According to research, monitoring a constant influx of email leaves wonks throughout the UK feeling tired and frustrated. And 'email stress' leads to us all being less than productive, to boot.

Researchers from Glasgow and Paisley universities found that more than a third of office workers check their inboxes every 15 minutes. Which leaves me to ask - what on earth are they doing for the rest of the time? I break out in hives if I go five minutes between refreshing Outlook. And I've had to fix a post-it note to my home computer that reads: "no-one likes a post-pub email".

But as only 64 percent of respondents said they looked at their inboxes more than once an hour, perhaps I'm just being needy.

Or not. When the researchers fitted a monitoring device to PCs, it turned out that workers were actually viewing emails up to 40 times an hour. The beggars. But it's not just idle browsing - only 38 percent of workers were cool enough to wait a day or longer before replying to a business message.

Indeed, a third of respondents said they 'felt stressed' by the volume of emails and the need to reply quickly. And a further 28 percent felt 'driven' when they checked messages, because of the pressure to respond.

Workers even claimed to feel 'invaded' by email messages interrupting as they tried to concentrate on work. (Interestingly, female workers feel under greater pressure to respond to email than their male counterparts.)

And this I understand. There's little more sinister than that email thudding on the digital doormat and lurking there, a malevolent reminder of work you haven't done. And it can be tough not to down tools and switch applications to find out whether an email is urgent.

So I guess this is where email reduces productivity. In fact, if I've got a deadline I'm apt to quit my email to aid my focus.

Karen Renaud, a computer scientist at Glasgow University, and Judith Ramsay, a psychologist at Paisley University, surveyed almost 200 workers.

They said: "There is evidence that email can exert a powerful hold over its users and that many computer users experience stress as a result of email-related pressure."

Ms Renaud said: "Email is the thing that now causes us the most problems in our working lives. It's an amazing tool but it's got out of hand."

Which may contain a germ of truth. But I am still unsure of a couple of things: how on earth did people waste time at work before the internet and email? And what did people actually do, (apart from smoke at their desks, use hatstands and ogle the typing pool)?

Send me an email if you know (but mark it 'not important').