Classes and Exercise

Data
Finished week four of the course, about to begin week five- the last week of the course. I do love programming, and the course (U of T's Learn to Program: Crafting Quality Code) is set up cleverly. Rather than teaching lists (no, no pun) of commands and functions, there is a nice flow that allows more intuition. This week was classes, and something about it reminds me of games. Programming, as other language learning (and especially pure math), has this fun element of structure. In the total rigidity and definition there is an opportunity to bring forth your own personality. The clear boundaries suit me, and I find thinking of clever ways to program highly satisfying. I do wish there was more programming, though. I also hope to finish week five this week, and thus start the next course at the beginning of next week.

Physical
All that I love about math is the inverse of what I love about the human body. Or, to give a better example- I love to learn about the heart and the brain. The heart is amazing in its simplicity, and the brain in its complexity. The heart isn't necessarily simple, but it is rather straightforward. And the brain is a mess.
My first goal is trying to understand which exercise recommendation I should give to someone who could do anything. Or, simply put, what is "best". That sounded so simple, and yet is such a marvellous mess! The recommendation today is, officially:
150 minutes of moderate intensity aerobic or 75 minutes of high intensity aerobic
2 days of muscle strengthening
Flexibility
Balance
I wanted to find the original exercise recommendation, but finding the first is a challenge. As one article cites the preceding, which cites its predecessor (rather than all just quoting the first that said "30 minutes of moderate aerobic activity"), in a long train, I arbitrarily stopped in 1995, at R.R. Pate et al's Physical activity and public health: a recommendation from the Centers for Disease Control and Prevention and the American College of Sports Medicine. A challenge I always have is to not look up tangent points (such as the highly enticing "250,000 deaths are due to lack of physical activity"). Sticking to the main points- their goal was to identify which exercise to promote and how to promote it. 
This article was written, quite clearly, before resistance exercise began to compete for attention. 
The recommendation: 30 minutes of moderate physical activity (note- not exercise. Gardening counts), preferably daily. The reason for moderate physical activity- so that people will stick to it. Activity and not exercise- more of the same, and so even doing an activity in bouts of ten minutes will suffice. This brings up the basic question of- if someone can do high intensity- is it "better"? 
I realize that asking better brings me back to my aforementioned love of clean conclusions, which exercise is clearly not. The benefits from exercise are so widespread that one exercise recommendation can't be superior to another in every way. 
Isn't that a shame!
But new questions arise:
1. Original article that states that moderate is on par with high intensity.
2. I am so tempted to write "ten minute bouts" but that has recently been debunked.
3. How did they get to the dose? Why 30 minutes?
I also began another qrticle (or, really, book) from the same year, and hope to report more on it next time. My ambition had been two articles a week. For now, one will have to suffice.