In her youth, as Margaret Jackson, she represented both Tasmania and Victoria in track and field athletics and netball.

In 2000, together with Sharelle McMahon, Wilma Shakespear, Joyce Brown, Shelley O'Donnell and Simone McKinnis, Caldow was named in Netball Victoria's Team of the Century.

[10][11] Between 1991 and 1995, Caldow served as head netball coach at the Victorian Institute of Sport, mentoring among others, Sharelle McMahon.

[3][18][19][20] Between 2002 and 2003, Caldow served as head coach of Melbourne Kestrels in the Commonwealth Bank Trophy league.

[22][23][24][25][26] Caldow was credited with mentoring Louisa Brownfield, Joanne Harten, Rachel Dunn and Pamela Cookey.

During this time, she was a member of Australia's coaching team at the 2015 Netball World Cup and at the 2014 and 2018 Commonwealth Games.