Originally Posted by Tom Cruise
It could be that, like a lot of things which increase your red blood cell count, it increases the viscosity of your blood. Which in turn can lead to heart problems and the like.
Im not an expert but at college (16-18 so high school age in America) we learnt that this happens when people blood dope, or use EPO, so it would figure that the same negative side affects would be present here. Though probably no where near as bad
It's a big problem with EPO alright, the blood thickens and the heart is placed under a lot of strain as a result. Several cyclists died in their sleep from their circulation slowing down to dangerous levels. Much greater risk of blood clots, strokes etc.
For years, a lot of tour cyclists used to set alarms for the middle of the night to interrupt their sleep and to kick-start their circulation with a half hour on the exercise bike.