It's 10.30am, and Fernando, a civil servant in his late 40s, sits down to a café con leche, the sports pages and a cigarette in Madrid's Plaza del Rey. At work since 9am, he is taking his routine morning break.

It's a ritual you see everywhere across the capital: friends and colleagues gather in the mid-morning, coffees are ordered, noisy conversation ensues, and 20 minutes later they're back to work.

But these leisurely coffee breaks may soon come to an end, following a vote by a parliamentary commission on Thursday recommending that Spain turn its clocks back an hour and introduce more regular working days, starting at 9am and ending at 5pm.

The cliché of Spain's late-rising, long lunches and afternoon siestas may prevail in the mind of foreigners, but the reality for most Spanish workers is a long and disjointed day.

"I'm normally in the office until about 8pm," said Fernando, explaining the long hours worked by the average Spaniard. "I could take two hours for lunch, but mostly I just have an hour, and often eat at my desk. I certainly don't take a siesta."

In part, Spain's chaotic working hours come down to a historical anomaly. In 1942, Spain's dictator, General Francisco Franco, changed the country's time zone to coincide with Germany's in an act of solidarity with his fascist ally. And it has never gone back.

"Because of a great historical error, in Spain we eat at 2pm, and we don't have dinner until 9pm, but according to the position of the sun, we eat at the same time as the rest of Europe: 1pm and 8pm," explained Professor Nuria Chinchilla, director of the International Centre for Work and Family at the IESE Business School. "We are living with 71 years of jet-lag, and it's unsustainable.

"If we eat at 2pm, and dine at 9pm, then logically we ought to start work at 10am. But we don't do that, we start earlier, so our mornings are far too long. That's why people need a coffee break, because they can't wait that long to eat. So we lose time in the morning and have to work even longer in the evening." She believes that changing Spain's time zone, combined with a more rational 9-5 working day, would be of huge benefit, and cost nothing.

At the head of the campaign to bring Madrid into line with London is Ignacio Buqueras, president of the Association for the Rationalisation of Spanish Working Hours. He has been campaigning for more than 10 years, and believes it is the government and Spain's leading companies that need to push for this change. Productivity would increase, and civil society improve, he argues, because Spaniards don't have time to dedicate to local organisations, NGOs, and other charitable bodies. Family life would improve, too, as it would allow parents to spend more time with their children after work.

"We should be starting between 7.30am and 9am and never finishing work later than 6pm. Half an hour, or an hour, is more than enough to time to eat a healthy lunch, and not as so often happens here in Spain two hours, three hours," said Buqueras. "The siesta has to end! At most, you might need 10 or 12 minutes rest after lunch." And, anyway, most Spaniards don't have a nap after lunch, even if their working day permits them to take one, he said.

Another thing that needs to change is late-night prime-time TV, said Buqueras. "In England, the largest TV audience is at 7 or 8pm, but in Spain, it's 10pm. Because at 8pm in Spain, barely 50% of the population is at home, and you have to wait until 10pm to find that number of people at home, thus guaranteeing the viewing figures needed for prime time. Sometimes football matches don't kick off until 11pm!" he said.

All of this means people go to bed far later than they should and get less sleep than they need. Studies suggest Spaniards sleep an hour less than the rest of Europe, which means more accidents at work, less efficiency, and more children missing school. Additionally they work longer hours than their German and British counterparts, but are much less efficient.

But many believe it will take more than a change of the clock to bring Spain into line with the rest of Europe. Elver Christine Laanen, 24, is from the Netherlands but works at a healthcare company in Madrid. "I've had to get used to eating lunch at 1.30pm, when I would like to eat at 12pm. And now I make sure I don't eat a very big dinner, because I don't think it's that healthy to eat so much just before you go to bed."

She's not sure putting the clock back an hour would change much. "I think Spanish working hours are a cultural thing – you can't just say it's all because of the position of the sun."

Prof Chinchilla understands that "change is always hard, because people don't realise the damage they are doing to themselves with their traditions".

In the square, as Fernando finished his coffee and prepared to go back to the office, he agreed that a change of culture would not be easy. "We're Spaniards, and this is how we are. I'm not sure we'll like it if they impose these changes on us from above."