PHOTOS: Gold medal winners on Day 15 of the Games

Dubbed "Usain Bolt on water", Britain's Ed McKeever powered to victory in the men's K1 200 in front of thousands of screaming fans on Saturday to take the first gold awarded in the new shorter and more explosive Olympic distance.

McKeever, a trainee accountant from the southwestern English town of Bradford on Avon, said that having won gold he was now more willing to accept the nickname given to him by the British media.

"Luckily I've got the gold medal to go with it," the unassuming winner told reporters on the side of the lake. "I'm more willing of that tagline.

"After the start, I was kind of out clean and I just held on. My main emotion was probably relief."

The sprint over 200 meters and lasting around 36 seconds is designed to increase interest in the sport, with the canoeists taking around three strokes per second in a fast and dramatic fight for the line.

McKeever, who had started the race as a favorite after emerging from the heats as the fastest qualifier, powered off the start in blustery head-wind conditions to take a lead over the rest of the field.

He punched the air as he crossed the line around 0.25 seconds ahead and ran his hands through the water, before waving to the grandstands.

Spain's Saul Craviotto Rivero took the silver and Canada's Mark de Jonge the bronze.

Russia's Yury Postrigay and Alexander Dyachenko blew away the field to take victory in the men's C2 200 canoeing in a thrilling sprint for the line before roaring crowds in the inaugural final at the Olympics on Saturday.

Raman Piatrushenka and Vadzim Makhneu of Belarus took silver and Britain's Liam Heath and Jon Schofield the bronze.

The sprint over 200 meters is new to the Olympic program and is designed to increase interest in the sport, with the canoeists taking three strokes per second in an explosive fight for the line.

The Russian pair had a good start but powered away from the field in the middle 100 meters in the most comprehensive victory of the day's racing on Dorney Lake. They thrust their paddles in the air as they crossed the line and roared with delight.

New Zealand's Lisa Carrington stormed through the field to take victory in the inaugural K1 200 on Dorney Lake on Saturday to add to her world championship title and give her country its first women's Olympic gold medal in sprint canoeing.

The result consigned Hungarian great Natasa Douchev-Janics to a bronze medal after she won a silver earlier in the week. She had been in the hunt for her fourth Olympic gold medal overall.

The explosive sprint over 200 meters is new to the Olympic program and designed to increase interest in the sport, with the canoeists taking three strokes per second in an explosive fight for the line.

Ukraine's Inna Osypenko-Radomska, Olympic champion from 2008 over the 500-metre distance and silver medalist from earlier this week, took another silver.

France's Julie Bresset won the gold medal in the women's mountain bike event at the Olympics on Saturday.

German Sabine Spitz took silver and Georgia Gould of the United States claimed the bronze.

Russia's Sergey Kirdyapkin won gold in the men's 50km race walk at the London Games on Saturday in an Olympic record time of three hours 35 minutes 59 seconds.

The 32-year-old double world champion shaved more than a second off Alex Schwazer's record of 3:37:09 to finish 54 seconds ahead of Australia's Jared Tallent, whose time was also inside the previous Olympic record and a personal best.

China's Si Tianfeng won bronze in a personal best of 3:37:16, adding to Chen Ding's 20km gold and Wang Zhen's bronze a week ago - China's first men's race walk medals.

The Russian trio of Kirdyapkin, Igor Erokhin and last year's world champion Sergey Bakulin were strong medal favourites after Italy's defending champion Schwazer was excluded from the London Games on Monday for testing positive for EPO.