Swedana

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The word ‘swedana’ means providing fomentation or sudation or steam or making a person sweat.[1] It is an important treatment modality among the six primary treatments in Ayurveda. [Cha.Sa.Sutra Sthana 22/4] It is the principal treatment for diseases caused by vitiation of vata and kapha dosha. This treatment is administered before purification therapies (panchakarma). Fomentation therapy essentially includes sweating induced for therapeutic purpose by specific techniques or methods. Thus, it excludes pathological sweating either due to disease or sweating due to environmental conditions.
In ancient times, various sweating methods were applied for the therapeutic purpose by utilization of natural resources. In current times, modified techniques are used to induce sweating, which allows better heat regulation and enhanced therapeutic control. However, both methods are equally effective and can be applied depending upon the availability of resources.

Contributors
Section/Chapter/topic Chikitsa /Panchakarma/ Swedana
Authors Aneesh E.G., Deole Y.S.
Reviewed by Basisht G., Gandhi R.
Affiliations Charak Samhita Research, Training and Development Centre, I.P.G.T.& R.A., Jamnagar
Correspondence email: carakasamhita@gmail.com
Publisher Charak Samhita Research, Training and Development Centre, I.T.R.A., Jamnagar, India
Date of publication: October 04, 2020
DOI 10.47468/CSNE.2020.e01.s09.031

Etymology and derivation

The word ‘swedana’ is derived from Sanskrit root ‘swid’ with suffix ‘dhy’. This means ‘to ripe’ or ‘cook’. It also means perspiration.[2] The therapeutic procedure which relieves obstruction, stiffness, heaviness and cold by sweating is called ‘swedana’. [Cha.Sa.Sutra Sthana 22/11]

The word ‘fomentation’ is used in this article to denote ‘swedana’ therapy.

Classification

Based on inclusion of fire

The fomentation therapy is classified into two categories based on inclusion of fire in the heating techniques. [Cha.Sa.Sutra Sthana 14/65]

A. Inclusion of fire (sagni) in therapy

B. Without using fire (niragni) in therapy

Inclusion of fire (sagni)

There are thirteen methods of fomentation in which fire is used to induce sweating. [Cha.Sa.Sutra Sthana 14/39-40]. These methods utilize natural resources for fomentation making it relatively convenient and cost-effective. These can be used in healthcare practices with the same efficacy as of modern fomentation techniques.[table 1]

