I'm not on any regimented training plan but I occasionally throw in some hill repeat riding on a street around the corner from my house. The thing is, the hill on this street is relatively short. It probably takes me somewhere in the neighborhood of 30 to 45 seconds to do it. Maybe 150 ft ascent. Basically, I just go up the hill, go down the hill, repeat, with no rest in between. Middle ring. Sometimes sitting, sometimes standing. Sometimes both. Last week I did it eight times. Am I wasting my time doing this? Do I need more reps? Do I need to find a longer climb to really see an impact? Your advice is appreciated.