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A fully trained Thai Masseur will ask you many questions about your health and want to know whether you have any physical or mental conditions you’d like help with. Your answers (alongside other factors such as your gender and body type) will determine how and where your practitioner will apply pressure and stretches to your body. In the Thai medical system, conditions such as low energy, chronic pains and illness are associated with blockages or breaks in specific pathways in the body. These pathways are known as the ‘Sen’.

Depending on which teacher you follow, the Sen may be described as purely energetic phenomena, or they may be seen as corresponding directly to anatomical structures. But either way, unblocking these pathways during a massage brings greater flow and freedom of movement in the body, giving the receiver an overall sense of well-being and an energised calm.

A Thai Masseur works along these pathways, using their hands, feet, forearms and elbows to apply pressure to your body. The lines also need to be stretched. To achieve this, your practitioner will use their whole body and through balance, counterweight and gravity to lengthen and loosen your muscles and connective tissues.


What are Sen?

This is the tricky part. There is no general agreement between practitioners and schools on exactly what the Sen are or on the paths they take through and across the body. There are said to be 72,000 lines but most people are familiar with just ten of them, the Sip Sen. There is at least some general agreement about the paths of the Sip Sen through the body.

Contrary to Western style massage, traditional Thai massage does not primarily work with the physical body but rather with the energy body of man.

Harald Brust  (Asokanada) History of traditional Thai Massage

The diagram on the left (Or 13922, f. 32) indicates the channels and main pressure areas of the body, stylistically represented by spiralling calligraphic lines. One channel known as pinkhalā, for instance, begins at the navel and proceeds past the base of the right leg to exit via the back. Another channel, the susumannā line proceeds from the navel into the chest, climbs through the body and exits through the tongue.

Here the pressure point above the right eye is identified as the one for treating pains and infections of the eye as well as dizziness. In the middle of the forehead is a point for treating headaches, fevers and congestion of mucus and haemorrhage in the nasal passage. (Or 13922, f. 36)


Physical structures or energetic pathways?

In her book Thai Massage: Sacred Bodywork, Ananda Apfelbaum explains that there’s no satisfactory English translation of ‘Sen’ so we need to use an array of words to describe the concept. These include conduit, channels, fibres, filaments, narrow ridge, line, sinew and tendon. ‘Sen’ is also a prefix for anatomical Thai words for ‘lymphatic’, ‘blood vessel’, ‘artery’ and ‘vein’. Apfelbaum suggests that the best English word to use would be ‘conduit’. This encourages us to think of flow and movement through the body rather than specific anatomical structures.

Ananda Apfelbaum Source

Different teacher, different interpretation

The different lineages and schools of Thai massage vary quite dramatically in their approach to the Sen. Until you understand this, it is very confusing to be a new student trying to learn them – because the answer you get depends on whom you ask.

Here are some quotes from established teachers on how they interpret the Sen:

For our intentions, my favorite explanation is that a Sen is a “physical pathway by which movement occurs in the body.”

For the most part, Sen are tangible structures. Most of the Sen that we work with in the body are tendons, ligaments, veins, nerves and arteries. They also also sometimes refer to muscular and fascial pathways.

Nephyr Anne Jacobson in her book Traditional Thai Medical Theory for Bodyworkers, Findhorn Press 2015.

Thai texts mention red, black and white Sen. which correlate roughly with arteries, veins and nerves. However, the main Sen used in Thai massage seem to correlate most strongly with networks of myofascial tissue (which structural integrations call the ‘anatomy trains’). The lines for the most part follow the grooves in between muscles, connecting important insertion points to one another.

Dr. C. Pierce Salguero and David Roylance in their book Encyclopedia of Thai Massage — A Complete Guide to Traditional Thai Massage Therapy and Accupressure, Findhhorn Press 2011

The word ‘Sen’ in the Thai language means string, or pathway. It is the movement of energy along these channels that maintains health. The ‘Sen Sip’ are the most important channels in the human body….
The body is a vehicle to access the human energy system, so relying entirely on anatomy to find the lines can create confusion. Where there is injury, illness or damage to the body, the sen can change their qualities. Maps and line charts cannot show you exactly where the individual Sen lie; this is something you must feel and sense and learn when you touch your client’s body.