Table 1: Various types of fomentation (swedana)
Serial No Name of method Procedure
1 Bolus fomentation (Sankara Sweda) In this method, a bolus of various natural materials (herbs or mud or cow dung or sand) is heated and applied to the affected part. [Cha.Sa.Sutra Sthana 14/41] This is generally used for local fomentation due to predominance of kapha dosha, adipose tissue (meda dhatu), tumors (granthi) and on painful body parts.[A.S. Sutra Sthana 26/7]
2 Lying on a medicinal mattress prepared for the therapeutic purpose (Prastara Sweda) A mattress is prepared with various medicinal materials and covered with silk cloth, woolen pieces or leaves of Ricinus communis (eranda), Calotropis gigantean (arka), etc. After proper oleation (snehana), the individual is advised to lie on this mattress. Generally, corn, pulses, steamed boneless meat (vesavara), sweet porridge, a boiled mixture of pulses and cereals (krishara), etc. are used for preparing the mattress. [Cha.Sa.Sutra Sthana 14/42] This method is used for whole-body fomentation.
3 Steam fomentation using a tube (Nadi Sweda) In this method, fomentation is done by using medicinal steam vapors through a hollow tube. This method is generally used for localized fomentation on a particular body part. [Cha.Sa.Sutra Sthana 14/43]
4 Shower technique for fomentation or affusion (Parisheka Sweda) Medicated liquid is poured or sprinkled or showered slowly and steadily over the body part covered with cloth. [Cha.Sa.Sutra Sthana 14/44]
5 Tub fomentation (Avagahana Sweda) Person is made to sit or lie in the medicated liquid or warm water, neck- or navel-deep. This method is used for whole body and local fomentation. [Cha.Sa.Sutra Sthana 14/45]
6 Fomentation therapy in a chamber (Jentaka Sweda) The person in this method is advised to stay in a specially constructed and circular vaulted chamber for sweating. A pillar-shaped furnace with burning coal is in the chamber room's center to generate heat. It is a type of dry fomentation used for whole-body fomentation. [Cha.Sa.Sutra Sthana 14/46]
7 Fomentation by heated slab of stone (Ashmaghana Sweda) A heated stone slab is used for fomentation. It is used for whole-body fomentation. [Cha.Sa.Sutra Sthana 14/47-49]
8 Fomentation using heat in a trench (Karshu Sweda) In this method, fomentation is done by using a trench filled with burning charcoal. [Cha.Sa.Sutra Sthana 14/50-51]
9 Fomentation in a closed chamber (Kuti Sweda) The person is advised to stay in a specially constructed circular chamber with thick walls and without windows. Heat is generated through furnaces beside the walls. The person is made to lie on a cot in the center and covered with thick blankets. This method is used for whole-body fomentation. [Cha.Sa.Sutra Sthana 14/52-54]
10 Fomentation on heated floor (Bhu Sweda) Here the fomentation is done on a heated floor. [Cha.Sa.Sutra Sthana 14/55]
11 Fomentation with a pot (Khumbika Sweda) In this method, fomentation is done using vapors coming out of a pot with hot medicated liquid. [Cha.Sa.Sutra Sthana 14/56-58]
12 Fomentation in a pit (Kupa Sweda) Cow dung, camel dung, horse dung, etc. are filled in a wide pit and burnt. A traditional Indian bed (charpai or khat) covered with a thin sheet is placed over the pit after burning subsides. The person is advised to lie on the bed for whole body fomentation. [Cha.Sa.Sutra Sthana 14/59-60]
13 Fomentation using a heap of dung (Holaka Sweda) In this method, a wide heap of dung is burnt. After burning subsides, a traditional Indian cot covered with thin sheet is placed over it. The person is advised to lie on the bed for whole body fomentation. [Cha.Sa.Sutra Sthana 14/61-63]

Without using fire (niragni)

There are twelve methods to induce sweating without using fire as heating media. These methods are generally used to reduce kapha dosha and fats (meda dhatu)by enhancing basic metabolism.[Su.Sa.Chikitsa Sthana 32/15]

  1. Physical exercise (vyayama)
  2. Staying in warm chamber (ushnasadana)
  3. Covering with thick coat or blanket(guru pravarana)
  4. Fasting (kshudha)
  5. Excessive intake of alcohol (bahupana)
  6. Fear(bhaya)
  7. Anger (krodha)
  8. Applying bandage (upanaha)
  9. Wrestling(ahava)
  10. Exposing to sunlight(atapa)[Cha.Sa.Sutra Sthana 14/64]
  11. Carrying heavy weights(bhara vahana)[Su.Sa.Chikitsa Sthana.32/15][3]
  12. Walking(adhwa)[Su.Sa.Chikitsa Sthana.32/15][3]

Classification based on form of heat

  • Heat in moist form(snigdha): This is applied in conditions due to vitiation of vata dosha.
  • Heat in dry form(ruksha): This is applied in conditions due to vitiation of kapha dosha.
  • Mix (snigdha-ruksha): This is applied in conditions due to vitiation of both vata and kapha dosha.[Cha.Sa.Sutra Sthana 14/8]

Classification based on the intensity of heat

  • Mild (mridu): Mild fomentation is indicated on sensitive areas like testicles, precordium and eyes. This type of fomentation can be done in individuals with weak constitution or in mild diseases.
  • Moderate (madhyama): Moderate fomentation can be done on groins, in moderate intensity of disease and in persons with moderate strength.
  • Intense (mahat): Indicated in severe morbidities and if the person is strong. [Cha.Sa.Sutra Sthana 14/07]

