I know this isn't rigorous but it definitely matches up with my personal experience -- I'll be hungrier, often ravenously so, after strenuous activity.

I have no apetite at all after biking for two hours. However, if I drink any diet soda or piece of candy with sweetener, I will be ravenously hungry in 10 minutes. Has always been like this so I stay away from that stuff.

My exercise is a game called Turf. Mostly played in Sweden where there are a lot of zones close by. I bike quite relaxed for 1-4 minuts and stand still for 20 seconds in the zone, then repeat until next zone. It's a bit harder during winter with all the snow though. I have done nothing to my diet and lost about 20 kilo the last year. The GPS says I traveled about 3500 km the last year at my slow pace.

100% this for me. I do intermittent fasting and my first meal is around 2pm. I do brazilian jiu jitsu around 6-9 and skip dinner. When I come home Im not hungry at all for at least an hour. Ill get a little hungry and if I eat or drink anything, the floodgates open and I cant stop eating. It is better to go to sleep a little hungry.

I try to have a 500 calorie deficit. If I have more than about 500 (say 1000) Im fine that day, but the next day Im ravenous and tend to overeat.

Oof this was me yesterday. Ate one large meal and snack between 2pm and 5pm because I had a work event in the evening. Got home around 9:30pm and really wanted to eat something and I almost did.

Drank a few cans of seltzer and wound up staying up doing emails and chores until 2am. Woke up at 9am today and I'm feeling a bit hungry at 11:20am, but even if I eat something now, it will be a net negative compared to what I would have eaten last night.

After a long bike ride, apart from being much hungrier than usual, food tastes better. Mediocre food becomes good, good food becomes the best thing you've ever eaten.

Yeah, that's the way I've felt when I've gone for a hike. The food tastes better and I will happily eat an amount of food that I later regret.

The activity makes a big difference for me though. Running for example tends to not have a major impact on appetite.. sometimes I feel like it actually lowers my desire to eat. That's based on relatively short runs though (45-90 mins of activity). I don't know how I'd feel after a marathon.

If I ride a bike for 3 hours, I feel like I could eat a horse.

This matches my experience. Swimming or biking makes me hungry. Running a reasonably long distance (say, 7+ miles) makes me a slightly nauseous and not hungry at all. Maybe it's because running causes more jostling and/or beats up non-muscle parts of the body more?

I have a bias towards the idea that we are very different, and it really depends on many unknown factors that apply only to one specific individual.

I also have that gut feeling, mind the pun. It stands to reason to me that since metabolism is incredibly complex, any slight variation in any of the parameters can lead to significant differences observed at an overall operational level. It's also very obvious people are reporting a wide range of experiences for the same activity

We're not _that_ different. And a lot _is_ known. There isn't anyone on earth with incurable obesity.

I know, anecdata, but on my off dates (I go swimming in the early morning three days a week) I have to fight not eating breakfast early and then needing lunch and dinner in the evening.

On my swim-days I have no problem with a late breakfast leading me to be able to skip lunch and enjoy my dinner.

But I have no other insight as my own experience.

It has a lot of backing when you look at people changing jobs without gaining or losing weight. We think of exercise in terms of X minutes on a treadmill, but people working long days of physical labor can more than double their daily caloric needs and will eat accordingly without prompting.

There where plenty of old jokes about lumberjack breakfasts and people eating skills tall stacks of pancakes. These guys weren’t trying to gain or lose weight just keep going for another day of hard labor, but when you start talking 6-8,000 calories per day it’s an insane amount of food.

Also, some of the feedback mechanisms involved are quiet slow and can take weeks to kick in. Your body doesn’t need to balance things every day as gaining or losing significant weight takes time.

Also anecdotal, but I’m not an athlete (like, the inverse of an athlete, I’m overweight and don’t move enough) and moderate exercising does, in my case, suppress some appetite. I eat les after exercising.

My 2 cents theory is that it suppress the "stress induced" appetite.

It might also increase dopamine. I have ADHD and there are two things that let me focus better and feel less hungry: stimulants and exercise.

Oh ! I have ADHD too so maybe it’s that.

If you are low on sugar (therefore hungry) for a while, your body will start burning fat (lipolysis) to restore sugar levels. This will suppress apetite.

It's easy to experience, although it can take longer for lipolysis to start if you're not used to. Of course, eating sugar during or before exercise delays it.

Some levels, yes, appetite-suppressing. When appetite returns, it can be with a vengeance.

I think it depends heavily on what you do. When you run, you tend to eat less, me definitely. When you weight lift, do body weight exercises, do anything that builds muscle, you need to eat. Personally I get more hungry about HIIT too.

And that additional eating is not a bad thing either. It is body needing supply to build muscles. For most beginners, that is a good thing.

Yeah, this is me. I naturally eat a lot less when I am exercising than when I am not. I'll often exercise in the morning and then have no desire to eat until dinner time.