We’ve all been there. You spend an hour in the gym, and before you even reach the change room, you start thinking about our favourite takeaway meal – after all, you’ve earned it!

Before long, you’re tucking into a super-sized meal. Then the guilt hits: what was the point of exercising to burn all those calories if it just makes us eat even more calories?

But while this might be a familiar pattern, it’s not necessarily a super-sized hunger at play. Let’s see what the science says.

How exercise impacts our appetite

While many people report that exercise makes them hungry, the science is more nuanced.

In the short term, a bout of exercise can actually suppress appetite. A meta-analysis of 20 studies found exercise reduced the hunger hormone ghrelin while increasing hormones associated with fullness, including PYY, GLP-1 and pancreatic polypeptide.

But this effect is temporary. A more recent systematic review and meta-analysis found exercise suppressed appetite initially, but this effect wore off 30–90 minutes later.

So exercise isn’t an appetite-suppression strategy. Rather, there appears to be a short window after exercise when our appetite may be dampened before it returns to normal.

There is an important distinction between what happens after one workout and what happens when we exercise regularly.

A systematic review of exercise training in adults who were above a healthy weight or who had obesity found a small increase in hunger levels while fasting.

However, there were no........

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