I just watched a very interesting Ted talk by Christopher McDougall, author of "Born to Run". Here's the link to the video. (I've also read the book which is very interesting) His whole thing is about barefoot running, but the setup is what I found interesting.
His position is that our brains developed very quickly about 2 million years ago because of a concentrated calorie source, i.e. meat. The only problem is that bladed tools only started showing up about 200,000 years ago, so how did we hunt? He says that the physical advantage that humans have to all the other animals is that we can sweat which gives us endurance. We are not suited to stalk our prey and kill them with our bare hands. His theory is that humans hunted as a pack and literally ran their prey to death.
This theory seems to make sense to me on the surface. What are other theories about this and what (if any) implications does this have on the current thoughts on "chronic cardio"?
I know there have been some studies relating long distance running to heart disease, but I'm assuming those were done on people eating a SAD diet. Is it different for people eating real food?
Edit: I just read an abstract on this from the University of Arizona. Here is the link.
Endurance running is generally thought to be beneficial for gaining access to meat in hot environments, where hominins could have used pursuit hunting to run prey taxa into hyperthermia. We hypothesize that ER performance may have been reduced in Neandertals because they lived in cold climates.