Les bienfaits de la thalassothérapie


By definition, Thalassotherapy is the use of sea water and all the elements of the marine environment (seaweed, mud, sand, air, marine climate, etc.) for therapeutic purposes. It is always practised in a seaside environment in a specialized centre with medical monitoring.

Like blood plasma, seawater contains up to 92 minerals and trace elements that are beneficial to our health. Our body has the capacity to absorb all of these natural elements because its mineral structure is very similar to the structure of seawater: this is called the remineralization of the body.

During thalassotherapy treatments seawater is warmed to just above 32°C, which enables minerals to pass through the epidermis, reach the bloodstream and then the various organs. This process takes between 10 and 15 minutes.

Seawater : rich in trace elements

trace elements

Trace elements are necessary for the proper functioning of the human body. Their role is to strengthen the immune system for physiological balance.

For this, they bind to and activate enzymes. Enzymes are proteins responsible for biochemical reactions in the body. If there is a decrease in trace elements, enzyme activity also decreases, which can affect the body’s equilibrium.

Trace elements play a key role in the body’s immune defence. They act in several ways :

  • As enzyme activators of the immune system
  • As hormone activators which facilitates the activation and/or multiplication of immune cells (e.g: zinc activates thymulin)
  • By combating free radicals in oxygen. These are molecules naturally produced during cellular respiration which, in high doses, become toxic to cells. This is why they are also called antioxidants.

In Greek, “oligo” means “few”. Trace elements are minerals present in tiny amounts in our body. However, they have an essential function: “They act as catalysts, a bit like the spark that starts the engine of a car”, explains biochemist Isabelle Hininger-Favier.

Trace elements help the body’s reactions which are necessary to defending itself against viruses, stress or fatigue.

When in contact with trace elements, the tired body naturally recharges itself. It feeds on negative ions and mineral salts. It takes an average of 12 minutes in water for negative ions to pass through the skin and diffuse throughout the body. Potassium ions travel to the muscles, while calcium ions strengthen the bones. A simple swim in the sea therefore contributes to the purification of the whole body.

The well-being of the body

Les bénéfices de la thalassothérapie

In Thalasso treatments, the entire marine environment is put to use towards the well-being of the whole body. In particular, the sea air which is also rich in trace elements and helps dilate the blood vessels and accelerates exchanges between the human body and the environment. As in contact with water, the body relaxes and recharges itself with energy.

Seawater is also recommended for people with respiratory problems. Marine “aerosols” diffuse seawater droplets that have a decongestant effect on the airways. Sea air is rich in negatively charged ions, which are powerful antioxidants that improve lung function. Inhalation reinforces the immunity and health of every cell in the body. Studies have shown that inhaling salt air improves lung function in people with cystic fibrosis.


At the Thermes Marins de Saint-Malo, we are convinced that Thalassotherapy provides real benefits for the body and mind. We associate a multidisciplinary health team with high-performance equipment in order to offer the most effective treatment protocols. We worked in collaboration with a team of researchers from the Biomedical Research Institute of the Army (IRBA). Result: an unprecedented study to scientifically establish the benefits of Thermes Marins Thalassotherapy treatments on the body and the mind.

Les bienfaits des soins de Thalassothérapie

The Thermes Marins de Saint-Malo / IRBA study demonstrates the benefits of thalassotherapy treatments.

From the outset, the objective of this study was twofold: on the one hand, to prove the effectiveness of Thalassotherapy treatments and the immersion in warm seawater on sleep and, on the other hand, on the state of health and general well-being.

Equipment & Method

  • Study carried out in situ at the Thermes Marins de Saint-Malo
  • 11 voluntary participants aged 24 to 63
  • 3 experiments :
    • after 15 days of intense professional activity leading to moderate lack of sleep
    • during a 4-night stay at the Grand Hôtel des Thermes and 3 days with 12 Thalassotherapy treatments following the 7 specific Thermes Marins de Saint-Malo protocols
    • after the stay 
  • 6 parameters evaluated
  • Materials : EEG monitoring, saliva samples, tests: KSS, Pichot, EVA, HAD, PVT-B, POMS
  • Laboratory conditions

7 treatment protocols by Thermes Marins de Saint-Malo at the heart of the study

Study volunteers underwent Thalassotherapy and warm seawater immersion treatments at the Thermes Marins de Saint-Malo. These treatments are available in all the stays offered at Thermes Marins de Saint Malo.

Soin de thalassothérapie

Affusion Massage

Full body massage with oils performed by a hydrotherapist under a fine rain of warm seawater. The exceptional properties of the seawater which is drawn off the coast next to the establishment, filtered and heated, combined with the benefits of oils (orange, lemon balm and marjoram) and a unique massage protocol lasting 25 minutes developed at the Thermes Marins de Saint-Malo allow deep muscle relaxation and well-being.

Soin de thalassothérapie

The Algae Wrap

This is one of the flagship treatments of Thalassotherapy. Its relaxing and detoxifying effect is increased tenfold by the unique richness of the exclusive seaweed cream used at the Thermes Marins de Saint-Malo. It is indeed the most concentrated on the market. The wrap is followed by a draining rinse with warm seawater.

