Matthew Hudson-Smith is a British track and field sprinter who specialises in the 400 metres. He holds, as of August 2023, the British and European record, running a personal best of 44.26 seconds for the distance set at the Budapest World Championships in 2023. He was the 2018 European Champion in 400 metres, and a member of the gold-winning teams in the 4 x 400 metre relay at the 2014 European Athletics Championships, with Great Britain and 2014 Commonwealth Games with England.

The 400 metres, or 400-meter dash, is a sprint event in track and field competitions. It has been featured in the athletics programme at the Summer Olympics since 1896 for men and since 1964 for women. On a standard outdoor running track, it is one lap around the track. Runners start in staggered positions and race in separate lanes for the entire course. In many countries, athletes previously competed in the 440-yard dash (402.336 m)—which is a quarter of a mile and was referred to as the "quarter-mile"—instead of the 400 m (437.445 yards), though this distance is now obsolete.