I have been using Trainerroad since February 2026 and have added 55 watts to my initial AI FTP detection through 90% indoor workouts. My workouts are appropriately hard and I have been enjoying indoor workouts. I am transitioning out of just pure FTP build into getting ready for a race in June by adding in more endurance days. I want to be doing as many of these outside but have a ran into a few issues:
Finding locations to hold consistent power. Anyone have any recommendations for spots in the Denver Area Front Range? I just did a workout at Rocky Mountain Arsenal, there are some longer sections there but my average drops when having to navigate the single track sections, going through gates and going like 25 mph on flats or descents or navigating around people trying to keep my power up.
I was somewhat successful at shifting on hills and slowing way down but I still spent 30% in tempo as the workout target was top of Zone 2 and 8% in threshold somehow. Would it be better to barely hit my power targets? Does anyone know how this impacts the training effect? At least my Heart Rate stayed in zone 2 the whole time.
My recommendation would be to just do the workouts you want/need to indoors, and then just enjoy yourself when you go outside. This is my personal bent, as I find trying to do the workout structure outside, due to the variables (terrain, traffic, stop signs/signals, etc.). If you do want to actually do a workout outside, though, maybe try to find an alternate workout that seems like it will (reasonably) match the terrain you want to ride.
Perhaps counter to what most people think, and as a city dweller where nothing is flat, I find endurance easiest to do indoor. Holding a constant power for 1,2,3,4 even 5hrs on the trainer. Worth it at least once per week.
Even more so for sustained tempo or sweet spot.
For intervals I look for a steady gradient, a hill with no traffic lights and do repeats. Searching the best cycling hills for an area usually finds these.
For easy rides - different to endurance imho - riding outside alone and not worrying about the power works best, basically never pushing so the heart rate never gets up and even sweet spot is a distant thing on the horizon.
I’ve definitely ridden my brakes when outside trying to time a light and keep endurance power, it’s pretty silly but I’m guilty of it. It’s a necessary technique at times when running out of road or sometimes the interval ends a little early or gets interrupted. As for endurance rides, it can be tricky when you are off road. I might ride the brakes a when navigating traffic on the trail or just ride normally and then proceed. I think on undulating terrain you have to handle the bike and terrain and revert to RPE. You’ll get some power drops and spikes, but it goes with the terrain, no pun intended. If I really want to nail my workouts then I’m on the trainer or have a proven course that I can use. Sorry, I’m not from your area so I can’t suggest anywhere. But, after moving around a bit I know you can figure things out by looking at routes on strava, ridewithgps. Good luck with the training.
Not sure where you’re based, but in Boulder, I’ve found the area between the Boulder Reservoir and Hygiene pretty workable. Lots of roads where bikes are common. You just have to plan around when you hit start on the workout and whether or not you want to hit climbs. Lots of dirt and gravel in the area too.
I do like that area, the whole old man winter race area is good. Thanks for the reminder! I am in the Central Denver area so that is still a bit of a drive on a weekday.
Cherry Creek Reservoir and Chatfield are both really good for intervals, also very popular cycling spots.
I do all of my intervals outside and find it more enjoyable and easier mentally than on the trainer and it also better applies to actual racing, outside.
I lived up in the mountains and worked in Golden for 20 years before moving to Alaska. Back then, I did all my workouts outdoors. Lookout Mountain is a great place for intervals, long or short. Dinosaur ridge or Red Rocks parks have good hills for vo2 max. Long endurance is easy with so many miles of multi-use paths to connect around the city. With a bit of creativity, nice weather, and nearly unlimited cycling opportunities, it’s a great place to train. Enjoy!
If you are already going out and doing Rocky Mountain Arsenal, I use the dirt road East of there, nearish to the airport, for a lot of sweet spot and endurance work. Very little to no traffic and straight roads. Lots of options.
I like long uninterrupted gradual grades for outdoor workouts. I believe there are some good canyons up into the foothills. Deer Creek Canyon up to Pleasant Park comes to mind. It’s popular with cyclists in general. Golden Gate Canyon is another. Waterton Canyon (very wide smooth dirt/gravel no cars) is OK but short so turn around for recovery intervals. Also can do loops around Chatfield (some road bike rideable gravel at the top of the dam) or Cherry Creek reservoirs.
That is great! Thank you for sharing those routes! I am just now getting into the 3 hour endurance rides, this will be perfect and not too far from home!
I do my interval work inside, but I’ve done long endurance rides on the High Line Canal Trail starting just north of the gravel section that begins in Cherry Hills Village. Depending on where you live in Denver, if you need to drive there, there’s parking right at the start of the gravel section. You can ride High Line all the way down to Chatfield, so you can definitely put in longer rides, and the trail is wide enough that passing while maintaining power is usually doable.