In May 2008, Robertson was fitted with an artificial pacemaker to treat 'complete heart block' and then in January 2010, he underwent a second operation to insert the pacemaker deeper. In February 2014, he underwent brain surgery, and was required to have a craniotomy when a CT scan picked up a large cyst in his brain - originally diagnosed as a tumour.

In January 2016, he became the youngest Brit and the first Scot to ski solo, unsupported and unassisted to the South Pole in Antarctica. He set off from Hercules Inlet on the edge of Antarctica on 5 December 2015 and arrived at the Geographic South Pole on 13 January 2016, completing expedition 'Due South 2015'.

He has been on winter expeditions to central Norway, Eastern Greenland, as well as Antarctica, and in 2016 he successfully completed the inaugural Cape Wrath Ultra marathon. The race from Fort william to Cape Wrath took place over 8 days and covered a distance of 250 miles (400 km+). The winner of the ladies race, Emanuela Marzotto, from Italy said: "This race is the hardest thing I’ve done, harder than the 10 day race in Australia or the Marathon Des Sables.". Among other events, he has also competed in the Lake District Ten Peaks Ultra, the Big Ben Nevis Triathlon in Fort william and the Wimbleball 70.3 Iron Man.