I have read that article excerpt and it doesn't line up with my experience hiking over the years that unless I drink electrolytes after a hike I end up with major leg cramps a few hours later. I don't use the sports drinks but I do use Nuun. I have better experience with Nuun than I do with Doug's sport drink substitute. I have tired varying my water intake over the years and it has little or nothing to do with the post hike leg cramps so I attribute it to loss of electrolytes due to perspiration. Some of the symptoms of dehydration are headaches which I have heard attributed to lack of water.
I do remember a radio show on the Boston Marathon that the biggest issue they have to deal with is hyponatremia which I attributed to the body sweating out electrolytes and water and only taking in water to replace it without electrolytes.
I also remember all the scientific sounding hype that came out a couple of years ago about leg cramps and how they were not related to electrolytes and the authors were discovered to be trying to sell spicy liquid as an alternative
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