Live data from Hacker News

Cardio fitness is a strong, consistent predictor of morbidity and mortality

bjsm.bmj.com

311–320 of 556 posts

Re: Cardio fitness is a strong, consistent predictor of morbidity and mortality

#311

Some of my peers are deep into running. I don’t get it. Running is sometimes fun for me but most often painful. Then I overheard one of them (the fittest) say to a budding runner that he [should] do mostly easy sessions. Okay what’s easy to him? He said that so slow that it can feel awkward and unnatural. What? Then I searched around and found out about Zone 2 and how you should do most of your work in that zone when…

I love running and doing it consistently over ~10 years, always longing to get out again.

I'm the only one among my friends that do this, and I find this to be highly correlated with my running style: Really comfortable pace 7-10km through local forests, only (I tend to do more 10km more than 7km as I like it so much).

I learned this one time when I ran on a threadmill and realized the enormous difference between a slight variation in speed (from 11 to 9 km/h in my case, but the exact numbers don't matter), where I realized with this slight change I could go on indefinitely instead of being quickly exhausted.

Re: Cardio fitness is a strong, consistent predictor of morbidity and mortality

#312
post #305
post #268

Earlier quoted context omitted.

Neither is public healthcare system but if a free helmet for everyone reduces healthcare costs globally, ultimately it’s other people paying less. (I guess it doesn’t work if you don’t have public healthcare)

Saying other things that aren't free doesn't make the first thing become free. People who don't use helmets don't do it because they are too expensive. They do it because it's not convenient to carry, because it's not cool, because it messes your hair, because you need somewhere to store it. (Not) Free helmets solve zero of these problems, it's just a bad idea.

You are just nitpicking on semantics. If the total cost of publicly funded healthcare is reduced from people using helmets then that could result in not increasing what you are "making other people pay" even though you are also offering helmets at no cost. That is what most people would consider free.

People who don't use helmets for whatever reason would be more inclined to do so if they could just go pick one up, and didn't have to pay for them in a store. Even if those reasons are not that they are expensive. It's a great idea.

Re: Cardio fitness is a strong, consistent predictor of morbidity and mortality

#313

Some of my peers are deep into running. I don’t get it. Running is sometimes fun for me but most often painful. Then I overheard one of them (the fittest) say to a budding runner that he [should] do mostly easy sessions. Okay what’s easy to him? He said that so slow that it can feel awkward and unnatural. What? Then I searched around and found out about Zone 2 and how you should do most of your work in that zone when…

This is absolutely true, when I started, I didn’t have a zone2 while running and running is just suffering.

But gradually I could hold a lower heart rate while running and now my zone 2 runs are actually faster than my fastest pace I could hold a year ago. Now I enjoy running more than cycling (though my fitness are still probably mostly derived by cycling).

Re: Cardio fitness is a strong, consistent predictor of morbidity and mortality

#314

Some of my peers are deep into running. I don’t get it. Running is sometimes fun for me but most often painful. Then I overheard one of them (the fittest) say to a budding runner that he [should] do mostly easy sessions. Okay what’s easy to him? He said that so slow that it can feel awkward and unnatural. What? Then I searched around and found out about Zone 2 and how you should do most of your work in that zone when…

This has been the biggest game changer for me. People often think they need to push it hard and they quickly fatigue, burn out and hate going running. The trick is to do a 80% of your running sessions in zone 2 and 20% in high intensity to increase VO2 max. If you are at the start that means sometimes walking on hills and that is ok. There is a great book about this: https://www.amazon.com/80-20-Running-Stronger-Training/dp/04...

Re: Cardio fitness is a strong, consistent predictor of morbidity and mortality

#315

Weird that people seem to assert that causality is not established? There are hundreds to thousands of studies that show that pretty much all markers for mortality and morbidity go down with excercise, i.e. put someone regulalrly on a treadmill for a couple of month and pretty much all health markers improve. People implying that the study shows only correlation really don't seem to understand how we establish causal…

> People implying that the study shows only correlation really don't seem to understand how we establish causality in science.

Or perhaps you don’t fully understand the challenges of establishing causality? Just because an intervention causes an improvement in some bio markers that are associated with lower mortality (unfortunately) does not mean that the intervention will cause lower mortality.

The classic example is vitamin D supplements: Higher vitamin D levels are associated with lower mortality in many medical conditions. Vitamin D supplements increase vitamin D levels. But vitamin D supplements seldom lower mortality.

Why? Probably because vitamin D is produced in the skin when we are in the sun. The more healthy subpopulation of any study will typically spend more time outside, so they will have higher vitamin D levels. But it’s (relative) health that causes higher vitamin D, not the other way around.

The only way to reliably establish causality is really an end-to-end randomized controlled trial (RCT). Stitching together two RCTs is not sufficient.

(Not saying that exercise does not lower mortality BTW, just that it’s complicated, and a study such as this is probably picking up two signals: one causal and one purely correlational.)

Re: Cardio fitness is a strong, consistent predictor of morbidity and mortality

#316

Weird that people seem to assert that causality is not established? There are hundreds to thousands of studies that show that pretty much all markers for mortality and morbidity go down with excercise, i.e. put someone regulalrly on a treadmill for a couple of month and pretty much all health markers improve. People implying that the study shows only correlation really don't seem to understand how we establish causal…

No sorry but this is not how causality works. When event B happens a thousand times after event A, you cannot conclude that A causes B. For example, there could be a confounder, that is, a third event that triggers A and then B (so not A triggers B, but this third event triggers B). See The Book of Why by Pearl for more information on causality.

