Whatever you indulge in at the table, you'll pay for at the gym.
Every time you eat something bad - whether it's chocolate, burgers or chips - you know you're going to have to work harder to burn them off.
But one of our favourite diet cheats is to pig out on McDonald's - even though we know it could scupper our diet.
There was actually research published suggesting McDonald's could be just as effective as your post-workout supplement, according to researchers who tested their theory out on cyclists.
But the rest of the time it's probably not going to do your abs any good at all.
Luckily there's a new website that lets you know how long it will take to burn off that massive pile of fast food you just ate.
So we thought we'd check out some of our favourite Maccies meals to see just how much exercise we're going to have to do if we wolf down a sneaky one after a night out.
For an average Irish man weighing 83kg this is what the results came back as....
Large Big Mac Meal....
You can't beat a classic Big Mac. It's also impossible to resist going large on an extra value meal when you rock up ravenous at McDonald's.
Be prepared to put some graft in on the treadmill once you've scoffed the lot.
The website says the calorie total for Big Mac, large fries and a large Coke comes to
1,330. You'd have to do more than
two hours running to get rid of those extra calories.
If you throw in a McFlurry for dessert, you're going to have to be out pounding those pavements for an
extra 50 minutes.
Sausage and Egg McMuffin and a latte...
Breakfast is the most important meal of the day - and when you're late for work, tired as hell, and hungry enough to eat a buttered brick - there's only one place to grab some quick morning sustenance.
A sausage and egg McMuffin contains more calories than you'd imagine. This two-piece breakfast will add
900 calories to your daily intake, according to the site.
That's nearly
two and a half hours of dancing, if you're into that kind of stuff. Better get throwing some shapes at the club later on.
Twenty chicken nuggets, fries, and a milkshake...
Everyone loves chicken. But we're greedy, so obviously only 20 nuggets will do. And what better way to wash it all down than with a milkshake?
It might not be everyone's ideal McDonald's order, but it's what our cheat meal dreams are made of.
But you'd better enjoy the hell of it while it's tickling those tastebuds, because you'll be putting some hard yards in later on in your spin class.
The website says your calorie total for this meal would be
2,000, so unless you're planning to survive off just 500 more calories for the day you'd better get that gym gear out.
You'll have to stick around and do
three hours straight on the bike to shift this lot though...
*This article first appeared on JOE.co.uk*