Classification based on the application on body part

  • Local or on any single body part (ekanga): Indicated when a particular part is affected
  • Whole body(sarvanga): Indicated in generalized conditions [Cha.Sa.Sutra Sthana 14/66]

Classification based on the medium of fomentation

  • Heat bath/Radiant heat (tapa): This includes fomentation therapy in a chamber room (jentaka), fomentation using heat in a trench (karshu), fomentation in a chamber (kuti), fomentation in a pit (kupa), and fomentation using a heap of dung (holaka) types.
  • Vapours or steam (ushma): This includes bolus fomentation (sankara), lying on the medicinal mattress (prastara), fomentation by heated stone slab (ashmaghana), steam fomentation using a tube (nadi), fomentation using a pot (kumbhi), fomentation on heated floor (bhu) types.
  • Liquid medium (drava): This includes shower technique or affusion (parisheka) and tub fomentation (avagaha).
  • Bandage (upanaha)[Su.Sa.Chikitsa Sthana 32/3][3]

Classification based on the therapeutic purpose

  • For pacification (samshamana) of vitiated dosha
  • For purification (samshodhana) of vitiated dosha[Dalhana on Su.Sa.Chikitsa Sthana 32/22][3]

Properties of the drug which impart fomentation

The herbs used for fomentation therapy possess properties like hot potency, penetrating, motile, unctuous, rough, heavy and liquid.[Cha.Sa.Sutra Sthana 22/16]

General indications of fomentation therapy

  • Painful conditions: E.g.earache, headache, cervical pain, pain in foot, knee, thigh, calf, colicky pain etc.
  • In stiffness conditions: E.g.stiffness of muscles, joints, stiffness in flanks, lumbar and abdominal region
  • Diseases due to vata: E.g.hemiplegia, monoplegia, facial palsy, sciatica, subluxation of ankle etc.
  • General conditions: E.g.rhinitis, cough, hiccup, breathing difficulty, heaviness of the body
  • As a prerequisite to panchakarma procedures[Cha.Sa.Sutra Sthana 14/24]

Contraindications of fomentation therapy

  • Conditions with predominance of pitta dosha in basic body constitution (Prakriti) and disease.
  • Conditions like bleeding disorders, diarrhea, diabetes mellitus, rectal prolapse etc.
  • Those who regularly consume alcohol and astringents
  • During hunger, anger, depression
  • Pregnant ladies
  • Weak, extremely emaciated, immune-compromised and unconscious persons[Cha.Sa.Sutra Sthana 14/16-19]

General instructions during fomentation therapy

  • Exposure to direct wind shall be avoided during fomentation therapy.
  • If the fomentation is performed for purification treatments (shodhana), it must be done after proper internal and external oleation (snehana).
  • Fomentation should be done only after the complete digestion of meals.
  • After fomentation the person should take rest by covering the body with a blanket. Warm water shall be used for bath after fomentation treatment.

Assessment of effect of fomentation therapy

Features of optimal fomentation

The signs of optimal fomentation are relief from cold, pain, stiffness, heaviness; and disease pacification.[Cha.Sa.Sutra Sthana 14/12]

Features of inadequate fomentation

The features of inadequate fomentation include persistent feeling of heaviness, stiffness, pain, and associated complaints.

