Answer: This group is vitally important to the scientific validity of the study. The mental health of this group is also monitored but they simply continue with whatever interventions they would have otherwise undertaken. Without this group, it is impossible to say whether any observed effects are directly due to the intervention or would have just happened anyway.

Answer: No, not unless you are told to by your doctor.

Answer: Inflammation results from the release of a number of different chemicals by the cells of the immune system. It is a normal, short-term healing response to tissue damage where it leads to swelling and redness; and to infection where it leads to fever and malaise.

However, if significant quantities of these chemicals are present over a long period of time – usually as a result of stress or autoimmune disease – it can have negative effects including depression, skin conditions such as eczema and psoriasis, thickening of the blood vessels which can result in high blood pressure and heart disease, arthritis and inflammatory bowel disease.

Answer: A study design that randomly assigns participants into the intervention group or a control group. As the study is conducted, the only expected difference between the control and experimental groups in a randomized controlled trial (RCT) is the outcome variable being studied.

Answer: Absolutely not. Just a towel and plenty of warm dry clothes. We do recommend that you use clothes with few or no buttons as they are easier and quicker to get off and on thereby minimising the time you spend exposed to the cold air at the start and end of your session in the water.