But, run 100k a week for 10 years, and you may not need many more calories to keep it up than the 3x weekly jogger, because your body has adapted. I guess that is what the study in the article is observing.
If you do 1h a week for half a year you are potentially at about 3 Lb or 2% body mass loss.
If you however you do 2h each weekday you are close to a potential loss of 30 Lb or 20% of weight.
Now obviously you could argue that the first case won’t work to lose weight and that you’ll just subconsciously eat a bit more to offset it, and the outcome isn’t even that large to begin with and would disappear in fluctuations of your weight unless you are consistent about hydration levels and food intake prior to stepping on the scale. But in the second case you will definitely end up changing your weight even without changes to your diet.
Anecdotally and n=1, but I highly doubt this assertion. I lost significant weight without a diet change going from little exercise to swimming 2km 5 times per week.
I think what give people the impression of exercise not affecting the scale is that a little exercise won’t show. If you do yoga once per week, you might have the mindset of “I’m active, I do yoga, why aren’t I losing weight?” But it’s just not that much when you calculate the calories. Even at 10km of swimming a week, it’s not like I was shredding the weight instantly. I was maybe losing a bit more than 500g per week, which isn’t even significant enough to show if you aren’t consistent about weighing at the same hydration level, but over a couple of months and staying at that level it definitely shows. Now in comparison most others I know who casually swim would do maybe 400m once a week at a comfortable pace. That’s enough that you answer in a question are that “yes, I’m active, I swim each week” but not enough that you’ll significantly change your weight from it.
I think the saying shouldn’t be “you can’t outrun a bad diet” should really just be “you have to run a hell of a lot more than you think to outrun a bad diet”