Live data from Hacker News

Metabolic and cellular differences between sedentary and active individuals

howardluksmd.substack.com

101–110 of 159 posts

Re: Metabolic and cellular differences between sedentary and active individuals

#101
I will recommend working while walking. Also learning while working.

One needs a standing desk and a treadmill.

Also, if you are watching an episode of a tv show, randomly watching YouTube videos, listening to podcasts, etc., walk an hour or two during that time. That time won't feel 'wasted'.

I can't point you towards any study. But intake of new knowledge and information is somehow better while I am walking.

Re: Metabolic and cellular differences between sedentary and active individuals

#102
post #83

Earlier quoted context omitted.

Usually in this context it means “the max effort that you can sustain for 2 minutes”. Same thing goes for a 20-minute max effort or even an hour etc.

Max effort is kind of nebulous as it really means different things to different people. Heart rate is probably the simplest and universal gauge for this... Atm I am somewhat unfit (relative to my past/potential) so when I do a round on the pads in muay thai/boxing which could be 2-4 minutes, my heart rate sits around 180-185 for the duration of the round. Often, sparring is actually more relaxed than pads because the…

The meaning of the words “Max effort” doesn’t change or vary.

It’s just that some people have a max that is lower than others, or at some points in your life your effort is lower than at others, as dictated by physical, mental, or psychological capacity for that person at that moment.

For example a normally sedentary person might find it mentally and psychologically uncomfortable to exercise strenuously. That doesn’t mean they’re not putting forth max effort.

Max effort means max effort.

Re: Metabolic and cellular differences between sedentary and active individuals

#103

Earlier quoted context omitted.

> you'd still be left with 2 hours of personal time to do all your extracurriculars like cleaning, parenting, spousing, hobbying, shopping, repairing things, etc. In what way is parenting an extracurricular activity?

I took the comment as sarcasm.

whoooosh

I’ve been relying on Poe’s Law for so long I never thought it could happen to me.

Re: Metabolic and cellular differences between sedentary and active individuals

#104
One workaround that I have to maximize my steps is to have walking meetings whenever face 2 face camera is not mandatory or when discussing ideas. All hands - walk. Meet with peer - circle the office parking lot. The goal is to maximize steps starting from the first wake minute. That side I still have fatty liver. My doctor said it’s most likely due to genetics.

Re: Metabolic and cellular differences between sedentary and active individuals

#105

I haven't read the paper, but what I am curious about, how much of the damage can be turned back if someone becomes physically active after a long sedentary period? Let's say someone already had low fat oxidization and/or cardiovascular disease, how much of that can be "cured" by being active? This post claims: the good news is, this is reversible. But is that so? Is it also proven to reverse things in all cases? I w…

I didn’t strength train until my 40s. Started being able to curl 15 pound weights. Now at the same reps I’m up to 20 or 25. Years later :) It takes time. It’s a very steady climb. No doubt if I was a teenager I’d make much faster progress. But it’s not just about the raw amount of weights, my running pace, etc. The benefits for my mental health in the moment. Improving my sleep and stress. And myriad other benefits m…

"If you're in your 70s and benching 150, you fuckin' think anyone needs to help you with a fuckin' jug of milk? Fuck that."

- Dr. Mike Israetel, sport scientist and expert vulgarian

https://youtu.be/r8zcF6Ut7lo?t=903

I hope you continue, friend. The best age to start is when you're young, but the second best age to start is today. Keep at it, and never struggle to get out of a chair.

Re: Metabolic and cellular differences between sedentary and active individuals

#106

A lot of people in the comments are expressing curiosity about "ideal" amounts of exercise to avoid these sorts of problems. I have a real-life friend whose hobby is studying this stuff. His recommendations boil down to: - 1/week 20 minutes HIIT: 5 minutes warmup, 3x(2 minutes high intensity + 3 minutes low intensity) blocks. - 1/week strength training focused on large muscle groups. - 12,000 steps per day walking (H…

Isn't 12k steps like 6 miles? I could plausibly jog that much, but to walk it every day seems like a huge time commitment.

You can get 3k-4k steps easily just by moving a bit more during your day. The other 8k can be done in an hour walk. You can jog as well if you're short on time but it's probably nice to spend an hour outside every day anyways?

Re: Metabolic and cellular differences between sedentary and active individuals

#107
post #23
post #21

Earlier quoted context omitted.

tl;dr; Nope. Assuming that HIIT workouts are 100% vigorous activity (unlikely), then a "few" instances would only add up to around 24 minutes of vigorous activity, which is far short of the minimum recommended 75 minutes of vigorous activity. If you are short on time then performing HIIT for 15 minutes five days a week will get you much closer to the minimum requirements.

4-minute HIIT run (30s full/5s walk, repeat) makes you vomit and not feel your legs. 15 minutes of HIIT 5-times a week is a wishful thinking. It's not your typical "vigorous" activity. At my athletic very best I could at most chain 3 HIITs in a row and be destroyed for a few days.

Fair enough, I don't think it changes my the conclusion though.

On that basis, I would say that someone whose entire exercise regime is doing HIIT a few times a week for 8 minutes (24 minutes in total) is not going to be hitting the 6x multipler required for an equivalent of regular 150 minutes of exercise.

Re: Metabolic and cellular differences between sedentary and active individuals

#108

Between this and http://myticker.com (posted recently), I want to share a theory of mine: 1) the internet is mostly made up of spaces where the median opinion is vanishingly rare among actual humans. 2) the median internet opinion is that of a person who is deep into the topic they're writing about. The net result is that for most topics, you will feel moderate to severe anxiety about being "behind" about what you sh…

BMI isn't a great predictor of health. Waist-to-hip ratio and body-fat percentage are probably somewhat better indicators.

https://www.yalemedicine.org/news/why-you-shouldnt-rely-on-b...

Re: Metabolic and cellular differences between sedentary and active individuals

#109
post #17

Would 8 minute HIIT a few times a week do the job?

It's better than nothing. It's better than likely some multiple of that in lower effort activities. But you probably want to round it out a little bit.

It almost certainly will improve your VO2MAX.

Re: Metabolic and cellular differences between sedentary and active individuals

#110

A lot of people in the comments are expressing curiosity about "ideal" amounts of exercise to avoid these sorts of problems. I have a real-life friend whose hobby is studying this stuff. His recommendations boil down to: - 1/week 20 minutes HIIT: 5 minutes warmup, 3x(2 minutes high intensity + 3 minutes low intensity) blocks. - 1/week strength training focused on large muscle groups. - 12,000 steps per day walking (H…

Here is a study that tries to answer that question: https://link.springer.com/article/10.1007/s40279-024-02120-2

A good summary: https://bannister.coach/mitochondria-and-exercise-how-differ...

Quoting the conclusion:

> In this systematic review and meta-regression covering ~ 50 years of research data, we demonstrate that the magnitude of change in mitochondrial content, capillarization, and VO2 max to exercise training is largely determined by the initial fitness level. The ability to adapt to exercise training is maintained throughout life irrespective of sex and presence of disease. Larger training volumes (higher training frequency per week and larger number of training weeks) and higher training intensities (per hour of training, SIT > HIT > ET) are associated with greater increases in mitochondrial content and VO2 max. Therefore, training load (volume x intensity) is a robust predictor of changes in mitochondrial content and VO2 max. Increases in capillarization occur primarily in the early stages of exercise training (< 4 weeks) with ET, HIT, and SIT equally enhancing capillaries per fiber, while ET is more effective in increasing capillary density (capillaries per mm²) due to less pronounced muscle fiber hypertrophy.

Post reply on HN