Using PC while backing up

Hello. I am using True Image 2013. Going back probably 20 years or so I remember being told that when I was backing up to my company's server I should not be carrying out other tasks on my computer at the same time. When I am backing up using True Image is it safer to avoid doing anything else at the same time on the PC?

My computer is reasonably well specified:-

3rd Generation Intel® Core™ i7-3770 processor (3.40GHz, 8MB of L3 Cache)

16GB2 Dual Channel DDR3 SDRAM at 1600MHz

Crucial 256GB M4 Serial ATA 6Gb/s SSD 2.5” (bar code: X0004KOCCV)

2 x 2TB 7200 RPM Serial ATA Hard Drives

Thanks for your comments. J.