Hacker News Reader

Comment by KennyBlanken | Hacker News Reader

A few hours on my bike can be 2,000-3,000 additional calories over base metabolic rate. That's not based on made-up calories but actual work from a power meter on the bike.

"You can't exercise your way out of a bad diet" - literally not true for a fuckton of endurance-sport athletes for whom the challenge is eating enough calories.

It's 100% true for people who think exercising for 30 min means license to eat whatever.

> So a good diet: takes less time than exercise, reduces calories more, and can save money

Yes, but endurance exercise over an hour or two brings its own advantages health-wise.

The real takeaway is that there are no absolutes.

View on HN

One of the cruel aspects of endurance sports is that they suppress your appetite. You can go out and burn 6000 calories in one race, spend the whole time thinking about all the delicious food you're going to reward yourself with, and then you get there and have zero desire to eat. You sometimes can't even start refeeding until the next day.

Feels to me like pushing your body to extremes is akin to a metabolic shock and your system rebooting in another operating mode. Probably needs another reboot to go into regular mode, so your apetite will also vary in the meantime

I always feel there are some methodology issues in sports science studies like small sample sizes or strange metrics.

While I do agree with you that sustained, high level activity requires and burns more calories, I think that the advice coming out of there, exercise is less efficient than diet for weight loss, is going to absolutely be true for the majority of gym goers who quite frankly are phoning it in whenever they work out.

Like, for example, an olympic swimmer may eat 5000-10,000 calories in a day, but they are spending around 4-6 hours a day in a cold pool training at a world class level (body needs to keep warm somehow regardless of effort.) But a normal person may only swim for 20 minutes at a much gentler pace. This person should still be eating in line with calorie guidelines and macros for age/sex.

The reality is that diet needs to be flexible based on results. Not losing weight? Eat fewer carbs or calories. Feeling tired and worn out? Eat more or exercise less based on your physique and goals.

For the majority of regular people feeling tired and worn out is more likely to be caused by lack of sleep and too much booze than by lack of food or excessive exercise.

I meant more from training hard for long term. Most people are not at this level or pushing that hard. Normal people would definitely benefit from lifestyle changes outside of the gym if they are tired and worn out.

If I remember correctly, Olympic swimmers are NOT spending 4 hours a day in the pool, and certainly not 6.

https://www.reference.com/world-view/michael-phelps-training...

A couple of years ago I took swimming lessons from the Swiss butterfly swimming champion and he said he trained about 20 hours a week and that to get to Olympic levels, he'd have to train even more. For swimming it's possible to train much more than in other sports, because it doesn't do as much joint damage, because you're in water.

I spent years failing to lose weight through diet. I took up endurance cycling and in one day (13 or 20 hours) I burn off a kilo or more, even with the increased eating. Afterwards I'll put that back on in about two months, but as long as I keep doing one or two of these events every month I come out ahead.

I don't know how things are for anyone else, but it worked for me, shrug.

I had very similar experience. I lost weight with no much additional effort when I started to do a lot sport. I did not focused on food much, I was doing sport for weight loss unrelated reasons. And it dropped.

Attempts to loose weight by diet only all failed. To make it worst, there is also aspect of most common diet advice being plain wrong. It focuses on calories too much. It completely ignores what your body needs, so you end up in nutritional deficiency - this kind or that kind. And that will affect a lot and eventually you will stop diet and start to feel so much better and healthier after stopping it.

> I always feel there are some methodology issues in sports science studies like small sample sizes or strange metrics.

The calorie stuff is from both oxygen and deuterated water studies. You burn the same amount of calories and your system just shunts them around. The science on this is one of the few things in nutrition that is quite solid.

This has the effect, for example, that if you exercise a lot, this actually suppresses your immune system making you more likely to get sick.

> A few hours on my bike can be 2,000-3,000 additional calories over base metabolic rate.

Are you sure? 2000 kcal in 3 hours is 770 watts of power output.

Edit: Wikipedia [0] says "During a bicycle race, an elite cyclist can produce close to 400 watts of mechanical power over an hour and in short bursts over double that - 1000 to 1100 watts; modern racing bicycles have greater than 95% mechanical efficiency. An adult of good fitness is more likely to average between 50 and 150 watts for an hour of vigorous exercise."

[0] - https://en.wikipedia.org/wiki/Human_power

You are forgetting that the human body is nowhere near 100% efficient at burning fuel to put power into a pedal. To produce 400 watts of mechanical power, the body consumes about 4 times that amount of fuel (25% efficiency). Consuming 2000 kcal over 3 hours is thus closer to the more realistic 200W of power to the pedals, and even the higher ranges make sense if he's a good athlete. See this article: https://www.welovecycling.com/wide/2020/05/14/how-to-convert...

> You are forgetting that the human body is nowhere near 100% efficient at burning fuel to put power into a pedal.

I'm not, because the parent poster explicitly said "That's not based on made-up calories but actual work from a power meter on the bike."

Which seems absurd, hence my comment.

After a 2000 kcal high intensity cycling workout I'm so tired that I don't even feel like eating. I have to force myself to eat something because I know I need it for recovery.

Looks at wahoo kickr in corner

Hello old friend, we meet again.

Reply on news.ycombinator.com