Soin de thalassothérapie

The Underwater Shower

This powerful underwater hydromassage of the whole body is performed by a hydrotherapist in a bathtub filled with seawater, using a precise and exclusive protocol, for deep drainage and relaxation.

soin de thalassothérapie

Dynamic Affusions

In this treatment by Thermes Marins de Saint-Malo, the body is massaged by several curtains of warm seawater shower heads that constantly criss-cross. Sedative and deeply relaxing, this unique protocol is effective due to the establishment’s affusion ramp: exclusive and patented, the ramp’s shower heads cross randomly and continuously, massaging a large area of the body and in particular all the “motor coordination” parts of the body for in-depth relaxation.

Soin de thalassothérapie

The Shower Bath

This relaxing multisensory treatment combines the mechanical action of a whirlpool bath and multiple shower heads, the benefits of seawater and light therapy. The result: deep relaxation of both body and mind.

soin de thalassothérapie

The Swimming Pool with Neck and Back Shower heads

Performed in a specialized seawater pool, this series of exercises performed in front of an underwater shower head located on the neck or back regions deeply relaxes muscles and tones the body.

Soin de thalassothérapie


A relaxation session launched by the Thermes Marins de Saint-Malo in a specialized heated seawater swimming pool. A specifically trained physiotherapist instructs and accompanies the client who uses floats for in-depth aquatic relaxation.

Results of the Thermes Marins de Saint-Malo / IRBA study

The benefits of thalassotherapy 1

For the first time, a rigorous scientific study has shown that a Thalassotherapy stay at the Thermes Marins de Saint-Malo brings concrete and significant benefits to health and physical and mental well-being. All tested parameters improved from +13 to +106%.

6 parameters evaluated, 6 significant results :

    • +31% on well-being
    • -55% on pain
    • +88% on relaxation.
  • SLEEP :
    • +20% total sleep time on the 1st night
    • +27% sleep time after 3 days of treatments
    • +51% of N2 sleep (recuperation) on the 1st night
    • +23% of N3 sleep (repairing) after 3 days of treatments.
    • -31% on the HAD scale.
    • -25% on the KSS sleep scale
    • -70% on the Pichot fatigue scale
    • -97% on the POMS mood scale.
    • -49% in errors on the PVT-B test.
    • +106% improvement in body suppleness
    • +13% in the vertical jump.

The results are immediate and last a week after returning to work.

Scientific results validate the perception of spa guests at the Thermes Marins de Saint-Malo.

Independently of this medical and scientific study, nearly 500 people who participated in a Thalassotherapy stay at the establishment commented on the benefits of their treatment. Their opinions all converge with the study carried out by the IRBA – EA 7330 Université Paris Descartes: Thalassotherapy in Saint-Malo eliminates tension and fatigue in order to recharge the body.

  • 98% are satisfied with the benefits of care
  • 92% feel in better shape after their stay

Source : satisfaction survey conducted from April 16 to September 8, 2017 among 475 people at D+7 and D+15 after a Thalassotherapy stay at Thermes Marins of Saint-Malo.

An important step for most clients, who can no longer anticipate a year without a Thalasso break at the Thermes Marins de Saint-Malo.

The exceptional Thermes Marins de Saint-Malo is the source of these results.

Our strength, which explains why the results of these two studies (scientific and customer satisfaction) are positive, undoubtedly lies in these 3 key points :

Exclusive protocols

All our treatments are the result of in-depth work carried out by our team of professionals. The team work to find the perfect gesture, the exact amplitude of the movement, the ideal succession of treatment phases and its optimal duration, the experts at the Thermes Marins de Saint-Malo combine all their expertise whilst actively listening to clients. Result: exclusive and completely successful protocols which increase the benefits of Thalassotherapy tenfold.

State-of-the-art infrastructures

To provide the best treatments, the Thermes Marins de Saint-Malo are committed to providing you with the best infrastructure. We design, create and manufacture the most efficient affusion ramps or heat wrap tables on the market and use an exclusive highly concentrated seaweed cream. These technical innovations, patented by the establishment, undoubtedly contribute to the excellent treatments provided there.

Trained and loyal professionals

Nothing is possible without people. Professional, rigorous and attentive, the Thermes Marins teams work every day for your well-being. Technical expertise is combined with a fine perception of mood and feelings for a result that is both optimal and tailor-made.

The exceptional loyalty of the staff, their ongoing training within the establishment, but also their attachment to the Thermes Marins de Saint-Malo are at the origin of this performance. Benefiting from state-of-the-art professional monitoring, the 3 doctors, the nutritionist, 10 physiotherapists, 50 hydrotherapists, 10 sports educators and 45 beauticians form a united team, motivated and driven by a desire for excellence.

Jean-Michel COLLEU
Thalassotherapy Director

Jean-Michel Colleu

We are proud of the work we accomplish.

Working with IRBA scientists was a great privilege, both technically and on a personal level, we all enjoyed our in-depth discussions. For the entire team, the results of this study truly recognizes the efforts made daily to ensure that the Thermes Marins de Saint-Malo strive for excellence. These results mean we will continue to strive to always give our very best to design and provide the most effective treatments.