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Not to mention the fact that good sleep hygiene provides immediate payoffs as well. The single best thing I have done for my health was giving myself the gift of a regular sleep schedule and sticking to it. I perform better in every aspect of my life. Even if I feel like I have less time than I did before, I feel much better every day than I did when I was getting < 7 hours of sleep every day.

Interestingly, I feel I have more time that I did before, mostly because I'm mentally alert and more productive for more hours.

I couldn't agree more. I work a lot and long hours, but I almost always insist on getting 7 hours of sleep a day.

I am curious, what is consider good sleep hygiene academic wise.

In a nutshell setting aside 8 hours, going to sleep and waking at the same time even on weekends and holidays, refrain from stimulants and depressants 8 hours before bed.

Recommended reading: Why We Sleep

> From what I gather, aerobic exercise...

That was my impression as well after doing some research in this area a while back. Although I looked specifically at longevity and cardiovascular studies there was a peak benefit at about 2hrs per week after which virtually no more benefits were observed.

2 hrs a week of intensive aerobic exercise sounds like an easy to remember target if that's what research shows.

What constitutes "intensive"?

I finally got a heart monitor. So far, I get into "zone 4" for a few minutes every day. Zone 5? Not so much...

Personally, I define vigorous exercise when I hit 95% of my maximum heart rate (220-age) non-stop for 30 minutes. 100% is doable but a bit too extreme. I think I've seen similar definitions in health literature.

Worth noting that the various "max heart rate formulas" are just guidelines. Plenty of people routinely hit above their predicted rate, and plenty of people cannot get there.

Yeah, the "based on age" makes it tough. I would love for there to be something more prescriptive. That said, I suspect just trying already puts me in a decent position.

I am pretty sure that is very extreme and 70-80% of MHR is fine to consider "vigorous", especially for someone who is untrained.

Mayo clinic says 70-85% of your max heart rate [1] counts as "vigorous". Not sure what the zones on your monitor are set at.

[1]: https://www.mayoclinic.org/healthy-lifestyle/fitness/in-dept...

That would mean heart rate around 126 to 153 for me, evidently. Which, actually sounds low. Which I guess is good for me? :)

I was using "zones" per the Strava app lingo. I rarely make zone 5, which would be 174+ heart rate. I spend a fair bit of time in the 160 range, though.

If you're just using a formula your heart rate zones could be quite far out.

For example, 220-age suggests my maximum HR is 178 and my threshold HR (85% of this) is 151, but in fact my max HR (determined empirically) is 188 and my threshold HR (based on an actual threshold test) is 162.

How do you do a threshold test? Do you need a doctor?

For cycling, I do a long warmup then ride as hard as I can (uninterrupted) for 30 minutes and take the average HR for the last 20 of the 30 minutes. There are online calculators you can plug this value into to give you the 5 zones.*

I do a test every 3 months, as the zones can shift as you get fitter.

Running might use a different protocol, but the same principle applies.

* These days I base my training on a 3-zone system: low intensity, below aerobic threshold; medium intensity, between aerobic and anaerobic (lactate) threshold, and high intensity, above lactate threshold. This is the system preferred by researchers, as it's based on real physiological markers.

Translating the 3 zone system into the 5 zone: low intensity equates to zones 1-2, medium is zone 3 and zone 4 up to your (lactate) threshold value, and high intensity is everything above this, i.e. the top part of zone 4 and all of zone 5.

So 'vigorous' per the Mayo Clinic would be medium intensity on the 3 zone system.

Thanks! I'll have to consider doing a test like you describe downthread sometime. Most of my biking is just getting home from work. And, well, that is only 20 minutes on the bike. Large hill, but still just 20 minutes.

The canonical running test is to run an all out 5K. You can then derive pretty simple training paces based on tables. See: Daniels Running Formula. Or any number of training calculators on the Internet. A 5K is a very good measure if your overall running fitness and a pretty good predictor of race performance from 10k to Marathon. It helps you set up good training paces. Then it just comes down to volume. When you find your HR creeping out of zone don't be ashamed to walk to chill it out.

I primarily do cycling to commute. That said, I've signed up for a 5k this Dec. Will make sure to wear my heart monitor and see how I do.

You can definitely go out too hard in a 5K, it isn't a 400, 800, or 1600M effort, but if you aren't hurting and questioning your life choices the last mile you weren't going hard enough :)

That Mayo Clinic page has another way to calculate target HR.

Target HR = RestingHR + (MaxHR - RestingHR) x 0.85

So, if your RestingHR = 70 :

Target HR = 70 + (178 - 70) x 0.85 = 162

Mine's even more out... I'm a full 20 bpm higher than that formula would suggest. Mid-30s and still do over 200 bpm at the end of a 5K.

