the runner had extremely painful cramps through her body she described as more painful than breaking her arm, she lost all bodily functions, was vomiting for two days, I would say she was very lucky to have recovered, I've since spoken to her about more realistic fluid requirements for the marathon, she would have needed about a litre and a half of water provided it wasn't overly hot and even then another half a litre would have taken care of that a pinch of sea salt in a litre of water would have taken care of her salt needs. from sweat loss.
She was given the advice from non runners who thought they knew what they were talking about that she needed to drink plenty of water before the marathon, she started drinking copious amounts of water the night before the marathon, and in the morning before the marathon, she then proceeded to drink from every drink station until about two thirds or the way around she was unable to continue running , she was hospitalised for at least a day as a result, as you will be aware, it caused hyponatremia, diluted the salts in her body and flooded her cells with excess water causing loss of ability to maintain exercise or in the end even stand.
Gary Moller Comments:
What Wayne describes here is the condition that I like to call "soggy body syndrome". It has been the biggest killer of runners and multisports athletes over recent years. It is rare in front runners simply because they are working too hard to swallow liters of water, are sweating heavily and are not out on the course long enough to do too much damage. It is the people who are towards the back of the field who are most at risk.
Prevention is as simple as drinking only as much as you need to replace most of what is being lost during an event. This means listening to your body and responding to its thirst signals. The advice that you often hear from "experts" and the sports water companies that thirst sensations happen too late to prevent dehydration is mostly rubbish - sure that may be the case for people who have not yet learned to listen to their bodies properly. Good athletes are good listeners; they learn through training to listen and respond early, sensitively and appropriately to the many signals that their bodies are sending all the time, including thirst. Those athletes who are not yet at one with their bodies can get some outside feedback assistance with learning by using some scales to weigh themselves before and after training and competition. This way they can calculate their exact fluid needs. 1kg of weight loss from an exercise session equals 1 liter of water which means needing to drink about 1 liter of water during a similar workout in the furure; depending, as well, on temperature and humidity.
Drink too much and you will slow down: Drink far too much and you will probably die.
Winning marathoners train for the conditions they expect to encounter, often including being able to tolerate extreme dehydration.
Hyponatraemia is easily confused with heat stroke and heat exhaustion and the treatment for each are very different (More about these in a future posting). Mass participation events should have medical and first aid personnel who have been trained to recognise and manage these. What I will say in the meantime is this condition is difficult to treat and requires immediate expert medical attention. Do not take any chances by doing a wait and see - get medical help if there is any suggestions of hyponatraemia.