The point of the break is to let your attention recover, so choose something that actually rests it. Stand up, stretch, get water, look out of a window, walk around. Physical, low-stimulation activities reset your focus far better than switching from work to a feed.
Avoid checking social media or news in the break. It feels like a rest but it floods your attention with new inputs, and the residue follows you back into the next interval, so you start it already half-distracted.