Can you give an example where causality is established then?

It sounds like I can hit you a 1,000 times, you feel pain a 1,000 times and you still don't believe there's a causality.

Re: Cardio fitness is a strong, consistent predictor of morbidity and mortality

#317

Some of my peers are deep into running. I don’t get it. Running is sometimes fun for me but most often painful. Then I overheard one of them (the fittest) say to a budding runner that he [should] do mostly easy sessions. Okay what’s easy to him? He said that so slow that it can feel awkward and unnatural. What? Then I searched around and found out about Zone 2 and how you should do most of your work in that zone when…

Yes, most of experienced runners' running is at a conversational pace, often literally (this is why running groups are popular).

To explain why harder isn't better: improvement in running comes only a little from muscular strength, so that mental model is bad.

Improvement is primarily based on aerobic development of the cardiovascular system. This is your body's ability to burn mostly-fat with oxygen, deliver the energy (ATP molecules) to muscles, and remove waste products. So you develop more capillaries, your heart gets literally stronger, and this fat-burning pathway gets more efficient.

Going too hard pushes into the anaerobic zone (burning sugar without oxygen). This is good training in some ways, but it can be counterproductive to aerobic development and, most important, it's too hard to do very much volume so the amount of stimulus is limited. By keeping it easy, you can do a higher volume of purely aerobic stimulus.

Re: Cardio fitness is a strong, consistent predictor of morbidity and mortality

#318

Some of my peers are deep into running. I don’t get it. Running is sometimes fun for me but most often painful. Then I overheard one of them (the fittest) say to a budding runner that he [should] do mostly easy sessions. Okay what’s easy to him? He said that so slow that it can feel awkward and unnatural. What? Then I searched around and found out about Zone 2 and how you should do most of your work in that zone when…

I'm a cyclist, 100km without much effort, but a year ago I started running and it was super hard. The muscles are used differently, the body get impacted with every step and it takes some learning to find the right speed to reach whatever your target is. Pain kills the fun, the only way to succeed is to start slow and on short distances.

My goal was strengthening hip (one side has a three plates and a few screws in it) and knee mobility, with losing weight being an extra that I only reach this spring due to diet changes. I did find my Zone 2, where I can chat with a running buddy, and slowly extended the distances I run: Now 5km at 5:40m/km are the norm and 10km is just as possible. Injury-free so far and no ambition for a Marathon. The thing I now have to work at is the cadence which I (at 193cm) had trouble with on the bike as well, but shorter strides at a higher cadence are important to prevent knee injuries.

Whatever you do, I think sticking to it at least three times a week so you look forward for the next run, feel well during it and keep healthy. This is more important than beating records or running insane distances. Those goals are for those with the right genetics.

Re: Cardio fitness is a strong, consistent predictor of morbidity and mortality

#319

Earlier quoted context omitted.

> people can make pretty rapid weight loss without eating Your suggestion is not sustainable. A staggering 90+% of people regain all weight loss a year after their diet ends. Seriously, who is not going to eat for two days per week? Your mental health would be a wreck. Can you do it? I cannot.

90% of people regain weight because they go back to eating like they have a death wish. I think conflating between mental health and eating is at the heart of the obesity epidemic. Nobody will die if they skip a few meals. They will suffer some moderate discomfort depending on how much they fixate on it. I can go a week without eating and a few days is trivial. The longest a human has gone without food is 381 days an…

Please do not assume your experience is universal. You simply cannot know how it feels for other people to be hungry, it might be a completely different feeling than what you get.

Re: Cardio fitness is a strong, consistent predictor of morbidity and mortality

#320
post #71

Earlier quoted context omitted.

reminds me of the bicycle helmet stuff. There was a ted talk that said bicycle helmet laws would kill more people than save. The reasoning was preventing people from riding would also prevent increased fitness, and more lives were lost from that than saved from accidents. EDIT: I think this one: https://www.youtube.com/watch?v=07o-TASvIxY

This sounds ridiculous until you go to Amsterdam see that few wear helmets there. And everyone is cycling. They might be more inclined to cycle because they don’t need to wear a helmet. After years of cycling with helmet you get so used to it and it doesn’t bother you. But how many skip the bike because they never got used to wearing a helmet?

Biking in Amsterdam is leagues safer then biking in most places in the US, though. The risks are different. Helmets aren't as important if most of your crashes are going to be with another low-speed, mostly-soft bodied cyclist. Traffic and pedestrians are pretty separated and you have your own lanes to cycle in. I'm also pretty sure that a lot of biking is convenient: The local grocery store is just a short bike ride but it'd take 15 minutes by car.

Most biking in the US is biking shared with cars. You probably won't have a bike lane. Most likely, you aren't commuting or going to the grocery store - the grocery store might take 15 minutes of driving but 30 minutes of biking - if you can even go the most direct route legally. Longer biking sessions generally means more risk. I'll take the helmet in places that I must defend myself against automobiles on an unsafe path.

Post reply on HN