SOH RUI YONG, 27
2015 and 2017 SEA Games marathon champion
Firstly, set a goal! It can be anything from losing 10kg by the end of the year to improving your marathon time by 10 minutes.
Another thing you can do is register for a fitness challenge. This will keep you motivated.
I personally look forward to local races such as the Safari Zoo Run (12km), Army Half Marathon and the Standard Chartered Singapore Marathon. They give me something to work towards, and keep me motivated to get out of the door every day to train.
To add spice, you can register for overseas races such as the Gold Coast Marathon in July. A fun "runcation" is always bound to get you motivated to train hard.
If you are able to, it is good to seek advice from an expert. Enlisting the help of a coach can keep you motivated, avoid injury and even allow you to meet other athletes you can exercise with.
Finally, always remember that regular exercise reduces blood pressure, preserves your youth, increases work efficiency and improves your sex life.
So what are you waiting for?
MUHAMAD RIDHWAN, 31
International Boxing Organisation Intercontinental champion, World Boxing Council's world No. 28 super bantamweight
The first thing you should do is have a fitness goal unique to you.
The second thing you should do is talk about it. Once you do, the people you share your goal with will be proof of the promise you made to yourself.
Each time you feel lazy and decide to skip training, you will think about those you shared your goal with, and won't want to give them the opportunity to say, 'I knew you would give up.'
Also, come up with a training plan or choose one, and stick to it.
It does not matter if someone else is progressing faster than you are. This is a battle with yourself.
Enjoy and trust the process. Be patient, but also persistent.
Create a playlist of your favourite workout songs, a list of motivational quotes or a highlight video of a sport or athlete you admire, and use them as inspiration to get moving.
CHARMAINE SOH, 28
Netball national captain. 2012 and 2014 Asian champion, 2015 SEA Games gold medallist
People have different reasons for wanting to start exercising; for some it's vanity, and others to get fit - for me it's both - but whatever your reason is, just get started.
I want to fit into my dresses and look good, to improve my stamina, and so I don't get fat from the desserts that I love! Because of all that, I work out on my own.
There are various things you can do, even at home by yourself. For me, it's swimming and cycling because they don't put too much pressure on my joints.
Core exercises are a good place to start, and I like to do static holds (planks), toe touches, the dying bug, and also getting into push-up position then bringing my knees towards my nose. I add squats to that too, in the workouts that I do two to three times a week.
That helps me keep in shape, supplementing the court sessions that the netball team have, but we can't forget that diet is important too.
I have a sweet tooth, but to make up for that, I stay away from fried and oily foods, and I cut down on sugary drinks and carbs at night.
I've even got my mother to start eating healthier and walking more, and I will continue to encourage her!
HARISS HARUN, 28
National football captain
It's important to set a long-term goal, but also give yourself smaller milestones to hit. You may want to lose 10kg, but maybe set weekly achievable goals like working out three times a week. And even while you do all this, it's very important that you reward your perseverance - we're not robots.
Being a pro footballer is a 24/7 thing, and I watch what I eat, how I train on my own, and even how much I sleep - sometimes my wife is shocked that I'm sleeping so early! - but I still have a teh tarik and a late night now and then.
I pay a lot more attention to my diet than I did maybe three years ago, but it's very important to have cheat days so that you can maintain the motivation to keep going, and not give up after a month - find that balance for yourself.
And if you're not sure, get some help. I have a personal trainer friend, who guides me in football-specific exercises that I need to improve for areas that are problematic for me personally.
Remember, it's about balance, so that things don't get tiresome or boring.
•Compiled by Shamir Osman and Sazali Abdul Aziz