11:05Hey You What If?Series 1You Could Run at the Speed of Sound?CBBC Thu 15th Jul 2021, 11:05 on CBBC ChannelAvailable for 8 monthsA fun run goes wrong when one ambitious runner tries going at the speed of sound.GenresChildren'sFactualFactualScience & NatureBrandHey You What If?SeriesHey You What If?: Series 1 Source: BBC Online