80 minute run up in the Los Altos Hills with Dimitri. Warm and humid. We took the HP Trail for the first time today. It was a nice alternative. I walk-ran much of the steeper uphill sections but my HR stayed up in the zone so I was getting a decent training effect.The humidity definitely had an effect on my heart rate especially over the last mile. I had to slow down to stay at 70%. I felt fine otherwise.