The CDC (center for disease control) says that each year 100,000 people under the age of 30 die during or right after vigorous exercise. It's roughly 300,000 over the age of 30 that fall over dead. This totals 400,000 that they say die, during or soon after exercise. This huge and rather unbelievable if you've not heard this before. I'm convinced from all that I've heard and read that the crux of the matter at hand are minerals, or the lack of them. When you exercise you are sweating out more than sodium! You are sweating out everything your bones are comprized of. The average life span of a professional athelete is around 62 to 65. The average couch potatoe lives until around 70 to 75.
Try to get 60 minerals, 16 vitamins, 12 amino acids, and 3 EFA's, each and every day to prevent illness and promote longevity and healthfulness. If you sweat more than others, you'll need extra supplements.
For cardiomyopathy, bone up on SELENIUM...it is crucial. Make sure you minerals, when in a solid form, are chelated (AAC...amino acid chelate). Farmers have known this for a long time. They have no health insurance on their live stock and they put salt blocks out for them, or they will chew on the fence posts and the barns...it's called cribbing. In humans it's called pica. These are nutritional, deficency disorders. Humans don't chew on fence post (not socially acceptable). We instead eat salty snack foods, filled with empty, needless calories.
I'm rambling on here. Take your selenium for sure!