在东汉，内丹学尚未出现，但承接着老庄的打坐方法是有的。【太平经】提出【守一明法】是守一功到达境界后，明便会出现，明是光明，智慧的意思。【太平经】又提出人体内精气神三宝，建立三合一的修炼模式，有【爱气尊神重精】之说。
五代陈搏(即陈希夷)教人练丹的金句是【炼精化气，练气化神，练神还虚】，往下又影响着魏华存夫人所传的【黄庭经】、【存思】，以及葛洪的【抱朴子】的【守一】等论述。这影响更延至近代清—吕祖乩文【太乙金华宗旨】的【守一回光】都是一脉相承。
近几十年道教内部流传一幅修炼图叫【内景图】又名【内经图】，实缘自两篇吕祖乩诗。揭露内丹修炼的重点：有形之气如何转化无形之丹炁。这幅图本是清初道人所画，后来光绪年间，被一位叫素云道士刘诚得到，发现此图非常可贵，便发心付梓印制，时年公元一八八六年，木板印制，后由北京白云观收藏。
【吕祖全书】卷四文集中载有两首律诗分别是：
【铁牛耕地种金钱，刻石儿童把贯串。
一粒粟中藏世界，半升铛内煮山川。
白头老子眉垂地，碧眼儿童手指天。
若向此中玄会得，此玄玄外更无玄。】
【我家勤种自家田，内有灵苗活万年。
花似黄金苞不大，手如白玉颗皆圆。
栽培全赖中宫土，灌溉须凭上谷泉。
只候九年功满日，和根拔入大罗天。
（功课一朝成大道，逍遥陆地水蓬仙）】
上述律诗隐喻周天运行法（河车路）；气在督脉与任脉互不相连的经脉中，循环运行的轨道途径：【气】经修炼后由下丹田产生的【人气】经丹田而出经由督脉的【尾闾穴】向上运升，经【命门】过【夹脊】攻玉枕，至头顶【泥丸宫】，然后向前而下，过【印堂】降【重楼】调【中丹田绛宫】，纳入【下田丹】。在修炼过程中，有大小河车之别，小河车即小周天在立基百日之内运行，大河车即是大周天在坎离之后再运行。
外国最近兴起的【能量黄医学】说人体本身是各种能量的结合体；包括物理能量、生理能量、心理能量。又说：生命存在于一个活的有机体中，而这有机体必然是一个能与体外交换能量与物质开放系统。生命体必须有外来能量的持续输入，始能保持体内结构的秩序性。
上述描述与和道家内丹学将人体分为精、炁、神各层级，透过意识提升为手段，积聚能量，转化能量等不谋而合。又近代科学家测知，脑波分为许多等级，各个等级的脑波频率不同。由此得知，精气神修炼的公式，会造成脑能量的改变，其功能又各有不相同。
据元代道士李道德在【中和集—试金石】一书所学举，当时传统的练功方法有三千多种，从道书上找到有根据的至少也有二百多种，大致可分为十大类：
一、炼神 二、调气 三、守竅 四、存思 五、内丹
六、導引 七、辟谷 八、服食 九、撮生 十、房中术
与炼气有关最早出土文献，距今二千四百多年前，战国初年流行的练气方法【行气玉珮铭】；即说：【行气：深则蓄，蓄则伸，伸则下，下则定，定则固，固即萌，萌则长，长则退，退则天。天机舂在上，地机舂在下，顺则生，逆则死。此铭文可称为内丹修炼最原始的工夫，（一）有哲学含意，【天机舂在上，地机舂在下，】即天覆地载，气的周游在一封闭虚间中（橐籥）发生。
（二）有炼【丹】之意，【定则固，固则萌，萌则长】应指呼吸之气新成，即是后所指【真炁】或【丹】的概念。
其次，也是说，练气的过程，像一棵树的生长过程一样，先往地里向下扎根，待根扎稳了，再往上萌生，往天空发展长出枝叶。
【行气玉珮铭】其修炼主要是：吸气胀肚，提肛束勒阳关，藉由呼吸从外界吸进来的阳气上具有电能、热能、磁能，性刚烈躁动，它在身体里是很不安定，要控制它并不容易。犹如任何电器，火电很凶猛，万一漏电就会伤人，但能接上地线，相对比安全，同样地，丹田里的阳气，累积到一个程度，也会变得凶悍，所以也要将它道入地下。这就是老子说的【人法地，地法天】，魏伯阳的【参同契】书中一句：【从头流达足，究竟復上升】即是说明，练气必须下行入地再反弹上来，这是练气最重要的诀窍。
