Running

I trained for inter-lab Ekiden-race last night. It’s after an interval of one year to long-distance running. However, a mere 2 km running has tired me. The running course is an uneven land, especially last half; it’s precipitous road.
Even so, I was utterly fatigued. Hmm, am I getting old? I hate to admit it. Anyway I should train over and over and over!