Antonina Yefremova (born 19 July 1981) is a Ukrainian

Ukraine

Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...

 sprinter who specializes in the 400 metres

400 metres

The 400 metres, or 400 metre dash, is a common sprinting event in track and field competitions. It has been featured in the athletics programme at the Summer Olympics since 1896 . On a standard outdoor running track, it is exactly one lap around the track. Runners start in staggered positions and...

.

She won the gold medal at the 2001 European U23 Championships

2001 European Athletics U23 Championships

The 2001 European Athletics U23 Championships is the 2001 version of the European Athletics U23 Championships. It was held in the Dutch city of Amsterdam.-Men's Results:-Women's Results:-Medals table:- References :*...

, finished sixth at the 2002 European Championships

2002 European Championships in Athletics

The 18th European Athletics Championships were held from 6 August to 11 August 2002 in the Olympic Stadium of Munich, Germany.-Track:1994 |1998 |2002 |2006 |2010 |...

 and fourth at the 2008 World Indoor Championships. She reached the semi-final at the 2000 World Junior Championships

2000 World Junior Championships in Athletics

The 2000 World Junior Championships in Athletics is the 2000 version of the World Junior Championships in Athletics. It was held in Santiago, Chile.-Men:-Women:-Medals table:...

, the 2003 World Championships

2003 World Championships in Athletics – Women's 400 metres

These are the official results of the Women's 400 metres event at the 2003 IAAF World Championships in Paris, France. There were a total number of 37 participating athletes, with five qualifying heats, three semi-finals and the final held on Wednesday 27 August 2003 at...

 and the 2004 Olympic Games, and competed at the 2003 World Indoor Championships

2003 IAAF World Indoor Championships

The 9th IAAF World Indoor Championships in Athletics were held in the National Indoor Arena in Birmingham, UK from 14 March to 16 March 2003. It was the first time the Championships had been held in the UK...

, the 2005 World Championships

2005 World Championships in Athletics – Women's 400 metres

The women's 200 metres at the 2005 World Championships in Athletics was held on August 7, 8 and 10 at the Helsinki Olympic Stadium.-Medals:-Results:All times shown are in seconds.-Heat 1:# Ana Guevara 51.14 Q# Christine Amertil 51.35 Q...

, the 2008 Olympic Games and the 2010 World Indoor Championships

2010 IAAF World Indoor Championships – Women's 400 metres

The women's 400 metres at the 2010 IAAF World Indoor Championships was held at the ASPIRE Dome on 12 and 13 March.-Medalists:-Records:-Qualification standards:-Schedule:-Heats:...

 without progressing from the first round.

In the 4 x 400 metres relay

4 x 400 metres relay

The 4 x 400 meters relay or long relay is an athletics track event in which teams comprise four runners who each complete 400 meters or one lap. It is traditionally the final event of a track meet. At top class events, the first 500 meters is run in lanes...

 she finished fifth at the 2002 World Cup

2002 IAAF World Cup

The 9th IAAF World Cup in Athletics was an international track and field sporting event sponsored by the International Association of Athletics Federations. It was hosted by Madrid, September 21–22, 2002, in the Estadio La Peineta...

, fifth at the 2003 World Indoor Championships

2003 IAAF World Indoor Championships

The 9th IAAF World Indoor Championships in Athletics were held in the National Indoor Arena in Birmingham, UK from 14 March to 16 March 2003. It was the first time the Championships had been held in the UK...

, fourth at the 2005 European Indoor Championships, fifth at the 2005 World Championships, won a bronze medal at the 2005 Summer Universiade

Athletics at the 2005 Summer Universiade

The athletics competition in the 2005 Summer Universiade was held on the İzmir Atatürk Stadyumu in İzmir, Turkey, between 15 August and 20 August 2005.-Men's events:-Women's events:-Medal table:-References:* - GBR Athletics* - GBR Athletics* - FIBU...

, and won a gold medal at the 2007 Summer Universiade

Athletics at the 2007 Summer Universiade

The athletics competition at the 2007 Summer Universiade was held in the Main Stadium at Thammasat University in Bangkok, Thailand, between 9 August and 14 August 2007.-Men's events:-Women's events:-Medals table:-Results:******...

. She also competed at the 2003 World Championships

2003 World Championships in Athletics – Women's 4 x 400 metres relay

These are the official results of the Women's 4x400 metres event at the 2003 IAAF World Championships in Paris, France. Their final was held on Sunday 31 August 2001 at 19:10h.-Final:-Heat 1:-Heat 2:-Heat 3:-References:*...

, the 2004 Olympic Games, the 2007 World Championships

2007 World Championships in Athletics – Women's 4 x 400 metres relay

The women's 4 x 400 metres relay at the 2007 World Championships in Athletics was held at the Nagai Stadium on 1 and 2 September.-Medalists:* Runners who participated in the heats only and received medals.-Schedule:-Heats:...

, and the 2009 World Championships

2009 World Championships in Athletics – Women's 4 x 400 metres relay

The women's 4 x 400 metres relay at the 2009 World Championships in Athletics was held at the Olympic Stadium on August 22 and August 23.-Medalists:* Runners who participated in the heats only and received medals.-Records:...

.

Her personal best times are 50.70 seconds in the 400 metres, achieved in June 2002 in Annecy

Annecy

Annecy is a commune in the Haute-Savoie department in the Rhône-Alpes region in south-eastern France.It lies on the northern tip of Lake Annecy , 35 kilometres south of Geneva.-Administration:...

, and 24.35 in the 200 metres (indoor), achieved in February 2005 in Sumy

Sumy

* 1897 - 70.53% Ukrainians, 24.1% Russians, 2.6% Jewish, 2.67% others* 1926 - 80.7% Ukrainians, 11.8% Russians, 5.5% Jewish, 2% others* 1959 - 79% Ukrainians, 20% Russians, 1% others...

.