He set a new world record for 30,000 m of 1 h 34 min 01.8 s in 1964. In that race he also set world records for 20 miles (1 h 40 min 58.0 s) and 2 hours (37,994m). The IAAF did not recognise the latter two marks for world records, but they were accepted as United Kingdom national records.[5]
At the 1968 Olympic Games, in Mexico City, his height was recorded at 5 ft 8 in (172 cm) and his weight was 141 lb (64 kg).[1]
Alder ran his last marathon in the 1970 Commonwealth Games in Edinburgh. In September 1970, in London, he set a new record for 30,000 m of 1 h 31 min 30.4 s which still stands today.[6][7]
He won The Great Northern Half Marathon, Belfast in 1971 promoted by County Antrim Harriers in a time of 1:05:05.(Athletics Weekly 22 May 1971)