Training objective: a very hard 2 hour ride on very hilly terrain with some hard efforts on the hills with the cadence between 65-75 rpm's and the heart rate at 155 bpm's Phew - a hot one today with the sweat coming off in buckets. I ran out of liquid at about the 1 hour 20 minute mark. Crazy potholes from about Friemersheim all the way to Charles Road at the turn to Great Brak/Blanco/Jonkersberg - which is about 1/3 the whole ride. Chain came off twice as I bumped along on two downhill sections, despite the clutch being engaged (managed to get it back on on the fly by clicking the front derailleur). Very taxing when combined with wind against. Had a hard time keeping the heart rate up in that mess - it was a frustrating mental challenge as much as physical. Rest day tomorrow and boy do I need it - phew!