I appreciate the studies that go back and forth on this topic (hey, that's science) but I can't help but think of our ancestors.
Readily available caloric intake, in terms of human evolution, is relatively new. I imagine our ancestors waking up in the morning and going out on a hunt or foraging for something to eat.
Personally, I've been doing intermittent fasting (16/8) for roughly seven years. I (typically) eat between 12 - 8pm and sleep between midnight-ish and 8 am. I eat a half cup of oatmeal at noon, a protein shake and some kind of fruit at roughly 3-4pm, and (usually) do some weight training roughly an hour later, followed by another protein shake after and a more broadly nutritious dinner (vegetable heavy, often with a lean protein and little to no carbohydrates) somewhere between 7-8pm. On days with this schedule my first activity after waking is spirited running/leaping up and down a flight of stairs for a total of 10 round trips. Speaking of which...
When I do cardio it's in the morning fasted. I don't have any science to back it up but for me, personally, something happens doing cardio fasted. It's "hard" but the response from my body and mind is amazing. I can't help but think my pre-agriculture caveman brain feeds off of some kind of reward in eating after running a 5k. I (typically) do this once or twice a week and the mental clarity and general "feeling" of health afterwards is amazing. At this point a more typical (at least for Americans) diet of eating a heavy breakfast, snacking on whatever throughout the day, and eating shortly before bed seems like it would ruin me.
I agree with how incredible I feel about doing some morning cardio while fasted. Surprisingly, I feel much less hungry until my eating window opens up at noon when I do morning cardio than on days when I miss it.
Anecdotes are what they are but I'm happy to hear I'm not alone in experiencing this phenomena. From what I understand humans have evolved to run incredibly long distances relatively efficiently because much of our densest caloric intake (historically) came as a result of simply chasing down our prey until it essentially collapsed from exhaustion.
Even though I live in modern times my practice of running what is a relatively long distance (5k) before eating seems to be an incredible "hack" compared to more typical, modern patterns of diet and exercise.
Curious on your take here - whenever I am very hungry I notice that my sense are acutely aware of any smell and are generally sharper (outside of the hunger part). Wouldn't that similarity translate to after a post fasted run that your brain is also much more acutely aware since it has been starved of food and is now trying to (in a historical sense) forage or hunt for food on a short term need?
I just commented elsewhere but to repeat myself with what I think you might be describing:
From what I understand humans have evolved to run incredibly long distances relatively efficiently because much of our densest caloric intake (historically) came as a result of simply chasing down our prey until it essentially collapsed from exhaustion.
Even though I find that it "feels" more difficult running for my calories (at this distance) I actually end up with surprisingly good performance. I can't help but think there's some fundamental drive and resulting reward system that (subconsciously) thinks "If you don't beat the animal you're chasing you're not eating today".
I imagine something similar happens in terms of your enhanced senses for smell, being similar for foraging (and potentially even prey detection).
> Curious on your take here - whenever I am very hungry I notice that my sense are acutely aware of any smell and are generally sharper (outside of the hunger part). Wouldn't that similarity translate to after a post fasted run that your brain is also much more acutely aware since it has been starved of food and is now trying to (in a historical sense) forage or hunt for food on a short term need?
This seems to be normal and common when fasting. It happens to me personally and I’ve read comments from other people who experience it too.
In terms of something comprehensive, no. I hope I made this clear with qualifiers such as "I imagine", "I don't have any science to back it up", saying it was all anecdotal, etc.
I've been practicing and developing my personal exercise and nutrition for well over 20 years. I've been around long enough to remember low-fat wars (fat is bad - just crank up the sugar!), cardio is best for weight loss (not at all), carbs are good, carbs are bad, high protein is good, now it isn't, now it's back, etc, etc. Like I said I appreciate the evolving science but developing a routine based on the latest "we studied 20 people and..." doesn't make much sense to me. Do I have it nailed? Am I a high performance athlete? No. What I do have going for me at this point is the fact that every indicator puts me in a high percentile for just about any physical and overall health metric. So I guess I have to be doing something right, right?
This is why I started with "studies that go back and forth". After the first two or three reversals from various studies and predominant thinking I realized I should just develop whatever works for me.
My high-protein diet and strength-training focused exercise program works for me. I essentially stumbled upon running while fasted because of my intermittent fasting schedule (which I love) on a few occasions where my life schedule didn't allow for exercise before the end of my fasting window. I more-or-less just started to wonder "Why is running long distances with no caloric intake in > 12 hours so exhilarating?"
I'm also generally aware that humans have been capable of feats such as running > 25 miles at a five minute pace (or less) well before modern equipment, training, and nutrition.
There have to be reasons for all of this, hence my theory.
Readily available caloric intake, in terms of human evolution, is relatively new. I imagine our ancestors waking up in the morning and going out on a hunt or foraging for something to eat.
Personally, I've been doing intermittent fasting (16/8) for roughly seven years. I (typically) eat between 12 - 8pm and sleep between midnight-ish and 8 am. I eat a half cup of oatmeal at noon, a protein shake and some kind of fruit at roughly 3-4pm, and (usually) do some weight training roughly an hour later, followed by another protein shake after and a more broadly nutritious dinner (vegetable heavy, often with a lean protein and little to no carbohydrates) somewhere between 7-8pm. On days with this schedule my first activity after waking is spirited running/leaping up and down a flight of stairs for a total of 10 round trips. Speaking of which...
When I do cardio it's in the morning fasted. I don't have any science to back it up but for me, personally, something happens doing cardio fasted. It's "hard" but the response from my body and mind is amazing. I can't help but think my pre-agriculture caveman brain feeds off of some kind of reward in eating after running a 5k. I (typically) do this once or twice a week and the mental clarity and general "feeling" of health afterwards is amazing. At this point a more typical (at least for Americans) diet of eating a heavy breakfast, snacking on whatever throughout the day, and eating shortly before bed seems like it would ruin me.