Coast but Not Too Much
The downhills can be a bit of a down period, but you have to concentrate. There are technical aspects and you can lose a lot of time. Most people take their foot off the gas when they get to the top of a climb. You start to drift back and all of a sudden, you're way behind. You have to be cautious, but you have to recover when you can. I try to give an extra 10-second surge at the end of the hill to make sure I'm in a good position for the descent. Pretend the summit is another 500 meters ahead and then take your foot off the pedal.