Pulse would likely indicate many variations. Unless the toxic pathogens have not diminished, it implies that Yuan Qi (Original Qi) is floating outward. The situation where "the syndrome is deficient but the pulse is excess" requires careful consideration. Ultimately, a Short Pulse signifies that Zheng Qi (Upright Qi) is not circulating fully, and the pulse reflects the consumption of Jin Ye (Body Fluids). Nourishing fluids and nourishing Yin is the correct treatment method. If the pulse is short, choppy (Se), and lacks Shen, it indicates that True Yin is about to be exhausted, which is naturally dangerous.