I didn't say that cold shock was hypothermia, hence the ' & ' between the two words.
the links I've been reading must be wrong then (about the risks of cold shock response for accidental water falls, sudden aspiration of water, hyperventilation, blood pressure rise and the risk of cardio vascular difficulties etc)
Maybe, instead I should view the risks in this case as more akin to the habituated user who routinely uses the local lake in winter for wild swimming....
I apologise I misunderstood your comment. You’re not wrong about the hazard. It’s a possibility. The risk is very low though. The warning is more akin to the warning that an accidental electric shock from a domestic appliance can kill. In the vast majority of cases it’s not fatal. But A very small amount of current accross the heart can induce fatal arythmia ( that’s why RCDs were introduced ).
The cold dip into a harbour I mentioned was used for many years without issue, on a wide range of people. They had generally passed a medical, which later had an ECG.
Cold shock is real, it hurts. The chances of inducing cardiac arythmia, fatal vascular complications , involuntary aspiration etc. are very low in a healthy individual.
Leg cramp in swimmers can kill too, but it rarely does.
My own first experience of sudden cold water immersion was not as an acclimatised swimmer but as a 16 year old in the middle of a tidal lake.
Unpleasant, Intercostal muscles spasm too it’s hard to breath etc. but if you’re a confident swimmer you will generally make it out alive