Today's run: 2.5 km (1.55 miles) in 19(ish) minutes.
Injury check: Knee.
Today I tried a different kind of interval training: run for 1 km (~7 mins) then walk until the next audio cue on my app (9 mins) and then run another 1 km, and repeat.
I managed the first 1k, the walk, and then another 1.5k - and then The Knee struck. A minor stab of pain - which, with my knee, isn't actually beyond expectation - so I stopped to stretch out. It felt ok so I tried again and made it another 100m before it tweaked again.
So that was that.