Prescription Water Activities: Discover the Healing Powers of the Sea

Marseille (Bouches-du-Rhône), report

« Slowly but surely, step into the water. Look at those who are more accustomed: even if it’s chilly, let the water at least reach your waist. » At Roucas Blanc beach in Marseille, about ten women are gearing up to take the plunge. This water walking group is special: it’s a health sport class organized by the association Refaire Surface.

Most of them are there following a doctor’s prescription, like Valérie, 58 years old. For two months now, she has been walking in the sea four times a week. Her doctor directed her to the association due to obesity-related issues. For this fisherman’s daughter, the water has always been her element, though it had been a long while since she last swam in the sea.

« I didn’t do sports, apart from Tai Chi. I was afraid to face being overweight and not having a swimsuit that fits. Now, just seeing the sea when I arrive makes me feel calm. I’ve also gained endurance. Now, I want to come back to the beach with my granddaughter. »

She leads the group through various exercises that have them crossing the water. Butt kicks, elbow-knee touches, walking crawl… « Help, I’m drowning! », « I’m floating! » they laugh heartily. Illness is not a topic of discussion; all are there to unwind. As in many health care or prevention programs, the majority of participants are women.

In the water, Aurélien Guillois or Malie Rousier take turns leading the session. Both are sports coaches specialized in subaquatic activities. Aware that they primarily serve a privileged demographic—especially when it comes to diving—and recognizing the benefits of practicing in the open sea, they decided to adapt these activities for health sports.

There’s no pressure to perform; the practice is gentle and suits individuals’ fitness levels. Since 2024, they have been welcoming people with chronic conditions (ALD): metabolic diseases, obesity, diabetes, cardiovascular issues, heart failure… Doctors refer their patients to the association by first prescribing water walking, and perhaps later, snorkeling or adapted diving.

« This gradual progression in activities, above and below water, allows one to discover the biodiversity and natural ecosystem in a different way, to become aware of nature and its fragility, says Aurélien. The more you know it, the more you respect it. And a healthy nature makes healthy humans. »

« Watch out for the rocks!  Remember, that one is the cormorant rock; it comes there to dry its wings. » Malie enriches her classes with scientific explanations. « I call this rock that because it allows me to introduce an endemic species. It’s one of the few bird species that dives, and we often see them on the breakwater. »

She shares her knowledge about Posidonia, wave formation, and invites the participants to contemplate the marine environment or the Marseilleveyre range in silence. Nature is at the heart of the practice, and its effects on the body are just as important as those from physical exertion.

Lucie Cattaneo, a social health psychologist at the Marseille University Hospitals (APHM), is involved in the international research project Recetas, which assesses how nature can improve the physical, mental, and social health of urban dwellers. « We realize that people have a better quality of sleep, slightly less anxiety and depressive thoughts. Overall, people have better self-esteem and more confidence in the group. »

Other studies have already shown that twenty minutes of contact with nature is enough to lower cortisol levels, or that proximity to the sea has a direct beneficial effect on mental health.

At Refaire Surface, these effects are observed weekly. Some individuals arrive with a difficult relationship with their body shaped by their medical history or life traumas. In the sea, they cry tears of joy, not knowing they could feel so temporarily light. In the water, joint constraints are almost non-existent, the heart rate slows, and stress decreases. Paquerette, a retiree, braves the elements every week since late January. « It’s extraordinary. I’ve done years of aqua aerobics in a pool, but this is completely different. Every time, it’s a little adventure. »

Some reduce their medication after several sessions, cope better with their conditions, or accelerate their recovery. Even though Aurélien reminds them: « This remains a complement to the traditional care pathway, a non-pharmaceutical intervention. » Lucie Cattaneo explains that nature also plays a role in social relationships.

At each nature-based activity organized for the Recetas project, questionnaires are administered at the end of the session to gauge participants’ perceived dose of nature. Biostatisticians then analyze these interviews. These discussions prove that nature plays a crucial role: « It soothes these people, it helps break down social barriers related to different social status, ages, etc., and allows people to show themselves as they are, to create more authentic connections. »

Among the participants of Refaire Surface, many are retirees, sometimes very isolated. This is the case for Pascale, who joined after the death of her husband from a neurodegenerative disease. At the end of the session, Malie proposes the ‘supportive otter’ exercise: one person floats while the other holds their shoulders. It’s the first time in the morning they put their heads underwater, and only if they feel confident. Valérie supports Pascale, who lets herself close her eyes… « Oh ! It’s been a long time since I had a hug… Let’s see who can stay like this the longest? »

Anne-Marie, who is at her first session, comes back to land and feels the gravity again. She came for joint issues and overweight problems. She comes out « extremely relaxed to be outdoors… The environment is beautiful, and what an atmosphere!  Truly, it was a delight. » She is handed a steaming herbal tea and joins the group discussing on the sand. The Mediterranean Sea and the Calanques massif in the background, nature as their gym.