It's actually sort of ridiculous to only base one's ideas of Aboriginal foods on the records of the fur traders and explorers when those peoples are still around and still have traditional knowledge intact around their cultural foodways. A lot of work has been done by members of those communities to document their own histories, which have tended to be displaced in the North American cultural narrative by the stories told about them by outsider explorers and traders (which are not always wrong but are also not insider stories of a people).
There's an ongoing tendency in paleo/primal communities to neglect the abundance of information out there from actual Indigenous peoples on their own foodways, and I think we make a huge mistake in doing so because there's a lot to be learned by looking at the real dietary practices of the people we claim to want to emulate, and mythologizing them as people of some misty past misses a lot of opportunity for learning.
“If I didn't define myself for myself, I would be crunched into other people's fantasies for me and eaten alive.” --Audre Lorde
The interplay of exercise and ketosis
I don't know of any large studies done to this effect, rather haven't looked very hard for them, but Peter Attai's N=1 is an interesting post.
This study is positive proof that it royally sucks to be a lab rat. This study still doesn't change the fact that ultra low carb diets are not the best choice for endurance athletes and rat studies make a piss poor basis to make dietary changes for anything other than the poor rats that volunteer for the next pointless lab experiment.
But there have been human lab rats as well. The decades and decades of children raised on a ketogenic diet to control epilepsy are examples. They have competed in school athletics and grown up just fine with no adverse effects on their health. Of course, once they hit puberty, they have been allowed to drop ketosis in favor of pizza and soda but, by then, a great many of them were completely cured.
F 5 ft 3. HW: 196 lbs. Primal SW (May 2011): 182 lbs (42% BF)... W June '12: 160 lbs (29% BF) (UK size 12, US size 8). GW: ~24% BF - have ditched the scales til I fit into a pair of UK size 10 bootcut jeans. Currently aligning towards 'The Perfect Health Diet' having swapped some fat for potatoes.
The studies on adult epileptics have not been going on for as many decades so there is not such a huge body of evidence yet but the exact same thing is happening so far in the studies done at Johns Hopkins.