The American coach of Olympic champion Mo Farah may have broken anti-doping rules to boost the performance of some of his athletes, says a leaked report.
Three Russian athletes given clearance to compete internationally under a neutral flag by athletics' world governing body the IAAF.
Laura Muir will attempt to win 1500m and 3,000m gold at the European Indoor Championships in Serbia in March as GB announces its team.
Budapest stands "no chance" of hosting the 2024 Olympics, according to the bid's chief organiser.
Audio & Video
Mo Farah bows out of his indoor athletics career by breaking the European 5,000m record in Birmingham.
Steve Cram explains how some of Britain's best athletes are preparing for the 2017 season with altitude training in South Africa.
How to get into Athletics
How to get into athletics - one of the widest ranges of choice in sport, from jumps and throws to sprints or distance running.
What's on BBC Sport this week
This week's sport on the BBC includes the Six Nations, Super League, skeleton and boxing, plus the Premier League and EFL Cup.