This isn't a personal review of of cordy5, but it is personal.
My younger brother, who is 18, is a high school wrestler. Actually he's the captain of his wrestling team. He heard me talking about the endurance effect that the cordy 5 has had on my cardio, so he wanted to give it a try.
Mike has had some racing heart rate issues for some time -sudden movements or sustained extreme physical exertion will sometimes start his heart racing due to some extra nerves that get excited. He was going to get an ablation (zap the nerve) but the doctors couldn't induce it on the table so they did not do the procedure. This was years ago.
Anyway, he takes the cordy 5 sample and a little while later heads off to practice. They were doing partner carrys up stairs. Mike was doing well when he felt his heart begin to race. This wasn't unusual for him, and normally he would stop what he was doing and sit down and the racing would stop. For one reason or another he decided to keep going. When I asked him about it later he said that he didn't want to be left behind. While I was upset with him for jeapordizing himself, I do understand why he did what he did.
Anyway, his heart wouldn't stop racing for 45 minutes. He didn't feel well and was taken to the hospital. They did some tests on him and found a minor amount of heart damage.
Here is where it gets interesting. Cordy 5 has an ingrediant that is an analog of something that is given to patients with SVT, and is used during stress tests. Though Mike has since been cleared to continue wrestling, with a surgery scheduled for after wrestling season, the question arises, what would have happened if he hadn't had the cordy 5 in him? More damage for sure; oxygen starvation of cells was partially countered with the effects of cordy 5, minimizing the actual damage done.
So, at the end of the day he learned a lesson about what he can push and what he can't, and at least partially because of the cordy 5 the damage was very slight.
Good product, thank you Millennium.