练武的筑基功夫是扎马步（即行拳的樁步），其目的是导气入地。科学家实验得知，身体的任何部位用劲或紧张，该部位皮肤电位就会升高，显示气会往身体用劲或紧张的部位流动。扎马步时身体重心下移，只有脚步用劲上身放松，下肢的气脉逐渐打开，气就会由上往下，流经湧泉入地。曰：功深，身上的气会与地气结合在一起，下盘便会变得非常稳固。人身上各有一个穴道接天接地，接天的穴道是灵台，接地的穴道是阴窍，阴窍位于会阴之上。现代解剖学则成为前列腺。前列腺素在生殖、消化、循环、代谢等方面，具有复杂的生理及药理作用。阴窍又名生死窍，復命关，为奇经八脉的总根。上通灵台，下通湧泉，是精炁的转运站，此窍一通，诸脉皆通。因此，【张三丰大道指要】说【调息者，调度阴窍之息，与吾心中之气，相合于气穴中也】。
基本上，武术家的守窍与修道者的守窍方式也不一样。修道者守窍日的在转化能量，而练武守窍目的在增加能量，武术家说：【丹田者力之府也。欲精技击必健丹田】。武术家之内力来自丹田，他们必须历经【气到丹田→气满丹田→气壮丹田】的步骤加以锻炼，使丹田达至【气充于中力贯于外】的境界。
武术家所谓之内气，即如【乐育堂语录】说：【虎者猛物也坎中之空阳之气。此气纯阳，阳者易动，有如虎之难防，此气则最刚，有如虎之难制，惟龙之下降可以伏此虎也】。武术的内力即是阳之动能，但是阳难以控制，所以要进行练气化精，精练化炁同练的步骤，服气兼伏炁，使得精炁合一，用炁来控制精使其安定，精气就能乖乖的听命。武术家有句行头语：【练成丹田混元气，走遍地下无人敌】。
武术之内力，其中要诀在于动静之分，因为任脉主静，其功能吸纳能量；而督脉主动，其功能在运用能量。即是说以丹田聚气，以仙骨发气。仙骨位于督脉的根部，经常锻炼仙骨，可以补充脊髓、脑髓的能量，让神经系统反应敏锐快速。
中國武學會 / 會長
王銳勳
二零一七年四月五日
In the Eastern Han Dynasty, the al-Jaram did not appear yet, butthere are some ways to undertake the meditation of Lao-tzhuang. The TaipingScripture argues that "keeping onecouldunderstand the meaning" means that once a person reaches a state ,truthwill emerge. It means being bright and wise. [Taiping Jing]also proposed the essence of the human three treasure, theestablishment of three in one mode of practice, there is [love energy, respect mind,seriousoriginality ]Taiping Jing said.
Fivegenerations dynasic Chen Tuen (Chen XiYi) teach people to practice Dan's golden sentence is [refinement of energy,practice energystrongmind, practicing mindbecome origin ], it affect Mrs. WeiHuacun's biography [Huang Ting-jing], [keeping mind] , As well as Ge Hong[Baopuzi] [keep one] and other expositions. This effect is more extended tomodern Qing - Lu Zu Wen [TaiyiJinhua purpose] [keepingone become light back]are the same strain.
