Warning signs.
Swimming can be a dangerous sport and cold water adds another level of danger so this isn’t purposefully a scary read but there are things that can sometimes catch us unaware in the outdoor swimming world so here are some that I have come across in my experience.
This list isn’t exhaustive or written by a medical expert so please take the time yourself to research and find out about conditions and remedies.
Everything we do has a level of risk and danger - the key to keeping safe is knowledge and mitigating that risk through safe practice. It’s never wrong to say that today isn’t your day and decide not to swim - the water will always be there, make sure that you are too !
Hypothermia is probably considered to be the biggest risk in winter swimming.
Getting cold is part of winter swimming - getting hypothermia is not.
It's very useful to know ( or at least have a rough idea ) of the water temperature so you know what you're getting into and can prepare for how your body may react. A very rough rule of thumb if you're new to cold water swimming is no more than 1 minute in the water for every degree of temperature. Take into account the weather conditions as well - 10 degrees of a calm sunny day is very different to 10 degrees if it's wet and windy.
One of the first symptoms of hypothermia is that you lose your ability to think straight and may cease to be aware of how your brain is interpreting your physical state. By that I mean that you may think you’re fine - but you’re not.
To check your level of coldness you can use the finger thumb technique - touch each finger with the thumb of the same hand.
Claw hand - you’re fingers will claw towards the palm as tendons contract with the old/
Numb hands and feet are common but you need to do a mental body check to make sure you are just ‘skin cold’ and not ‘core cold’. Core cold will contribute to hypothermia through the afterdrop process.
It’s a good idea to have someone who knows you and your swimming style spot you from a safe place where they can arrange assistance if needs be.
Signs for a spotter to look out for are -
Deterioration in stroke rate - if your stroke rate falls by 10% that could be an indication that you’re in trouble. E.g. if you usually stroke at 50 arm turns a minute and that falls to 45 a minute.
Deterioration of power - if your stroke rate is the same but you’re slowing down a lot e.g. Stroke rate is still 50 per minute but 100 metres now takes 3 minutes instead of 2 and a half.
Deterioration of stroke - e.g. if you have a high arm movement usually but that turns into being swoopy.
Confusion - you may nit be able to easily remember simple things or answer simple question like ‘who is the prime minister’ ‘when’s your birthday’.
Cardiac events
Are far more common than you think.
Immersing yourself in cold water creates stress on the heart and can also cause issues with blood pressure which in turn puts strain on the heart.
This usually manifests soon after getting in as the cold water shock hits you and an increase in heart rate and blood pressure is common before it settles. However if you have a condition ( whether you know about it or not ) which can be exacerbated by this you need to be very aware and listen to what your body is telling you. Cold water shockn can be lessened by repeated exposure but too much too soon can cause issues.
Never jump or dive into cold water - gradual immersion gives your body a chance to adapt.
Cold Water Shock
When you get into cold water the gasp reflex can happen and you can involuntarily breathe in water.
Never jump or dive in - gradual immersion gives your breathing time to adapt.
Transient Global Amnesia
If you get very cold you may experience a loss of memory.
SIPE - Swimming Induced Pulmonary Edema
A build up of fluid in the lungs - may be evidenced by wheezing, coughing or painful chest. As the lungs are comprised keep the patient sitting to help keep the lungs clear.
Blood Pressure highs and lows
Immersion in water automatically causes blood pressure to change. You are immersed in an environment putting pressure on your body - when you stand up that pressure is released and blood pressure changes may occur causing dizziness.
Uticaria
A reaction to cold water causing itchiness or hives.
Links
https://www.nhs.uk/conditions/hypothermia/
Afterdrop - Prof Mike Tipton explaining "Afterdrop"
Cold Water Shock https://rnli.org/safety/know-the-risks/cold-water-shock
Transient Global Amnesia https://www.scottishdailyexpress.co.uk/lifestyle/health/dr-michael-mosley-warns-little-27898893
SIPE - https://www.220triathlon.com/training/injuries/swimming-induced-pulmonary-edema-what-it-is-and-what-to-do-if-it-occurs/
Blood Pressure
https://www.health.harvard.edu/heart-health/is-swimming-in-cold-water-okay-for-my-heart
Cold Water Uticaria - http://dictionary.sensagent.com/Cold%20urticaria/en-en/
Good advice from -
Dr Heather Massey https://straightlineswimming.com/knowledge-base/the-best-advice-for-all-outdoor-swimmers-youll-ever-hear/
Dr Mike Tipton
https://www.youtube.com/watch?v=1axP_prHezY
I hope that hasn’t put you off - the purpose is simply to make you aware. It’s a bit like crossing the road - you always look left and right to check for danger but that doesn’t stop you getting across - awareness and knowledge mitigates the risks.Stay safe
Pauline Barker ( MamaBear )