Features of excessive fomentation

Excess fomentation leads to vitiation of pitta dosha, unconsciousness, giddiness, excessive thirst, burning sensation, weakness of body, eruptions in the body parts, pain in joints, and increased body temperature. [Cha.Sa.Sutra Sthana 14/14] [A.H. Sutra Sthana 17/16]

Importance in the preservation of health and prevention

Fomentation therapy improves the process of digestion and metabolism [Su.Sa.Chikitsa Sthana 32/22][3] and removes obstruction. Administering fomentation, especially after oleation, controls vata and prevents clogging of feces, urine as well as semen.[Cha.Sa.Sutra Sthana 14/4] Good digestion and proper elimination of wastes are essential components of health. [Su.Sa.Sutra Sthana 15/41][3] Fomentation in a chamber room (jentaka) and exposure to sunlight (atapa) are indicated in season-specific regimen for the preservation of health in winter. [Cha.Sa.Sutra Sthana 6/14]

Importance in management of diseases

Fomentation therapy liquefies the dormant dosha adhered to the micro channels of body.[Cha.Sa.Siddhi Sthana 1/8] It relieves pain [Cha.Sa.Sutra Sthana 14/12], removes stiffness in joints and improves functioning. [Su.Sa.Chikitsa Sthana 32/22][3] Generally,fomentation therapy pacifies the diseases caused due to vata and kapha dosha. [Cha.Sa.Sutra Sthana 14/3]

In the diseases caused by the suppression of natural urges, swedana is indicated to relieve the obstruction of vata. It is an important treatment in the initial stage of fever [Cha.Sa.Chikitsa Sthana 3/142], accumulation of metabolic wastes (ama condition) [Cha.Sa.Vimana Sthana 2/13],piles (arsha) [Cha.Sa.Chikitsa Sthana 14/250] and hemiplegia (pakshaghata). [Cha.Sa.Chikitsa Sthana 28/100]

Dosha specific action of fomentation methods

  • Heat bath/Radiant heat (tapa) and vapors or steam (bashpa sweda): Mitigate kapha
  • Bandage (upanaha sweda) : Mitigates vata
  • Liquid medium (drava sweda): : Mitigates pitta dosha associated with kapha
  • Sweda without using fire (niragni sweda): Mitigates vata associated with kapha and adipose tissue (meda dhatu)[Su.Sa.Chikitsa Sthana 32/14-15][3]

Contemporary approach

In fomentation therapy (swedana), the body is exposed to varying intensities and qualities of heat which results in sweating. Nowadays different heating techniques are used as a therapeutic measure. This includes diathermy, infra-red, ultraviolet, ultrasound, wax bath, heat pads, hot water bags etc. Sauna bath is practiced in many parts of the world as a method for fomentation.

Physiology of sweating

Among the three main types of sweat glands, eccrine sweat glands are distributed over a much larger body surface area and they are mainly responsible for thermoregulation. These glands get stimulated by thermal heat and also by emotional stress. When the body is exposed to hot conditions or by exercises a redistribution of heat from the core to periphery happens through an increase in blood flow in the periphery (skin). This thermophysiological change stimulates the sweat gland. The increase in body temperature is sensed by central and skin thermoreceptors. The preoptic area of hypothalamus process this information and triggers the sudomotor response. Sympathetic cholinergic stimulation mediates thermal sweating. The release of acetylcholine from nonmyelinated class C sympathetic postganglionic fibers binds to muscarinic receptors on the sweat gland, stimulating sweat production. The clear cells present in the secretory coil of eccrine gland produce an isotonic fluid. It moves to the resorptive duct which traverses the dermis. The sodium and chloride ions get reabsorbed in this stage. The resultant hypotonic fluid is released on to the skin surface as sweat. Due to a decline in non-thermal feedback to the brain on termination of activity or hot conditions, sweat rate drops and the surface sweat gets evaporated quickly.[4] [5]

Effect of sweating on body fluid dynamics

Heat stress results in sweating. Sweating causes water loss which leads to a reduction in water volume and electrolyte content in the body. The osmolarity of body fluids increases due to sweating. Sweat is hypotonic in body fluid. In a study conducted on six healthy men, a reduction of 4.1% in body weight was reported when subjected to dehydration through thermal means (sauna) and through exercise. The extracellular fluid loss was found to be more after thermal heat stress when compared to exercise dehydration. Loss of sodium chloride was more during thermal dehydration while potassium loss was more through exercise.[6]