Felicity Joy in Thai Massage and Thai Healing Arts by Bob Haddad, Findhorn Press 2013

Flow of energy* in the body

Energy flows freely around a normal, functionally healthy body. Every second, you are consciously and unconsciously perceiving your environment and responding to the feelings and impulses that arise from your perceptions.

If you feel love for the person you are with, you will direct your energy towards the person, your relationship and your feelings for them. In this state, you often have a certain glow, and can be quite magnetic — other people will generally feel good around you. If you are fearful, your energy will be directed towards defence, protection and escape. When you are sad, the energy will be focused on the source of the pain — so it will be directed inwards, towards the experiencer of the pain.

When these emotional states become chronic, the energy that is normally only temporarily directed to a transient state gets stuck. Most of us are familiar with people who seem to be fixed in a state of defence or attack, or who seem locked into a state of overwhelm or low energy — and we have probably experienced this ourselves. Our body initially responds appropriately to the situation: it’s good to defend yourself and loved ones against an external threat, and resting when you’re tired and stressed is the right thing to do. Problems arise when these responses become chronic, remaining long after the threat or stress has passed. When this happens, the flow of energy around the body declines and this is expressed as habitual tension patterns, imbalances, constricted movement and poor posture.

*The word ’Energy’ in this context is rather meaningless, but there isn’t a good substitute that includes both the mental phenomenon of attention and the physical condition of ease of movement in the body. In a healthy state we can easily shift our attention from one activity to another and maintain it when necessary; we can move our physical body fairly easily. When we are more challenged, attention is rigid and stubborn or so flighty we can’t achieve anything and our bodies don’t easily respond to what’s required of them — perhaps fidgeting and unable to stay still, or so heavy and slow that even the tiniest movement seems like a monumental effort.

‘Lom’ and blocked or broken Sen

In place of the non-specific ‘energy’, the correct term to use in Thai Massage is Lomor Lom Pran. This is similar to chi in Chinese medicine and prana in yogic systems. If this flow of Lom is in any way impeded by blockages or breaks in the Sen, you will experience less-than-optimum health.

Long-held tensions in muscles and connective tissues – as described above – can result in such blockages.

Breaks in the Sen can be caused by injuries such as sprains and tears in connective tissue.

The goal of Thai Massage is to correct the Lom imbalances by stimulating the affected Sen to  activate the body’s natural healing process and thereby restore your full function and vitality.

According to Tom Myers of, posture is the result of a complex interaction between genes, life experience, imitation of parents or significant others in early life and sometimes injuries. So it’s important not to make overly simplistic, presumptive interpretations of a person’s state just by observing them on a superficial level.
Ananda Apfelbaum,
Please note that information about how Sen work is used to treat injuries and illnesses applies to Thai Medicine and medical massage. It is provided for information only and is not intended to make any claims for the efficacy of my treatments.

The Sip Sen or Sen Sib

Of the 72,000 Sen, only ten — the Sip Sen — are well understood by practitioners and used in general Thai Massage. The Sip Sen include:

  • Sen Sumana
  • Sen Kalathari
  • Sen Itta and Pingkhala
  • Sen Sahatsanangsi and Thawari
  • Sen Lawusang and Ulangka
  • Sen Khitchanna and Nanthakrawat

As I said above, each teacher and school sees the Sen differently, so no single map of the lines can be taken as a definitive truth. Some traditions will include just a single main line, while others will include numerous branch lines extending from the main line.

Here’s a sketch of one interpretation of the paths of each of the Sip Sen:

Sip Sen - Source:

The Sen and other Eastern Healing Modalities

Sen and TCM Meridiens

Just like the nature and map of the Sen, there is plenty of variation on whether the Sen are similar to the lines used in other modalities or whether they should be each be regarded as their own complete systems.

