To call Clyde Thomas a high performer would be an understatement. As CIO and executive vice president of global operations and technology for eFunds, a $US600 million financial services company, Thomas logs nearly 70 hours a week on the job. He oversees five data centres in the US and two abroad, managing 450 people who serve 6000 users overall. He is responsible for the company's software engineering, call and data centres, and security. He is also building new enterprise projects in China and Eastern Europe.

Thomas typically works from 5.30am until 6 or 7pm, answering all 300 of his daily e-mails before heading out for the 30-minute drive home. Rough days stretch longer. Some nights he'll participate in an overseas conference call with network administrators and other IT managers at 2 or 3am. Then there are emergencies, which require his immediate attention.

"We do millions of transactions every minute. If something goes wrong with our technology, I want to make sure I'm involved in fixing it," he says. "Do I like handling conference calls [after midnight]? No. But if you're running operations for a company of this size, you do what you must."

Thomas is not the only one working nearly 70 hours a week these days; CIOs are racking up serious hours in just about every sector. Recruitment firm Harvey Nash released a March survey of 172 CIOs that found nearly 20 percent worked more than 56 hours a week. About 4 percent put in more than 65 hours a week.

CIOs have always logged long hours; it's what you do in IT. But now these work habits dovetail with the rise of "extreme jobs". The Centre for Work-Life Policy (CWLP), an independent research organization that works with employers on work-life guidelines, released a study last year that defined extreme jobs as those in which employees work at least 60 hours per week, receive hefty salaries and feature at least five of 10 characteristics from a list that includes availability to clients 24/7, an unpredictable flow of work, lots of travel and an inordinate scope of responsibility (see "Are You Extreme?", end of story). Study authors Carolyn Buck Luce, a principal and global pharmaceutical sector leader with Ernst & Young, and Sylvia Ann Hewlett, president of the CWLP, call these jobs "extreme" with a nod to extreme sports such as the Ironman triathlon and bungee jumping that require participants to risk life and limb to compete at the highest levels.

While the study didn't specifically look at the CIO position, the job easily meets most of the extreme criteria. The CIO role may in fact be among the most extreme in business, says Luce.