How to avoid gaining weight over Christmas and New Year

We might as well rename the last month of the year. It's not December – it's Silly Season. Christmas parties and client gatherings roll into big weekends. Then there's Christmas Eve, followed by Christmas Day, Boxing Day, and the obligatory New Year's Eve blowout. It all means food, food, and more food … then add drinks.

'Tis the season to truly indulge? If you do, there's a cost – either extra time at the gym or to Boxing Day Sales for a larger belt. Just how much does it cost? Extra food is extra calories which must be burned off via movement.

Here are some party treats and what it's going to take:

Beef pie

If the festive season had a food pyramid, party pies would be its own food group. After the waiter swings by a few times with that tray, you've had an equivalent of a game day pie, equal to 413 calories (1720 kilojoules).

To burn off that slurpy-gravy-goodness, you (the average lad and lady) will need to row at a vigorous pace for about 45 minutes – that's serious effort for one dripping piece of pastry.

Three extra drinks

"Come on, just a few more pints / wines." How many times does that echo throughout Australia this month? Three pints is an extra 615 calories (2598 kilojoules).

Liquid gold will stick to the belly and hips unless you sweat and swear it out with exercise. A high intensity spin class (45 minutes on a bike) will do the trick, if you have the energy to work it off with a hangover.

Banana bread and energy drink

You arrive at work feeling hungry and dusty, so it's time to fill the belly and increase the energy. One slice and one big can equals 414 calories (1749 kilojoules).

Run, run, and run. Hit the treadmill at lunch for about 35 minutes at an 11km per hour pace to negate all those empty calories.

Espresso martinis

The night carries on, and you need a picker-upper. Two espresso martinis are your poison, but they'll add 570 calories (2407 kilojoules) to your daily intake.

Hit the pool soon after because it's going to take over one hour of intense swimming to work off that sweet caffeine.

Egg nog

What a taste. It just oozes the seasonal spirit. The cream, the sugar. You love it. Yet you'll hate the 334 calories (1413 kilojoules) in a nice sized glass, and a CrossFit WOD will be required which (if you're lucky) might have you vomiting those calories and hitting the showers early.

Pavlova

One slice of pavlova is so, so good – who can say no to seconds? Get ready to walk for ages, as it will take two hours at a 6km per hour paces to burn off the 654 calories (2762 kilojoules) tacked on to that sugary goodness.

Keeping on track

I'm aware that calories-in to calories-expended is not an exact science to keep the weight off. However, with extra food and drink comes extra weight. You don't have to be perfect throughout the season, but you need to sacrifice a little so you don't stack on the kilograms and hit the ground rolling in 2017. Here are a few tips:

BYO dinner

If you know party food with little health factor is on the menu, then bring leftovers from home and eat early. Nobody will know (or even care), and you'll avoid all the processed, holiday junk.

Look outside

The northern hemisphere has winter. We are lucky to have sun and warm temperatures. So, plan some hikes, outdoor workouts, and ocean swims. You have time off work and plenty of time to get some fitness going throughout this month.

Drink water

I won't play Grinch and advise a water between every drink but water pre-meal fills us up, so you're likely to eat less. Water saves a hangover. And water can replace a few late night wines, which might save you from becoming the company arse. Two or three drinks to one water ratio. Please?

Don't be the company arse

Last week, I looked from my apartment balcony as sizeable boats unloaded corporate party goers. There he was – face down, passed out on a giant white swan floatie. It was 4.15pm on a Friday. Sure, it's funny at the time but it's bad for your health and your career.

Plan your deviance wisely

Office Christmas party, Christmas Day, New Year's Eve. Choose a few days and truly go for them. Yet you might have to say no to some other days. Commit to a schedule where you plan healthy meals and efficient workouts around those festive events.

This Silly Season, I hope you enjoy some naughty treats just as I will. However, turning Dad bod into Santa bod is going to hurt long into the New Year. You've got two choices – make some sacrifices this month, or start 2017 with the world's most popular resolution: I've gotta lose some weight this year.

Passion for lifestyle change is the cornerstone for everything Michael Jarosky does. A Sydney-based personal trainer, he cajoled thousands of Executive Style readers to undertake his 'Cut The BS' diet, and champions a charity weight-loss event, Droptober.

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