As an ultra runner I can tell you 130-150 is "vigorous" in medical literature. Actually for anyone over 30, maintaining 150+ is probably threshold and providing you different kinds of adaptation. Ideally you spend 80% of your training time in Z3. You use Z4 to train VO2 max and Lactate Threshold. VO2 max is not very trainable. Lactate Threshold is. Z5, once you are "trained" and can run in Z3 for extended periods of time (30+ minutes) is almost purely for speed work and learning to run faster. It helps develop coordination and push through barriers. It is mostly anaerobic, so some amount of intervals in Z5 is good. Z4 is longer tempo work and fast/hard intervals.

Marathons are meant to be run at the edge of Z3 so you avoid hitting your lactate threshold. Think of your ability to run in each zone as separate gas tanks. Your Z5 gas tank is very small. Your Z4 gas tank can be trained, but is still relatively small. Your Z3 gas tank is basically unlimited (ultra marathon pace, 50+ non stop miles possible for almost any healthy human). Cardio is not about suffering.

Most people should be fast walking to maintain Z3 rather than suffer it out in Z4 and Z5 when they are getting started.

Is it the same for biking as running? My hunch is I was silly and looking at distance when I thought I could get more out of cycling. That is, I know I can bike 30+ miles with fairly little effort. Running 2 miles near kills me. (Granted, some of that is hernia related. Fixing that, but not expecting it to be easy any time soon.)

Checking my last long bike ride, I see I maintained 120 heart rate for majority of it. Which means I spent most of the time in zone 2, and makes sense that would be easy to maintain. (Contrasted with my last commute, where I cover 270 ft of elevation in about 7 minutes, mostly at about 160 heart rate...)

A few years back when I was looking at Tour de France stats, IIRC a lot (most?) of those guys spend all day around 120 bpm too. The difference is that they are putting out pretty much twice the power that I do for that same effort.

And probably you too, given I have a hill around the same size on my commute that takes me around 7 minutes too.

https://www.strava.com/segments/622627 is the hill I'm talking about. Agreed that they are likely putting in much more power than I can at that heart rate.

My naive understanding is that I can push more time in higher heart rates and slowly pull up what I can do in the lower ones. That said, I'm just aiming to be consistently in the 6 minute time frame for that hill by next year. As things are, I'm quite winded if I hit the low 7 minute time frame. So, trying to pay attention to any methods I could use to make that better.

Yep, just a little steeper than mine: https://www.strava.com/segments/623328

AFAIK your 'naive' understanding is pretty right on. I subscribe to the philosophy of spending as much time as possible in the "sweet spot" (search on that term), which is toned down just a bit from the best effort you can do in an hour.

Yep. Cycling has some different terminology, but the basics of zone training are the same. How much time per zone, intervals, training cycles, it all works the same in terms of adaptation.

I wouldn't stop at two hours just because there's no additional benefit that manifested in a study on some super-specific outcome.

You probably care about other benefits as well.

Sure. But there are also risks associated with exercise; you want to minimize those too.

Weight training tends to be moderately cardiovascular. Not an out-and-out replacement for cardio, but your heart will be pumping hard at higher weights/reps. Same thing for a long session in a hot sauna. Just throwing some nearly-as-good alternatives out there for people who hate treadmills.

I hate treadmills, but going for a bike ride or a walk is awesome. I don't know why people go to the gym to run...

Sometimes the weather blows.

Probably for the same reason people go to the gym to exercise yet don't do any pushups at home: we pathologically avoid exercise, so we often must compartmentalize it away from our life to actually do it.

You can watch TV on a treadmill, something that is much harder (and more dangerous) while running outside.

Because it’s easy to set targets and measure them while in the gym, but it’s not easy to fit that kind of exercise into the day to day.

People often live too close to work for the bike ride to really be considered exercise, or too far, where they couldn’t feasibly fit it into their day.

I get it, doing exercise for free seems like a no-brainier, but not everyone’s life and exercise needs converge neatly to make it easy.

> easy to set targets and measure them while in the gym

The cost of the gym will pay for a GPS watch and heart-rate monitor pretty quickly.

But I understand that some places might be too high density or unsafe to run, or the weather is too hostile.

I'm fortunate enough to live 10km from work, so I switch up between running AND riding the distance.

There's another article on the front page that pollution increases the risk of either getting or accelerating Alzheimers, I forget which. Either way, if you live in a city, getting aerobic exercise out of doors is probably counter-productive when done for the purpose of cleaning your brain. In that case, indoors at a gym might be an option, if it's well ventilated and fresh air is filtered first.own.

Because the outside air is polluted and having to wear a air filter while exercising is unpleasant.

