I'm afraid money can't help here but there is something you can do and it will keep you fit, help keep your heart in good health, keep your weight in check and make you feel good, not just while you do it but for hours afterwards.

More importantly, it will try to let you enter old age in good physical shape and allow you to enjoy your third age to the full. Oh, and the good news - it's free!

The answer, I am sure you knew it all along, is exercise. No, don't shy away for there is no getting away from it, if you want one sure-fire insurance that can make old age a doddle then it has to be regular exercise.

In our hearts, of course, we know this. We all realize that we are meant to lead physical lives and that if we don't our bodies start to let us down. So, and here's the bottom line, how little exercise can you get away with to make sure you are fit enough to enjoy old age?

This is a hard one to answer; some people talk about a regular 60 to 90 minutes of exercise a day. Now, I don't know about you, but that is a whole big slice of time out of an already crowded day so there has to be a better way!

To be honest, the hour-and-a-half a day pundits are right but they are looking at it academically and in ideal circumstances. They are not looking at it from the viewpoint of an ordinary, and thus time challenged, person living in the real world of today.

But, in reality, fitness is in small things, and really it's in physical movement. If you can find something to keep yourself moving, and moving fairly energetically, for around 30 minutes or more most days then you will be well on the way to keeping your fitness level up.

It's not that you don't need more but that amount will keep your body 'ticking over'. Of course if you want to do more, then the result can only be beneficial.

The other thing to know is that you don't have to do the 30 minutes in one go. You can split it up into two 15 minute slots anywhere in the day or, if you really have to, into three 10 minute slots.

The exercise that you do has to be fairly energetic, enough to make you sweat and breathe a little hard but it can be the sort of exercise you can fit into your life. It can, for example, be a brisk walk or some hard yard work or something simple and fun (and my favorite) like stopping what you are doing and dancing to music.

Or, if you want, you can use a treadmill or any other exercise apparatus, it really does not matter what you do so long as the end result is physical!

See if you can do this for around four or more days a week and now your insurance is starting to look good.

The whole point about regular exercise is that it starts to become a habit and, once that happens, you find that you naturally keep yourself fit without having to constantly remember to exercise.

Now, as you get older, just keep it up and remember that you don't stop your daily exercise ever because it's the best life insurance that you can take out!