Another study conducted in 10 volunteers who exercised in the heat for 90-110 minutes reported decreased plasma volume by 9.4% compared with the pre-exposure value. The body is compensating for the reduction in central circulating blood volume, due to hypovolemia as a result of dehydration or due to dilation of peripheral vasculature, through the body’s ability to mobilize water from extravascular to intravascular space. During dehydration higher water loss is reported from extra cellular fluid space than from intracellular fluid. Sodium and Chlorine are the main electrolytes found to be excreted during thermal dehydration. These are the main electrolytes in extra cellular fluid.[7]

Therapeutic use

The main physiological function of sweating is thermoregulation. While sweating the heat is transferred from body to the water present on the skin's surface.[5]

Removal of toxins

Some studies report the chemicals, persistent organic pollutants, heavy metals, bisphenol A etc. in sweat. Their concentration is also reported to be higher in sweat than in blood or urine. This suggests the possible action of skin as an excretory organ for body toxins. Further studies are required to prove this activity of the skin.[5]

Skin health

The secretions from the sweat glands play an important role in maintaining the health of skin. Through the eccrine sweat water, natural moisturizing factors and antimicrobial peptides are delivered to the skin's surface. This might be helpful in maintaining the epidermal barrier homeostasis. In the treatment of atopic dermatitis and other dry skin conditions, the preservation of sweating might have a positive effect. Sweat glands also produce antimicrobial peptides such as dermcidin, lactoferrin etc. which are essential components of defense mechanism against skin infections.[5]

In type 2 diabetic patients, improved glucose balance was reported when subjected to hot water heat stress intervention. Hot water immersion induced therapy is also found to have beneficial effects in peripheral artery disease.[8]

Stem cell stimulation therapy: An increase in CD34-positive cells in circulation has been reported after repeated heat stress therapy.[9]

Cardiovascular diseases: In a cohort study it is reported that repeated heat stress therapy results in a reduction of cardiovascular risks.[9]

Current clinical practices

In current clinical practice, fomentation therapy is done through three different forms:

  1. Application of heated bolus (pottali)
  2. Application of vapour/steam
  3. Application of hot liquid

Fomentation using bolus

The medicines are made into a bolus form and are applied over the affected body part directly or after dipping in a suitable medium like oil, decoctions, milk etc.

The bolus of sand (valuka sweda)

Clean and fresh sand is used for fomentation. The sand is heated and made into a bolus by tying it inside a cloth. This bolus is further heated by placing it over a hot pan and is applied over the body parts. It is a dry form of fomentation. This is usually indicated in acute pain conditions associated with swelling where presence of accumulation of metabolic waste (ama) is suspected.

Bolus of herbal powders and paste (churna pinda sweda)

Medicated powders are used to induce sweating. The bolus can be used in dry form or along with oil as per the condition. It is indicated in disorders of osteoarthritis, stiffness of neck etc.

Bolus of citrus fruit (jambeera pinda sweda)

The bolus is prepared with citrus fruit, medicated powders and oil. This is indicated in conditions of joint pain, stiffness etc

Bolus of leaves of herbs (patra pinda sweda)

Leaves of medicinal plants are used for making the bolus. These leaves along with medicated powders and grated coconut, are cooked along with suitable medicated oil. The bolus is prepared out of this and applied over the body parts. It is indicated in diseases caused by vata dosha, hemiplegia, paraplegia etc.

Bolus of medicated rice (shashtikashali pinda sweda)

Medicinal pudding is prepared using a particular variety of rice grain along with milk and Sida cordifolia (Bala). Bolus is prepared out of this pudding. Before applying it over the body it should be again heated by dipping it in a mixture of hot milk and decoction. This is the most nourishing type of fomentation. It is indicated in muscle wasting, degenerative diseases, cerebral palsy etc.

Fomentation using vapour

Steam chamber (bashpa sweda)

Fomentation using a chamber room, in which the person either can sit or lie, associated with a steam source outside. Through this whole-body sudation is made possible. Usually this type of fomentation is used before purification therapies.