Because I have to watch out for traffic and pedestrians outside, and driving to a cycling/running path takes about 15 minutes anyway.

Because looking at healthy, fit people exercising gives me more motivation to get in shape.

Because I can devote more attention to my audiobooks than if I was exercising on the streets.

Because the gym is in my apartment complex, so I just go downstairs and walk 2 minutes to the gym.

In particular, dead lifts wind me every time. After a set I feel like I just ran up a few flights of stairs. Other lifts not as much, but man I have respect for the dead lift. Works damn near every muscle in your body at the same time.

Yeah, it's not aerobic at all, unless you're doing 1 set of 100,000.

Gotta be more careful with your words. There's some component of aerobic metabolism in weightlifting, even if we colloquially think of lifting as anaerobic exercise. If you start breathing harder when you lift stuff, it's because your body needs more oxygen to provide energy to your body.

Technically you're correct (the best kind of correct!) but I don't know if I'd be under the opinion that somehow doing a 5x5 (or, whatever) of Deadlifts is going to positively effect your cardiovascular system in a training sense, to the point where doing separate cardio is unnecessary.

Depending on the exertion you put forth, a different energy system is going to be utilized by the body.

* Deadlifts: ATP Creatine Phosphate

* Cardio: Aerobic

I suggest you read Tactical Barbell and TB 2 the conditioning guide(search for PDF). Contrary to popular wisdom, the two systems are not independent of each other

No, I didn't say they were. The point being is that you're not going to get great aerobic conditioning from deadlifts when compared to any other specific aerobic activity, like running.

That shouldn't even pass the sniff test, yes? If you would like to test the theory, I'll run for 5 weeks, you deadlift, then we'll test our aerobic thresholds (or whatever else you'd like to do!) :)

Just to throw in some new terms, weight training tends to be more anaerobic, where things like distance running are more aerobic (where oxygen provides most of the energy). It's not an either/or, but more of a scale progressing from aerobic to anaerobic. Lifting more weight is generally more anaerobic than lifting less weight. And the downside of anaerobic exercise is that you can generally only do it for short periods of time.

Since I don't have a Science subscription, I can only read the summary, and they do not explain what type of exercise they required the mice do. So if someone with access can clarify, please do. But from what I know of similar "cleaning out" studies, the exercise is generally distance running. So weightlifting for a short period of time is probably not going to give you the benefit this study refers to, even if you're burning the same number (or more) calories, because you didn't do it for as long of a period of time.

"This is the mechanism by which the body cleans up most tissues. Except for the brain. The brain has a separate mechanism whereby lymphatic fluid (aka interstitial fluid) gets flushed out, taking wastes with it, only during sleep."

I've been thinking about this myself and I theorize that this all comes back, full circle, to your heart.

That is, both bodily and brain lymphatic fluid flushing mechanisms are driven by circulation - and the more efficient and powerful your blood circulation is, the more efficient and cleansing your lymphatic flushing will be.

And thus, your brains lymphatic flushing, while not directly driven by exercise, still benefits greatly from exercise due to the improvement in total circulation.

I think circulatory health and blood health are hugely important, for a lot of things, for a long list of reasons. I also think total load on the system matters.

If your system has a backlog of built up wastes generally, that backlog is going to be a barrier to efficiency in any particular system.

Note long ago someone listed some papers about the relationship between exercise and circadian rhythm : https://www.reddit.com/r/workout/comments/9n6f6p/the_greates...

it might be related to your comment too

Bio 101 after 2015 got an update. Researchers found out about lymphatic vessels in the brain:

https://www.nih.gov/news-events/nih-research-matters/lymphat...

> aerobic exercise is likely to do more good from the perspective of powering the lymphatic system than weight lifting.

This is conjecture? I do hope its true though! A frequent debate I have with a friend is whether weight-lifting or running has better effects. He claims 1 hour of weight-lifting raises your metabolism by many multiples vs more aerobic exercise. Its always a bit hard to have these debates though since we are mostly armed with anecdotes and not facts.

I suspect the answer is always moderation - somewhere in between.

I'm fairly certain it's true.

But that knowledge comes from 17+ years of firsthand experience (aka "anecdata") and reading (where I may not be able to cite my source anymore because I read it eons ago for personal reasons, not to try to win an internet debate). So I qualified it in hopes of keeping people off my back about citations etc.

So if you need citations for some reason, you will need to find them on your own. You might start with googling info about the benefits of walking and sources on how the lymphatic system works.

This is something very new to me, thank you!

One question- what is it specifically about sleep? Have we figured that out yet? And when you say "only", you mean "only" or you mean 99.9% of time?

Thank you for explaining this - I learned something today!

Hear that Elon?