Pepper began swimming at the age of four, as his parents were concerned about the canal that backed onto their home and wanted him to be able to swim. From practising in his local pool in Stockport he was spotted by the local swimming club and was invited to join. As Pepper has a learning disability similar to a dyslexia he was given an S14 parasport classification. His disability effects his ability to both retaining instruction and his co-ordination. Pepper had hopes that the times he was recording would make him eligible for the British team at the 2004 Summer Paralympics in Athens, but after the basketball controversy at the 2000 Games, his classification was dropped from all events by the International Paralympic Committee. Pepper's initial reaction was one of anger and he decided to quit the sport, but a month later his coach persuaded him to return to training. In 2009 the IPC decided to lift the ban on S14 entrants and Pepper was able to enter his first major international event, the 2009 IPC Swimming European Championships in Reykjavik, Iceland. There he entered three events, the 100m freestyle, 100m breaststroke and the 200m individual medley, taking gold in all three. The following year Pepper travelled to Eindhoven to represent Britain at the 2010 IPC Swimming World Championships entering two events. In the 100m breaststroke he recorded a time of 1:11.08 to take gold, a feat he repeated in the 200m freestyle making him a double world champion. He followed this in 2011 with his second European Championship, this time in Berlin. He failed to defend his 100m breaststroke, coming second to take silver, but victory in the 200m Freestyle gave him his fourth European Championship gold. With the coming of the 2012 Summer Paralympics it was announced that several S14 events would be included in the swimming schedule for the first time. Pepper was part of the Great Britain team and was selected for two events, the 200m freestyle and the 100m breaststroke. Pepper swam in heat 1 of the 200m freestyle. As it was the inaugural race of this event under the S14 classification, by coming first with a time of 2:01.94, Pepper, by default, became the Paralympic champion. His reign was short lived as his time was beaten by Iceland's Jon Margeir Sverrisson in the very next heat. In the final Pepper was unable to improve on his first round heat time and finished seventh. In the breaststroke he was again placed in the first heat. Pepper finished third in a race which saw Russia's Artem Pavlenko set a new World record. As one of the slowest qualifiers, Pepper was placed in the unfavorable first lane and again finished seventh. In 2013 Pepper returned to represent Great Britain, travelling to Montreal to compete in the 2013 IPC Swimming World Championships. He swam in two events taking the silver in 200m individual medley.
