Hydrotherapy, Balneotherapy, Spa Therapy and Water Therapy: How the Terms Differ
Hydrotherapy, balneotherapy, spa therapy, aquatic therapy and water therapy overlap and are used loosely. Here is how research papers use each term, and why it matters when reading claims.
Content last updated . This page has not been medically reviewed.
Why the Words Matter
Water-based health practices are described with several overlapping words, and the same word can mean different things in a brochure, a clinic and a research paper. A 2010 proposal for worldwide definitions in this field names the lack of internationally accepted terms as one barrier, along with a trend to use balneotherapy mainly for wellness concepts. [1] Knowing the terms helps you read claims, search for research and tell medical care from a spa experience.The Terms in Plain Language
| Term | How sources use it | Notes |
|---|---|---|
| Hydrotherapy | Therapy using plain tap water, in the 2010 definitions proposal. [1] Rehabilitation papers also use it for exercise in water, for example after knee replacement. [2] | Used both narrowly (plain water) and broadly (any water-based practice). |
| Balneotherapy | Bathing in natural mineral or thermal waters, using mudpacks, or both, as a Cochrane review defines it. [3] The 2010 proposal adds natural gases and medical peloids. [1] | Often tied to health resorts and spa towns; see balneotherapy in Europe. |
| Spa therapy | Used as another name for balneotherapy: the Cochrane review title reads "Balneotherapy (or spa therapy)". [3] | The same word is also used for leisure businesses; ask what is being offered. |
| Aquatic therapy or aquatic exercise | Exercise or treatment in a pool; in a Canadian interview study it was used by physical therapists, assistants and a kinesiologist. [4] A Cochrane review used "aquatic exercise" for trials in knee and hip osteoarthritis. [5] | See aquatic physical therapy. |
| Climatotherapy | Therapy using climatic factors, in the 2010 proposal. [1] | Mentioned here only to explain terms. |
| Health resort medicine | Medical activities in health resorts "aiming at health promotion, prevention, therapy and rehabilitation", with balneotherapy, hydrotherapy and climatotherapy as core elements. [1] | Defined in the same proposal as a medical field. |
| Water therapy | Not defined in the sources we read. | A general, informal phrase. Ask what exactly is being offered. |
Terms That Are Often Mixed Together
Reviews sometimes group the terms. A 2023 mini-review examined hydrotherapy, balneotherapy and spa therapy together for blood pressure and concluded that many clinical trials are still needed. [6] A 2025 review of balneotherapy in rheumatology rated certainty about its effects as very low. [7] Grouping makes it hard to know which practice, water or setting produced a result, so this library names the specific practice wherever the source does.Other practices people connect with hydrotherapy have their own pages: saunas and steam rooms, Kneipp-style water treatments, hammam and Roman baths and Japanese onsen. Colon hydrotherapy ("colonics") is a different matter and is covered only as a claim check: colon hydrotherapy.
Using the Terms When You Search or Book
- Ask whether a service is led by a licensed clinician for a health condition, or is a leisure experience. See wellness hydrotherapy and clinical aquatic rehabilitation.
- Be careful when a title such as "hydrotherapist" or "water therapist" is used. Rules for these titles are not described in the sources we read, and they differ by place. See who is who.
- A "mineral" or "thermal" water claim is a balneotherapy claim, and the evidence for such claims is limited. See hydrotherapy, balneotherapy and spa therapy compared.
Evidence Labels
This page is about terminology, so there is no single evidence rating. For specific uses, balneotherapy for rheumatological conditions has very low certainty of benefit in a 2025 review. [7] Aquatic exercise in knee and hip osteoarthritis has moderate-quality evidence for small short-term effects in a Cochrane review. [5]Frequently asked questions
Is hydrotherapy the same as balneotherapy?
Not in the narrowest definition. One proposal uses hydrotherapy for plain tap water and balneotherapy for natural mineral waters, gases and peloids. [1] Many papers and businesses use the words loosely.
Is spa therapy a medical treatment?
It can be. Balneotherapy, also called spa therapy, is studied in trials for conditions such as rheumatoid arthritis. [3] A day at a leisure spa is not the same thing, and the evidence is limited. [7]
What is aquatic therapy?
Exercise or treatment in water, often in a warm pool, used in rehabilitation. A Cochrane review used the term "aquatic exercise" for trials in osteoarthritis. [5]
What are peloids?
The 2010 proposal lists medical peloids with medical mineral waters and natural gases as substances used in balneotherapy, and the Cochrane review describes mudpacks as one form of balneotherapy. [1][3] The sources we read do not define the word further, but it points to mud-type preparations.
Is "water therapy" a recognized medical term?
Not as a defined term in the sources we read. It is a general phrase, so ask what the service includes.
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Safety
References
- Gutenbrunner C et al. A proposal for a worldwide definition of health resort medicine, balneology, medical hydrology and climatology. International Journal of Biometeorology (2010). PubMed record. Read 2026-10-22.
- Alrashedi SN et al. The Role of Hydrotherapy in Enhancing Recovery After Knee Arthroplasty: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Healthcare (2026). PubMed record. Read 2026-10-22.
- Verhagen AP et al. Balneotherapy (or spa therapy) for rheumatoid arthritis. Cochrane Database of Systematic Reviews (2015). PubMed record. Read 2026-10-22.
- Marinho-Buzelli AR et al. The use of aquatic therapy among rehabilitation professionals for individuals with spinal cord injury or disorder. Journal of Spinal Cord Medicine (2019). PubMed record. Read 2026-10-22.
- Bartels EM et al. Aquatic exercise for the treatment of knee and hip osteoarthritis. Cochrane Database of Systematic Reviews (2016). PubMed record. Read 2026-10-22.
- Moini Jazani A et al. Effect of hydrotherapy, balneotherapy, and spa therapy on blood pressure: a mini-review. International Journal of Biometeorology (2023). PubMed record. Read 2026-10-22.
- Aribi I et al. Efficacy and safety of balneotherapy in rheumatology: a systematic review and meta-analysis. BMJ Open (2025). PubMed record. Read 2026-10-22.