World Indoors: Jessica Ennis looks for 'psychological boost'

Jessica Ennis says pentathlon victory at the World Indoor Championships in Istanbul would give her a "massive psychological boost" in Olympic year.

The 26-year-old Briton faces heptathlon world champion Tatyana Chernova and Olympic champion Natalya Dobrynska in the pentathlon on the opening day.

Chernova took Ennis's world title last year at Daegu but the Sheffield athlete has been in excellent form in 2012.

The 39-strong GB squad also features world 5,000m champion Mo Farah.

"It's going to be a massive psychological boost for anyone that does well here," said Ennis.

"I think, looking at everyone's performances and the way the athletes are performing around the world at the moment, they're on top form.

"To come away from this, whether it's a PB (personal best) or winning a medal, that's definitely going to give you a boost going forward for the rest of the year."

Russia's Ekaterina Bolshova has improved her pentathlon best by more than 500 points this year to a world leading 4,896, and is another threat in a strong pentathlon field.

Russian athlete Irina Belova set the world record of 4,991 points in 1992, with Ennis managing 4,937 when she won the indoor world title two years ago.

"I got quite close to it last time in Doha and it was something I'd not really thought of before," she said.

"Just judging from the shape I'm in and the shape the other girls are in, it's going to take a PB to obviously get it but I think it's something that any one of us could probably achieve.

"It's not something I'm focusing on but it would be a nice bonus."

Farah, who recently lost over two miles at the Aviva Grand Prix in Birmingham, goes in the 3,000m.

"I was a bit disappointed with the race," Farah told BBC Sport at the time. "I felt a bit heavy."

The long-distance athlete will look to make amends for Birmingham this weekend in Turkey, when he takes on Kenyan duo Augustine Choge and Edwin Soi, who are the only men to have broken 7 minutes 30 seconds this season.

Team GB sprinter Dwain Chambers, who is not allowed to particpate in the London Olympics later this year, is competing in the 60m sprint.

The world's fastest man, Usain Bolt, is not appearing in Istanbul and fellow Jamaican Asafa Powell failed to make the squad. Should either Lerone Clarke or Nesta Carter triumph, they will become the first sprinter from the island to win a 60m title. The final of the event is on Saturday.

Perri Shakes-Drayton, a 400m hurdles specialist, is one part of the Team GB women's 4x400m relay squad alongside Olympic 400m champion Christine Ohuruogu, Shana Cox, Nadine Okyere, Nicola Sanders and Laura Langowski. The final of the discipline takes place on Sunday.