Holland's Marianne Vos increased her overall lead of the Friends Life Women's Tour by winning a second consecutive stage on what proved an emotional day for the Trott sisters.

Britain's Olympic silver-medallist Lizzie Armitstead from Otley - tenth in stage four, which she required a wheel change towards the end of - is fourth, 30 seconds behind Vos.

Rabo-Liv rider Vos crossed the line today ahead of Italy's Giorgia Bronzini (Wiggle-Honda) in second and Leicester's Lucy Garner (Great Britain) in third.

The event's fourth stage, running from Cheshunt to Welwyn Garden City, also saw local girl Laura Trott (Wiggle-Honda) manage to compete the day after suffering a heavy crash, while her sister Emma (Boels-Dolmans) announced on the finish line she will retire after tomorrow's final stage.

Twenty-two-year-old double Olympic track champion Laura, who had to go to hospital for precautionary scans after her crash on Friday, came 29th.

Emma, two years older, crossed the line in tears as she came 58th.

And she said afterwards: "I've not said anything until now, but I'm retiring after this race, so today means a lot more to me.

"I started thinking it at the end of last year. I love cycling, and that's the problem. I signed a deal with the team anyway, and sometimes when you've had a break you can come back mentally.

"I was in New Zealand with my partner, and I didn't really want to come back.

"Then I lost two dear friends of mine, and that changed my perspective on life. I went on training camp, and I didn't want to be there, I wanted to get home so badly.

"I raced, and the feelings weren't the same as they were five years ago. I've been a pro for seven years, I've raced for 14, and I've enjoyed it. I have no regrets."

World and Olympic champion Vos is 19 seconds clear in the overall classification of second-placed Emma Johansson (Orica AIS) of Sweden, who came fourth in stage four.

Italy's Rossella Ratto (Estado de Mexico Faren) is a further three seconds back in third.

Tomorrow's race finish is in Bury St Edmunds.