Hignell is the son of a former Great Britain athlete.
Hignell was educated at Denstone College, a boarding independent school for boys (now co-educational), in the village of Denstone in Staffordshire in Central England, followed by Fitzwilliam College, University of Cambridge. Hignell won Blues at Cambridge in both cricket and rugby union, and when he graduated in 1977 he had already made several England appearances at full back. He was the second man to captain Cambridge at both cricket and rugby union.
Hignell made his England debut in 1975 in a brutal encounter with Australia in Brisbane - eight days later he was playing for Gloucestershire against Middlesex at Bristol and five weeks later he made 60 in the Varsity match.
After leaving university, he continued playing rugby for Bristol and England in the winter, while also working as a teacher (including at Bristol Cathedral School and Sherborne School), and cricket for Gloucestershire in the summer. As a right-handed batsman, he scored solidly rather than spectacularly, passing 1,000 runs in a season three times, including his final season in 1983, before his retirement. He won the last of his 14 England rugby caps in 1978-79.
Many references spell the given name 'Alister' or 'Alistair'.
Hignell continued to teach until he moved into journalism full-time and he became a respected reporter, as well as working extensively on BBC Radio. In 1999, he was diagnosed with multiple sclerosis and has since been an active fundraiser.
His final commentary for BBC Radio Five Live was the 2007-08 Guinness Premiership Final at Twickenham, where London Wasps beat Leicester Tigers 26–16. Retiring Wasps captain Lawrence Dallaglio dedicated the victory to Hignell. Later in 2008 he provided weekly rugby podcasts on the This is Bristol website.
Hignell won the BBC Sports Personality of the Year Helen Rollason Award in 2008 for his work in spreading awareness of multiple sclerosis.
Hignell was appointed Commander of the Order of the British Empire (CBE) in the 2009 Birthday Honours.
Hignell won the 'Best Rugby Book' category in the 2012 British Sports Book Awards for the book Higgy.
Alastair Hignell became Patron of Multiple Sclerosis UK (MS-UK) (formally Multiple Sclerosis Resource Centre) in 2002 and has since been active in raising funds for the charity. (More information can be found at www.ms-uk.org)
In 2008, inspired by Alastair's heroic achievements on and off the pitch, Higgy's Heroes, a fundraising body linked to MS-UK was created. Initially a one-off idea by a group of ex-teammates and opponents who decided to run the London Marathon in tribute to Higgy, the name and the idea continued beyond this one event. Since then there have been a number of Higgy's Heroes fundraising events largely based on physical achievements or sports activities. These include participants at the London Marathon and a regular large turn out in Alastair's home town for the yearly Stroud Half Marathon. Alastair moved to Brighton after living in Stroud for four years.