I started a fast yesterday. I’m not sure how long I will be doing this one, but one thing I’m going to really push for this time is doing exercise.

The last time I fasted, I went 14 days; and lost like 15 lbs. A decent chunk of that ended up being muscle - it took a bit for my muscle to return after the fast (and return it did, with increase). This time I’m going to try something different.

There is a YouTuber I watch occasionally - Siim Land. He is a pretty intense Estonian guy (who has excellent English), and he does a lot of biohacking videos. Very much into intermittent fasting, nutrition, exercise; applying a scientific mindset.

He suggests that while you are fasting, that you should do resistance training. Cardio is also good for stimulating growth hormone, lymph, oxygen, and blood flow, but resistance training has additional factors that do awesome things like prevent muscle loss and assist in autophagy, plus releasing even more growth hormone than cardio.

The cell generally operates through a what are called anabolic and catabolic processes (determined by the source of the nutrients) which is regulated by a kinase called mTOR. When you start to restrict the inputs into the system, it deregulates synthesis of new cell parts and, under extreme conditions like fasting, causes autophagy. Literally means “self-eating”.

So, while fasting encourages this cell destroying behavior, it’s not all bad. It goes after deregulated cells first - those that aren’t operating properly; like cancer cells, or old cells, or cells with broken organelles. They get starved out, and broken down for parts. Then, because the human body likes to maintain about the same number of cells through its entire existence, it does one of two things - causes new cells through mitosis (cell splitting), which means a neighbor cell divides or genesis (release of stem cells), which means that a stem cell travels to the location and differentiates.

Ok, so that sounds pretty good for your health, to regenerate your cells. It is pretty good, which is why calorie restriction and fasting are shown to be really important for longevity. On the flipside of that, is I don’t want my muscle to go. This is where the exercise comes in. When you do resistance training it has a protective effect on certain types of muscle (but not all types of muscle).

I’m not sure how long I am going to fast this time, or how much exercising is going to increase the difficulty of the fast, but I’m going to give it a shot and see. Day 2, I ran a mile (with my best time yet of 9:25 min/mi) and lifted weights. So far so good.

If I stop posting, then it means it didn’t work. Whoops.