- Sickle cell disease
- The NHS advises people with sickle cell disease to avoid getting into very cold water, because a sudden change in temperature can trigger a crisis. If you have it, do not plunge unless Dr. Rockhead has agreed.
- The heart and blood pressure
- With a heart condition, high blood pressure or a raised risk of stroke, the check with Dr. Rockhead comes before any plunge, and he may say no. That includes blood pressure treated with tablets. With heart disease that is not under control, do not plunge. Harvard Health says a cold plunge is not advisable for anyone who has had cardiovascular disease, and that anyone with a heart rhythm problem, such as atrial fibrillation, should avoid it. The Royal Life Saving Society UK says the sudden rise in blood pressure can be fatal for someone with a heart condition.
- We advise against it
- With Raynaud's or poor circulation in the arms or legs, and with hives or asthma that cold brings on. In pregnancy and soon after surgery, only if Dr. Rockhead agrees.
- Tell Dr. Rockhead first
- Diabetes, nerve damage or numbness in your hands or feet, cold agglutinin disease, and every medicine you take. He may advise against the plunge, or ask you to see your own doctor first.
- The risks
- The shock when you get in: a gasp, fast breathing, and a jump in heart rate and blood pressure. Cold water also raises the risk of an abnormal heart rhythm and, possibly, of the heart stopping. Numbness can make it hard to climb out. Too long in the water can bring a dangerous drop in body temperature, and may cause frostbite or damage to the skin.