Whoever is familiar with the Meridians in Chinese acupuncture or with the system of the Prana Nadis in Yoga will find lots of similarities. All the chakras, the main energy centres in the yoga tradition are covered. I’m personally very much convinced that all these different traditions have the same origin and background that the differences we find today are of minor importance. Anyway, whatever system of energy lines you use in your work, it is based on the experience of hundreds of years — and it does work.

Asokananda (Harald Brust), The Art of Traditional Thai Massage, Editions Duang Kamol 1990

Ananda Apfelbaum agrees, on the basis of geography, history and migration, Buddhism, Ayurveda, Chinese medicine and yogic traditions must have intermingled and influenced one another.

But Nephyr Anne Jacobsen is very clear that the Sen are their own system and part of the Traditional Thai Medicine, and should not be confused with TCM meridians. The Sen begin in the navel area and end at the extremities of the body, such as the finger tips, toes and head. Unlike the Chinese meridians, the Sen do not correspond to  certain organ functions.

Kam Thye Chow, who was a student of Asokanada, agrees that the fundamental difference between the Sen system and traditional Chinese medicine (TCM) is that TCM relates energy (Chi) to specific organs. The names and application of the meridians reflect this, so you have lung meridians, heart meridians and so on.

Here’s a map of the TCM meridian for comparison:

Sen and Ayurveda

Chow integrates the Sen system with Ayurveda and says that the practice is focused on balancing the Tridoshas. These are Vata (air), Pitta (fire) and Kaptha (Earth) which provide an orientation on a person’s fundamental mental and physical nature.

Thai Yoga Therapy for Your Body Type: An Ayurvedic Tradition by Kam Thye Chow, Emily Moody, David Frawley (Foreword by)

Sen and Prana Nadis

Nāḍī (Sanskrit: नाडी, lit. ‘tube, pipe, nerve, blood vessel, pulse’) is a term for the channels through which, in traditional Indian medicine and spiritual knowledge, the energies such as prana of the physical body, the subtle body and the causal body are said to flow. Within this philosophical framework, the nadis are said to connect at special points of intensity, the chakras.[1] The three principal nadis run from the base of the spine to the head, and are the ida on the left, the sushumna in the centre, and the pingala on the right.

The nadis play a role in yoga, as many yogic practices, including shatkarmas, mudras and pranayama, are intended to open and unblock the nadis. The ultimate aim of some yogic practises are to direct prana into the sushumna nadi specifically, enabling kundalini to rise, and thus bring about moksha, or liberation.


From this quote, you can see how initially similar the concepts of Nadis and Prana are to the Sen and Lom. But there is a fundamental difference: the Sen are part of the Thai medical system where the line you work depends on the complaint you want to address. For example, bronchitis and other respiratory conditions require the practitioner to work Sen Sumana, as do upper digestive tract and diaphragmatic complaints such as acid reflux or hiccups.

This medical aspect obviously doesn’t apply to a normal therapeutic or wellness Thai massage, where the practitioner aims to treat the whole body and is unlikely to have training in the Thai medical system.

Thai Medicine as a complete system

Nephyr Anne Jacobson in her book ‘Seven Peppercorns, Traditional Thai Medical Theory for Bodyworkers’, describes every aspect of the Traditional Thai Medicine. The Sen share the stage with Thai Element theory, herbology and spirit medicine. When performing Thai massage, the aim is not to release tightness in the physical structures but to move the lightest element – wind – though the body.

Seven Peppercorns: Traditional Thai Medical Theory For Bodyworkers


My intention here is not to settle any arguments on the nature of the Sen and how they run across and through the body. Nor is it debate whether Sen should be mixed with meridians or Nadis. I am a beginner in this practice and could not add much value to this debate. What I do want to do is highlight the variety of approaches taken by different teachers and traditions.
As a student of Thai massage and while researching this article, I found myself tied up in knots of confusion and frustration — until I let go and realised that there aren’t any ‘facts’ to be found. What every teacher says with absolute consistency is that you must develop your own sense of the Sen through years of practice and close attention to your client. The dearth of facts and certainties simply reflects the practice’s origins as a hands-on therapeutic healing massage.