Britain's Chris Froome arrives for the start of the sixth stage of the Tour de France. Photo: Peter Dejong/AP

Chris Froome admitted he'd had the jitters when an out-of-control parasol blew in front of the peloton during Thursday's Tour de France fourth stage.

Race leader and reigning champion Froome was one of several riders forced to swerve to avoid the parasol, as it rumbled across the road.

"It did just pop up from nowhere, there was a little gust of wind at that point so I think it blew over from one of the spectators on the side of the road," said Briton Froome, 32.

"It landed right in the middle of the road -- it's quite scary when that happens. One minute you're cruising along and the next there's a massive parasol in front of you and everyone's dodging to avoid it!"

For many observers, Thursday's 216km flat stage from Vesoul to Troyes was dull.

A three-man breakaway that was doomed from the start took off inside the first kilometre but was never allowed to get even four minutes up the road.

The sprinters' teams controlled the tempo of the peloton and easily caught the break, although not until 3km from the finish.

But Froome said he'd enjoyed the day in scorching temperatures.

"I'm not complaining, I actually quite enjoy these long days, being a bit more relaxed and getting to chat a little more in the peloton and speak to guys you don't normally speak to," he said.

"You get to take in the scenery a bit more. The atmosphere on the roads has been great and the French public has been great."

The true battle for the yellow jersey will take place in the mountains, like Wednesday's first summit finish to La Planche des Belles Filles, won by Italian Fabio Aru but in which Froome finished third and took the leader's jersey off his Sky team-mate Geraint Thomas.

Briton Simon Yates, who holds the young rider's white jersey and sits sixth overall, 43sec behind Froome, concurred with his compatriot.

"Yeah, there wasn't a lot to do," he said.

For another overall contender, Colombia's Nairo Quintana, these long flat stages are all about just getting to the finish line.

"These stages are about survival. Everyone who gets through them without crashing is a winner!"

Aru, like Froome, said he enjoyed the searing heat with temperatures into the mid 30s Celsius and much hotter still on the road.

"I feel good, it was a very long day, very hot," said the Sardinian, who currently holds the king of the mountains polkadot jersey and is third overall at just 14sec.

"It's always very hot in Sardinia, here it was also very hot, so I'm used to it."

Two-time former winner Alberto Contador, one place above Quintana in eighth, said he felt there should be a limit to stage length.

"The objective is to avoid crashes and to hydrate well because it is very hot," the Spanish veteran said.

"Today it was almost 230km with the neutralised section (before the official start), I think they are more kilometres than necessary -- 200km could be good as a limit."

Froome, though, disagreed.

"Personally I think they're part of Grand Tours, I've got no issue with them," he said.