Let's be honest: New Year's resolutions are almost always a big waste of a time, and we all know it.
They mostly fail because they're too vague – it's great you want to get fitter and do more exercise, but hard to translate those good intentions into practical steps you can do every day.
The internet has come to your rescue by providing free and idiot-proof beginners' programs. Pick one that best suits your fitness goal. Try to work on it most days of the week. And by the end of 2020 you might be benching your bodyweight, doing one-handed push-ups, or twisting your legs behind your head.
Most people stop using their gym membership because they're unsure what to actually do when they get into the gym. Starting Strength is a solid entry to weight training – and you don't even need a gym, if you invest in a barbell and weight plates to use at home. (You might get lucky and find a cheap set on Gumtree.)
The novice program will teach you basic lifts such as the squat, deadlift and bench press, and there are tons of free online resources supporting the workout. If you're a total gym novice, you're guaranteed to make fast progress thanks to a concept nicknamed newbie gains.
Couch to 5k
Some folks claim to find running genuinely enjoyable and almost meditative. I am not one of those folks. But if you're keen to join their ranks, start with the renowned program dubbed "C25k".
It's designed to counter the mistake made by almost every new runner: going too hard, too soon and collapsing back to the couch with aching shins, ankles and quads. You'll start out mostly walking, with a little jogging thrown in, then gradually up the intensity over nine weeks until you're running 5km non-stop in a tidy 30 minutes.
Once you've conquered the beginners' program, the C25k site also offers resources that will help you finally achieve your "run City2Surf" goal – or even finish an ultramarathon, if you're that crazy.
Do you want to be one of those show-offs who dazzles with one-handed pull-ups and dangling horizontally from poles? Bodyweight fitness – aka calisthenics – is how you get there.
A terrific starting point is Reddit's bodyweight fitness community, which provides a free beginners' program that's incredibly thorough, regularly updated, and (be warned) much harder than it looks. The 1.2 million-member community is also on hand to answer questions, provide motivation, and congratulate you on your planche progression.
Yoga with Adriene
Every year I vow to do more yoga, and every year my yoga mat ends up gathering dust in my bedroom corner. That's because I can rarely find room in my day (or in my budget) for regular yoga classes.
So I've explored a lot of online yoga classes, and can tell you that the best free ones are on Yoga with Adriene: the YouTube channel of US yoga teacher US yoga teacher Adriene Mishler. She's easy to understand, and doesn't stray into the woo-woo that dogs so much yoga.
According to Sam Downing, the secret to wellbeing is just to keep it simple. A qualified personal trainer, fitness instructor and nutrition coach, Sam is also a writer focusing on everyday health.
Follow him on Twitter.