to close approximation, the question is one of your intensity and your duration, and it doesn't matter much whether you are going up hill or not.

Hills can be helpful to keep intervals safer and easier to complete without stoplights getting in the way though. Hills can also force you to go hard whereas on the flat you have to force yourself to go hard.

How many miles you go doesn't matter. How hard are you going, and for how much time. Since your tris are flat there will be some small secondary benefit from keeping most of your training on flat ground as the force/velocity patterns are a little different.

---

---

Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

The power that you're generating is the key. A hilly ride and a flat ride can have the same training effect but the difference is that you're probably more likely to ride at a higher intensity going uphill as you to some extent have no choice. On the flats it can be easy to just cruise along.

Some of my best training rides are on the trainer and it doesn't get flatter than that :)

---

Rodney
TrainingPeaks | Altra Running | RAD Roller
http://www.goinglong.ca

the issue with the hills is the downhills generally limit how hard you can pedal, so if you are OK with some sections where you are going easier, then fine. I like hills for things like v02 intervals where I can load myself up for 3 or 5 minutes and coast down, or sometimes I do short sprint on the grass up a hill on the cross bike. Hills are great for practicing your transition from climbing to going fast downhill, which can net you some free speed. Hills help you understand the difference between a power climb and a sit and spin climb, which is key to your pacing strategy in a shorter race. I see many triathletes climbing much too slowly when faced with a short hill, they climb everything like it's 20 minutes long.

A friend of mine does hill repeats at a local 500ft "mountain" that has an avg. grade of about 9degrees. He usually invites me and I decline. Personally, I don't know if there is a better benefit from these or not, I do intervals my own way using HR and open roads. I personally don't have the attention span to do 7-10 sets of 500ft climbs and rest on the descent. He loves it and it works for him. The big difference I see is he spends a lot of time out of the saddle and I don't. If I were training for super hilly road races I'd be more inclined to train that way. Since, I am not training for races like that I don't bother with the hill repeats. I do think he is a better climber than I am and there's probably a good reason why :)

---

"4 wheels move the body, 2 wheels move the soul"

I do hill repeats when I'm time crunched and don't want to stray too far from home*, but I do them on my TT bike on the aero bars. Often the cadence is lower than I would like, but it forces me to pedal at or above FTP so that I don't fall off, and it seems like a good workout because I breathe hard and my legs hurt afterwards. The hill I use takes me around 10 mins to ascend, and 3 or 4 mins to descend.

*was super useful a month or so ago, when my missus was close to full-term expecting our 2nd child, and I needed to be within 15 mins of home at all times!!**

**and couldn't be arsed with the turbo

I don't know if one is better but for me the hills add some variety. Long flat stretches can seem sort of like being on the trainer.

There's a little more to it than what I'd call the "powermeter" based responses that I've seen, but that's now all the story. The characteristics of how the source (rider) generates the power for the application needed (hill or flat/wind) plays a factor. When you stop pedaling on the flat, you slow down, but not as quickly as when you stop pedaling on a hill. It takes more torque to ride the hill vs. flat, though the watts output can be the same. The traits of the rider's power generation partly explains why there are climbers and time-trialers.

Practically applied - If you only ride flat courses, you don't have to worry about doing much hill work. But you would probably benefit from some training as a variation in training stimulus and the additional adaptation! If you decide to ride a hilly course, you need to add hill training to get exposure to the "torque" stimulus so you get some adaptation, because it will help you even if you aren't a good climber.

The question is even more interesting in running because the the passive force generation of the exercise.

I haven't done many hill repeats this year, but I tend to ride hilly courses as all my races have at least some hills, and some are quite hilly. I ride my elite crono fluid trainer a lot as well, and with no flywheel it feels an awful lot like pedalling up a false flat all day long. What I find when I get on the road is that I can easily hold FTP or a little higher while climbing, but it becomes a big challenge on a flat stretch of road. I have to look at my power output every few seconds because I always seem to start drifting below - it takes a lot of focus. I probably should ride more hard efforts on flat courses, but its just so convenient to crank out 2 x 20s on the trainer with no interruptions for stop signs, downhills etc.

Watts are watts. IT depends on what you want to get out of a workout. Hills are a nuisance for some training session not going up them, but going down you sometimes cannot hold the same wattage.

---

TrainingBible Coaching
http://www.trainingbible.com