Fitness Musings

Here is an example of oversimplification to the point that the video is probably more confusing than anything else.

This is a problematic clip, because it rolls a lot of assumptions into the statement. If one is doing a *maximal* isometric and sustaining it long enough for some motor unit "rotation" to occur and fibers to fatigue enough that it leads to recruitment of some of the motor units that are harder to get on board, then I think it is fair to say that isometrics can "recruit more fibers." But without those sorts of caveats, the video comes across as a broad "X is better than Y" statement that conveys very little useful knowledge or detail and is likely just to make people more opinionated as they form opinions based on limited information.

There are also relevant points to explore regarding velocity of the dynamic action you're comparing isometrics to, what the chosen isometric position might be, how many joints are involved, the current fatigue state, and more. There is also the issue of what "safer" means in this context, and that could be a whole conversation by itself.

Tl,dr: it depends on a lot, and these quick clips are not conducive to teaching people about the variables that these things depend on. Neuromuscular physiology is complicated.

They activate the most muscle fibers andthey're the safest because you're notmoving #mindpump

A funny observation:

Fit pro: constantly harps on "trusting the process" (and rightly so) when they want their clients to chill out and be patient about their results

Also fit pro: always wants learning to be instant so they can monetize or weaponize a new technique, insight, or process right away.

***

If you want to separate yourself from the rest of the industry, perhaps try to take a more mature approach to your learning and growth than most other people do. Physics is hard. The body is complex. Logic is often counterintuitive. Commit yourself to learning for the long haul, and try to avoid the urge to seek instant gratification. The implications of new concepts don't always reveal themselves right away, so stop expecting things to take a day, or a week, or a month.

If you're playing this right, it's a long game.

Whenever a person acts like they can know what specific exercises someone does just by looking at them, that tells me that they don't really understand exercise or the body very well.

Yes, that applies to seasoned trainers and everyone else who thinks their experience gives them absolute knowledge about things.