I can remember the days when, as a woman, I used to smile complacently when multi-tasking was mentioned. There'd be little quips such as 'We know guys can't think of more than one thing at a time. Ask them something really important when they're watching TV and you'll never get an intelligent answer.'

But guys, you have the last laugh. There is now a heap of research to show that constant multi-tasking is not so smart - and I've participated in some of it.

Researchers such as NY-based Basex give us some startling data. They're a research company devoted to helping us navigate through today's minefield of knowledge management in our over-informed world. Their Chief Analyst, Jonathan Spira tells me that most knowledge workers lose about 28% of their day or 2.1 hours a day to constant interruptions.

It's not the interruption itself, which might only be very brief, that's the issue.

The first problem is the switching time. Add up all the seconds in a day spent changing mental gears as we move from task to task and we discover serious productivity loss.

The amount of lost time is related to the length of the interruption. Basex have identified that it takes between 10-20 times the length of the interruption to get back refocused on the previous task. In other words, a 30 second interruption can easily take us off-task for 5-10 minutes. But it gets worse.

The next problem is the number of times we don't get back to the previous task. As we all know, once our train of thought is broken there's a very good chance that we return to a prior activity.

Don't believe me? How many open emails and applications do you have on your computer right now? Or how many items of paper or equipment are in your immediate space, waiting for you to decide where to put them? What actions or activities are awaiting a final decision or completion?

And what happens when we live constantly in a world where everything is going at warp speed, with multiple distractions? Think of many modern offices. There's constant low-level (or sometimes high-level) noise and movement. Phones ring, people walk by, emails ping as they arrive, and conversations happen all around you.

My friend and associate Steuart Snooks in Melbourne, who specialises in helping people conquer email overload, had this to say: 'A common result is pseudo ADD, a term coined by two Harvard psychology professors to explain addiction to the bombardment of information. They've noticed that many people experience shortened attention span because of the forms of communications used today. This has a sustained negative neurological effect as well. It isn't an illness; it's purely a response to the hyper-kinetic environment in which we live.

'So when a manager is desperately trying to deal with more than he can possibly handle, the brain and body get locked into a circle where the brain's frontal lobes lose their sophistication. We get black and white thinking and we start to lose perspective and shades of grey. People with this sort of difficulty struggle to stay organised, to set priorities and to manage their time. They experience a constant low level feeling of panic and guilt.'

Paul Chin is another commentator in this issue of information overload. He's quoted as saying: "Rampant multi-tasking and the deluge of available information has ... created a paradox. The more we try to do the less we get done. And the more inundated we are with information the less time we spend absorbing it."

Perhaps women can cope a little better than men when it comes to multi-tasking. But - it's not smart to even try. Both genders get frazzled, exhausted and frustrated when they've got too many things going on at the same time. And they lose hours in a day.

So - go the people who stay focused on one thing at a time! Keep it up. You'll get your work done faster than your multi-tasking colleagues.