Now 21, McDonald has performed consistently well in triathlons over the years and showed much early promise. She started racing at the age of eight, and in 2012 competed in no less than 14 events, coming first in five of them. In 2014, as a competitor in the junior women category, McDonald won the London Triathlon in a time of 1 hour, 11 minutes and 40 seconds, came third in the European Junior Triathlon in Nottingham and seventh in the European Junior Triathlon France in Vierzon.

After moving into the elite women category, she completed the 2016 GBR Sprint Triathlon National Championships in Liverpool in 1 hour, 4 minutes and 46 seconds, coming 14th, and a year later was placed 24th in the Holten ETU Sprint Triathlon Premium European Cup in the Netherlands.

More recently, McDonald qualified to represent Great Britain in the 2019 Pontevedra ITU Cross Triathlon World Championships on 30 April in northwest Spain. She came ninth after competing against the best under-23s in the world, and 23rd in the elite women category. The event comprises a 1 km swim, 30 km off-road cycling on a mountain bike, and a 7 km run, also off-road.

Known by the nickname ‘Mini Mac’, McDonald hails from Leamington Spa but lives in Loughborough, where she works as a part-time swimming teacher and trains with the Loughborough Development Squad.