[Lu Zu whole book] Volume IV anthology contains two verses are: 【Ox arable for money, string together by inscribedchildren. Chestnut pack a world, halfliter Sheng boiled mountains. Old man eyebrow touch ground . blue eye child point the sky,if you can get this mystery, this mysterious is the only one. 】
My family diligently fieldtheir own, there are a smart sprout livemillion years. Flowers like gold bud is not big, hand as white jadeare all round. Cultivated in the palace soil, irrigated by upper Spring. As long as nine years of full life, and rootinto the big Luo sky. (effort into the avenue, Happy like a Daoist Immortal)]
Metaphor of regularverse as above, mentioned operation of the inner energy circler (River track); energy in the meridians andveins unrelated , circulation orbital pathways: [energy]from “dantin” producedby practice. [acquired energy] Outthrough the “tok”vein of the [coccyx cave] move up, cross the [life gate/ ming mun]over [chest behind/Jiaji] pushing back of head/yun jang, to the top [mud pillPalace/ni yuen], and then move forward, down cross [between the eyebrows/YinTang] down [multi-floor/chun lau】adjust【middle dantin/hon palace】, into the 【bottom dantin/lower abdomen】. In the process of cultivation, there is a difference between Smalland large river pathway . small one runs on the basic build period in a hundreddays. The large one runs after brain and energy combine under practice .
Recently, the rise of foreign countries 【Energy Huang Medicine】that the body itself is a combination of various energy; including physicalenergy, physiology energy, mental energy. Added: Life exists in a livingorganism, which must be an open system of exchanging energy and matter with theoutside world. The living body must have continuous input of external energy,beginning to maintain the order of the body structure. The above description and the Taoist inner alchemy divided thehuman body intoEssence, Energy, Brain , through awareness raising as a means toaccumulate energy, transforming energy coincide. And modern scientists measuredthat the brain waves are divided into many levels, different levels of brainwaves of different frequencies. From this we can see that the formula of therefined energy cultivation will result in the change of the brain energy andits function will be different from each other.
According to Li Daode of Yuan dynasty in [Zhonghe Set –golden test stone],a book was printed. At that time, there were more than 3,000 traditional waysof practicing work. There were at least 200 kinds of evidences found fromDaoists, which could be broadly divided into Ten categories:
First, refining brain Two, adjust breathing Three, focusing the orifices Four, pondering Five, the inneralchemy Sixth, guiding, Seven,go on hunger strike Eight, external energy eating,Nine, regimen Ten, healthy sexes.
The earliest unearthed literature related to refining, dating backover 2,400 years ago, the popular method of practicing qigong in the earlyWarring States Period [line gas Jade Emperor carved]; that is: [gas: deep savings, storage extension, extension Then,the next is fixed, fixed become solid, solid becomelife,life becomegrow, after back, then return base. Natural from universe, anotherby earth, follow would alive ,opposite would dead .This inscription can be called the most primitive timeof inner alchemy practice, because (a) there isphilosophical implication, [text means covered with universeand earth, the gas travel flow through virtual room (橐籥)occur.B) there is refining [Dan] meaning, [fixed become solid, solid becomelife,life becomegrow]shouldrefer to the breath into new energy, that is, after referring to the [true energy炁] or [Dan] concept. Second, it also means thatthe process of practicing qi is like the process of growing a tree. It mustfirst go down to earth and take root, stabilize it and then grow up to grow itsbranches and leaves in the sky.
[line gasJade Emperor carved] its practice is mainly: inflatable blisters belly,mention the ancillary Le Yang Guan, breathing from the outside world by theintake of yang with electrical energy, heat, magnetic energy, base stiff agitation, It is very unstable and it is not easy to control. Like any electrical appliances, thermal power is very fierce in case ofleakage will hurt, but can be connected to the ground, relatively safe, in thesame way, the pubic region yang, accumulated to an extent, will becomeaggressive, so also Drive it underground
This is what Lao Tzu said [human follow rule, rule follow natural], Wei Bo Yang's [参同契refining method ] book in a: [from scratch to reach foot, return after reach ] is to show that training must be down to the ground andthen rebound up, This is the most important trick to practice.
By: Mr AlexanderWong Yui Fan
Presidentof : The Institute of Chinese Martial Arts
2017-4-05