Cragg's father was a coach in South Africa and now lives in Fayetteville, Arkansas with his wife. Alistair's older brother, Duncan, went to Southern Methodist University from 1994–99. Alistair followed him there in 1999. His first cross country season there, he was injured and finished the season poorly at the regional meet in Denton, Texas. Arkansas coach John McDonnell saw him after the race and said something about how he should not run if he was injured. The next spring, Alistair was the top freshman finisher in the 5000 m at the NCAA Championship meet, smashing SMU freshman records in that event.