fartlek 23:04 [4] 5.42 km (4:15 / km) +8m 4:13 / km
shoes: kayano 26
It all started quite well and then the session got very uncomfortable all of a sudden. I stopped. Then when I tried to get going again I had what felt like so much lactate in my muscles I was straining myself hugely to move even around 5 min/k pace.