I think he may have been saying this sarcastically.

Maybe linear would be more appropriate than incremental as in: not all improvements in our lifestyle will have the same impact on our health. If you stand up and move every 20-30 minutes but you eat sugary and fatty food all the time, the improvement of your small breaks will be marginal in the long run compared to all the other problems you'll get. On the other hand, if you sit down all day but eat healthier food (good fat, more proteins, less calories, fibers), the benefits of this lifestyle will be greater.

Stress management and reduction also comes to mind (of course taking a small break and moving around can help that).

I find that if I restate someone's argument absurdly and preface my statement with "I agree", people are less likely to see me as an antagonist and more likely laugh at themselves. (This is actually one of my favorite tactics for productive disagreement.)

I suspect that was the joke.