Steam through tube (nadi sweda)

The vapors coming from a steam source is redirected into the affected body parts using a hollow tube. This is indicated in conditions of painful joints like low backache, knee OA, etc.

Fomentation using liquid

Pouring method

Pouring fermented liquid (dhanyamladhara):Warm fermented liquid (dhanyamla), prepared from cereals is poured over the affected body parts to attain fomentation. Medicated buttermilk, decoctions, medicated milk and medicated oils can also be used as per the patient's condition.

Immersion method

The affected body parts are immersed in warm decoctions or oils

Mode of action of induced sweating

A raise in the external environment temperature leads to the vasodilation of cutaneous blood vessels. This increases the cutaneous microvascular blood flow. The systemic conductance is also increased. To maintain homeostasis, the cardiac output increases. As a result, the cardiovascular system gets stimulated, which in turn may stimulate the entire body metabolism. An improvement of endothelial function and reduction in arterial stiffness may also happen as a result of sweating. Sweating reduces the core body temperature. Anti-oxidant capacity might get also improved. It may also improve the lung's vital capacity and thereby aids in micro ventilation. The above data shows the action of induced sweating on different systems however, more studies are required to find out the exact mode of action.[9]

Current researches

Whole body fomentation therapy results in cardiovascular stress. There will be increase in cutaneous vascular conductance followed by increase in systemic conductance. But the homeostasis will be maintained by decreased conductance at noncutaneous bed and increased cardiac output. It might be due to this increased cardiac output and by the redistribution of blood from central to peripheral circulation, a reduction in central venous pressure occurs during the onset of passive heating. In certain studies, it is noted that passive heating significantly raises the left ventricular ejection fraction.[9] In an observational study on whole body steam fomentation (sarvangabashpa sweda), significant increase in pulse rate and blood pressure was recorded immediately after the completion of the therapy. This raised blood pressure and pulse rate were transient as it came back to normal after five minutes of therapy.[10]

Effect of fomentation through tube (nadi sweda)

Fomentation through a tube (nadi sweda) and simultaneous passive stretching have shown a beneficial effect in knee joint contractures due to rheumatoid arthritis.[11] Local hyperthermia improves blood circulation and local blood tissue metabolism. It also helps in reducing inflammation by lowering various inflammatory mediators. In a study on 50 patients of osteoarthritis (sandhigatavata) treated with Nirgundipatra pinda sweda for 21 days, it was effective in reducing the symptoms like pain and swelling in joints, stiffness and crepitus. Range of movements of effected joints improved.[12]

Fomentation with bolus of medicated rice (Shashtikashali pinda sweda) for 28 days in 8 children with cerebral palsy showed promising results in improving the motor system functions like muscle power, muscle tone, deep tendon reflexes etc. It also showed improvement in the quality of life.[13]

List of theses done

  1. Shakuntala Sundi (2008): Comparative study of Nirgundighanavati and Tindukamrita capsule with nirgundipatra pinda sweda in the management of Amavata. Department of Kayachikitsa, IPGT&RA Jamnagar
  2. Jayadip Kumar P Shah (2008): Effect of Tiktakshira basti and patrapinda sweda in the management of cervical spondylosis (Asthigatavata). Department of Panchakarma, IPGT&RA Jamnagar
  3. Apexa G Vyas (2011): A clinical study on Samvardhana Ghrita and Shashtikashali pinda sweda in the management of Cerebral palsy. Department of Kaumarabhritya, IPGT&RA Jamnagar
  4. Rahul Ghuse (2015) : A clinical study on Shashtikashali pinda sweda and Yoga basti in the management of cerebral palsy. Department of Kaumarabhritya, IPGT&RA Jamnagar
  5. Rani Sangeeta Ishwar Singh (2017): A randomized clinical trial on brihatyadi yapanabasti and patrapinda sweda with aadityapakaguggulu in the management of cervical spondylosis w.s.r to asthigatavata.Department of Panchakarma, IPGT&RA Jamnagar
  6. Purohit Palak Kishorbhai (2017): A comparative clinical study on Shashtikashali pinda sweda and Yoga basti in the management of cerebral palsy. Department of Kaumarabhritya, IPGT&RA Jamnagar

