Like ECA is that dangerous compared to the other stuff, but this is an interesting tidbit that I thought I should pass on...

I'll bet that the football players that died from heat stroke were using (abusing) ECA or another stimulant/thermogenic aid. Ephedrine and similar stimulants allow you to exceed your 'natural' limit and detract from your body's natural overheating defense mechanisms.

This is a concern in the extremely hot weather the country is experiencing. If you are doing cardio outside in the heat and using ECA or a similar stim to give yourself a little 'pep' and burn a little adipose tissue be warned-

1) Stimulants like ECA increase your natural BMR (~3%?-I think clen is more, but not sure) and of course body temp

2) Increased body temp means hydration is key but often neglected by athletes

3) In very humid weather sweat will not evaporate off your skin thereby taking away your body's natural cooling mechanism

4) During cardio body temp normally rises so combined with stims in hot weather body temp goes up more

5) Body fat is an insulator-If you have a lot of it, your body will have a harder time cooling off. I am sub 10% and can really suffer in the heat and I sweat like a pig!

6) Ephedrine and other stims effectively take away your lactate threshold. You can reach much higher BPMs than normal during cardio. Increased workload means higher body temp and greater hydration needs.

All of these factors can lead to heat stroke if your aren't careful. As your body's temp rises and it cannot dissipate this heat by normal means the body begins to shutdown. Over temps of 104 you are in deep shit and if the temp keeps going up you will experience progressive organ failure and from that point on it is more or less irreversible ie death!

I used to take ephedrine all the time before my cardio workouts. Usually I got a huge boost one day and the next day I feel pretty flat. I would do long cardio as well (1-2 hours, gotta stay lean and mean). My buddy who is a triathlete uses it sometimes for his races. He said it raises your lactate threshold (almost removes it) and basically takes the 'rev limiter' off your engine (heart). Usually you'll be fried the next day as you pushed yourself over your limit. It also tends to really dehydrate you.

Pushing yourself beyond your limit will severly affect your ability to recover and have a solid workout the next day. In my opinion this alone is bad because big guys who don't do enough cardio can stress their hearts if they push themselves to hard (the more mass you have the more blood your heart has to pump to keep that tissue alive). Naturally big dudes (general body size not necessarily muscle example Shaq-he's not ripped just huge) have big cardiovascular systems and their hearts have adapted to pumping that much blood (as well their hearts and lungs are proportionally larger). When you 'artificially' increase body mass with gear your heart falls behind. Cardio strengthens the heart. I think this is why they say gear can lead to heart problems. Big guys need big engines. Cardio makes big engines (or at least conditions it to deal with increased demands). As far as I know there is no magic AAS that increases heart size and conditions it to pump faster and with greater stroke volume.

Okay I'm straying off track...

In conclusion:
ECA and similar thermo aids are effective fat loss aids, but be very careful using them before cardio. I very hot, humid weather they can you can defeat your body's natural protective measures. It is very tempting to go workout in the heat to sweat off the water weight and help accelerate your BMR. IF you are in the heat of the day doing cardio avoid stims and drink drink drink. If you have a good program going work out in the morning or evening or in the gym (if it is climate controlled). We all want to be super lean so just be safe.