Flat Pedals for Indoor Training Only

I’ve made great progress on the indoor erg trainer, but it is slowly creating more knee pain on the right side. Note, this is 99% only while riding indoors. Outside is a non-issue, but with my schedule, almost all of my time is spent riding indoors.

I grew up playing hockey and only ever stopping on one side, so my right leg is weaker, lacks balance, and shoes even fit differently. While my left leg & foot feel like a powerful train riding the rails, my right side always feels like its trying to catch up/not hurt.

I’ve spent a lot of energy and money playing with fit professionally & by myself including shoes, shims (in & out of shoe), float, cleat position, and socks. I believe I have 4 troubleshooting steps left…

  1. Work with a medical sports professional to receive custom orthotics along with a new professional fit.
  2. Switch to flat pedals… sure it’s not ideal, but neither is staying off the bike
  3. Build/buy a rocker plate or Neo/KK trainer that has some sway
  4. Dedicate even more time on single leg strength and balance.

I like #2 the best, because it requires the least amount of money, time, and commitment… flats for indoor use only… is it really that bad?

If the purpose is to train the way you ride outdoors, yes, it is that bad. You will train 1/4th of your pedal stroke and miss a whole bunch of muscles that get used in your actual outdoor pedal stroke.


Like @kurt.braeckel mentioned, with clip-in style pedals you get to practice all four pedalling quadrants when following Coach Chad’s drills. With flat pedals, it’s pretty hard to get more than just the simple push down, though you can refine your pedal stroke to include a bit of the kick/pull motion.

I know it might be more work and more expensive, but your option #1 seems to make the most sense. I’m a firm believer that you shouldn’t skimp on anything that affects your health. However, if after working with a professional, you believe that the static position on a trainer is causing your indoor woes, perhaps a rocker plate could be a good idea. Lastly, if your muscle imbalance is really so significant, option #4 is going to be crucial. I’m not a sports physio, but from what I’ve heard, you want your body to be pretty even/symmetrical or you’ll cause issues and pain. Best of luck!


You might also consider getting power meter pedals that can show you left/right balance.

I got a new left knee a couple years ago. I definitely have leg strength imbalances. Mine showed up as hip/glute soreness as well as right knee soreness. Like the OP this happened only on indoor trainer rides, outside I don’t notice any issues. When I got the pedals the amazing thing was it showed my left leg (with the new knee) was stronger than the right. It was 57% Left to 43% Right when I first started.

I am working with a trainer to strengthen and stretch my leg muscles. This is definitely helping restore the balance. I also found that doing aerobic endurance workouts allowed me to work on left/right balance issues as well as general leg strengthening. I can concentrate on one leg at a time and do one leg drills (with both legs clipped in).

I would go with 1 and 4 combined!

I noticed that you don’t have stretching or activation on your list. In my experience the indoor trainer related comfort and fit issues are related to lack of movement, i.e. rocker plate; but also lack of stretching the effected muscle groups. I’d recommend a good stretching and activation program first before paying a bunch of money on fit related issues.

I have some of the same problems related to hip tightness beginning to radiate as knee pain and it really comes down to a lack of flexibility which is made worse from sitting at a desk all day and then riding a trainer that is in a fixed position.

Might help.

Don’t be scared of flat pedals! You can come much closer (if not exactly) to recreating your “clipped” pedal stroke on flats. This is especially true if you use MTB style pedals with metal pins and rubber shoes. See this GCN video where there is no significant difference in physiological markers between flats and clipped, and this is using road shoes without cleats on cheap pedals.

For background, I road rode recreationally, clipped in, race CX pretty seriously clipped in, and MTB recreationally, always on flat pedals, and commute, 50/50 flats and clipped in. I have used both flats and clips on the trainer. Unless I move my foot position drastically on flats, I notice no difference in my pedal stroke between flats and clipless pedals.
In my opinion, I think the real benefits to clipping in are:

  • Ability to keep the power down on bumpy terrain, think a CX race
  • keeping attached to pedals during very high speed, high power efforts like sprints
  • A consistent position (some may argue this is also a con)

I am a triathlete who had a serious achilles tendon injury.
The run was to blame but the bike was not totally neutral since it made things worse anytime I tried to get back.
I decided to change to flat pedals both indoors and outdoors as a way to moderate the tendon strain and it worked really well.
The power was in line with the past for sustainable efforts and I can say that I even felt better while climbing.
However, sprinting was disastrous and the best I could do was around 800w when my max is 1200w.
After a couple of months I went back to my regular Look Keo but moved the cleats to the far back trying to support my pedaling closer to mid foot which is supposed to reduce calf and achilles tension.
It worked very well but I had to lower the saddle a bit. I had a few episodes of knee pain in the past and I never ever felt it again. It seems that this extreme cleat position is a little more friendly to the joints.
The only issue is sprinting. My position became too much forward and max power and bike control were
seriously affected.