Related chapters

Sweda Adhyaya, Langhanabrimhaniya Adhyaya

Abbreviations

Cha. = Charak, Su. = Sushruta, A. = Ashtanga, S. = Sangraha, Hr. = Hridayam, Sa. = Samhita

List of References

The list of references for Swedana in Charak Samhita can be seen here

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References

  1. Monier-Williams, Monier-Williams Sanskrit- English Dictionary, 1st edition; Oxford University Press, Svedana, Page 1285
  2. VC Patil. Principles and practice of pancakarma. NewDelhi:Chaukhabha publications;2106.Chapter 9, Svedana Karma(Sudation therapy);p.193.
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 Sushruta. Sushruta Samhita. Edited by Jadavaji Trikamji Aacharya. 8th ed. Varanasi: Chaukhambha Orientalia;2005.
  4. Baker LB. Physiology of sweat gland function: The roles of sweating and sweat composition in human health. Temperature (Austin). 2019;6(3):211-259. Published 2019 Jul 17. doi:10.1080/23328940.2019.1632145
  5. 5.0 5.1 5.2 5.3 Gerrett N, Griggs K, Redortier B, Voelcker T, Kondo N, Havenith G. Sweat from gland to skin surface: production, transport, and skin absorption. J Appl Physiol (1985). 2018;125(2):459-469. doi:10.1152/japplphysiol.00872.2017
  6. KOZLOWSKI S, SALTIN B. EFFECT OF SWEAT LOSS ON BODY FLUIDS. J Appl Physiol. 1964;19:1119-1124. doi:10.1152/jappl.1964.19.6.1119
  7. Nose H, Mack GW, Shi XR, Nadel ER. Shift in body fluid compartments after dehydration in humans. J Appl Physiol (1985). 1988;65(1):318-324. doi:10.1152/jappl.1988.65.1.318
  8. Heinonen I, Laukkanen JA. Effects of heat and cold on health, with special reference to Finnish sauna bathing. Am J PhysiolRegulIntegr Comp Physiol. 2018;314(5):R629-R638. doi:10.1152/ajpregu.00115.2017
  9. 9.0 9.1 9.2 9.3 Crandall CG, Wilson TE, Marving J, et al. Effects of passive heating on central blood volume and ventricular dimensions in humans. J Physiol. 2008;586(1):293-301. doi:10.1113/jphysiol.2007.143057
  10. Sanjeev R, Francesco C.Hemodynamic effects of Sarvanga Swedana (Ayurvedic passive heat therapy): A pilot observational study.Ayu. 2013 Apr;34(2):154-9. doi: 10.4103/0974-8520.119669.
  11. Patel MM, Patel MV, Gupta SN, Patel KB. Effect of Nadisvedana with simultaneous passive stretching on correction of sandhijadya. J Ayurveda Integr Med. 2018;9(1):61‐63. doi:10.1016/j.jaim.2017.07.002
  12. Alpesh J, Charmi SM, Alankruta RD, VD Shukla. Clinical effect of Nirgundi Patra pinda sweda and AshwagandhadiGuggulu Yoga in the management of SandhigataVata (Osteoarthritis).Ayu. 2011 Apr;32(2):207-12. doi: 10.4103/0974-8520.92588.
  13. Apexa GV, VK Kori, S Rajagopala, Kalpana Sp. Etiopathological study on cerebral palsy and its management by ShashtikaShali Pinda Sweda and SamvardhanaGhrita.Ayu. 2013 Jan;34(1):56-62. doi: 10.4103/0974-8520.115450.