Noticed that when I do my Trainer Road program outside, my knees are great however I’m finding that when doing them inside I find the intensity harder and my knees hurt. Pain is right in the middle to lower area of the patella. Should I be reducing the intensity to 85-90% of the prescribed workout effort when indoors?
No.
Also, need more info. Is the bike and fit exactly the same?
Professional bike fitting was done 5 years ago and since I’ve been on Trainer Road (3-4 months) I get knee pain only when doing the higher intensity workouts.
Any difference in cadence between inside and outside?
Perhaps you need to look at you cleat position. Maybe under the resistance of the trainer you are noticing now what has always been a problem. I found this guide useful but when bike fits lowered my saddle I’ve been less sensitive to cleat angle just the general toe in/out.
Yup…harder to push thus lower RPM.
Can’t get the numbers doing higher RPMs…not in my skillset and will never be. I generally average 85-90 RPMs.
5 years ago is a while at this point – our bodies can change a lot over that time, so it may be worth considering getting another bike fit done.
Scheduling an appointment with a PT or a doctor could be a good call if that’s possible as well.
Additionally, we have a big thread on knee pain here if you’re interested.
How is your warm up prior to getting on the bike? I was experiencing the exact same thing and told my buddy about it who is a physical therapist and he gave me a 10 minute warmup routine to follow before I got on the bike and it stopped my pain immediately. I’m not sure about indoor versus outdoor. All I could figure was the the fact that the bike is more rigid on the trainer.
Someone mentions that I should take my Wahoo out of ERG mode.
Comments?
Maybe, but it likely depends on more factors. What bike gearing (chainring size and rear cog size) are you using on the trainer?
Seems you may be adopting a lower cadence inside (if I read that comment above correctly), which will apply a higher force to your legs at the same power level outside with your higher cadence. This alone can be a reason for higher strain leading to soreness or injury.
I ask about gearing since this relates to the functional flywheel speed of the trainer. Many people prefer higher gearing (ex: 50t x 11t) since it spins the flywheel much faster and feels closer to outside loads. That is compared to lower gearing (ex: 34t x 17t) that I use to simulate lower inertia riding like gravel and MTB.
There are various reasons to use high, medium or low gearing for the trainer, but I have seen reports similar to yours for people running lower gear and slower flywheel speed, especially compared to their style used outside.
I concur that higher RPM’s = less strain on the knees.
Maybe a high RPM (Spin) warmup will help with getting my knees ready for what’s ahead.
Cheers
Maybe, but again the cadence is only one part of the system. Your gearing may have an impact here and should be considered specifically on it’s own (irrelevant of cadence).
Why stop ERG rides? I’m sure it will liven up the discussion, but ERG is all I do on the trainer.
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My thinking is when we ride outdoors there’s more variability due to the undulations of the road surface, uphills and downhills etc.
We get a more inconsistent pedalling experience including “micro-rests which means less stress on the knees.
Indoors on ERG mode we no longer get that experience and that’s why it feels harder because when a more intense segment turns on it’s basically “On”
and there is no pedalling variability…it’s harder, more intense and there are no “micro-rests” as we have outside.
- Very true in most cases.
Also true of ERG, but the same is true for Resistance & Standard modes (the only non-ERG modes TrainerRoad offers).
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RES & STD do have a different speed to resistance curve, but neither includes the variation that is present when riding outside. If a person holds a reasonably steady cadence, the power fluctuation that happens with all 3 of those modes is extremely similar. It can be seen in the power data of a workout and I have done just that in all 3 modes.
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The biggest difference that ERG offers is how it adds resistance to maintain a power target when a rider drops cadence. That is in contrast to RES & STD that drop power with a drop in cadence. This is the source of the common claim “that they are like outside”. It is true those more closely mimic the input to output change of cadence to power, but again they lack true variability.
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People often mistake ERG as some “perfect power” generator and it’s most certainly not that. No trainer responds fast enough to rider cadence variation to nullify power changes. Look at any power data chart from an ERG workout (specifically one without the horrible “ERG Mode Power Smoothing” that Wahoo defaults to) and you will see constant changes in power in tandem with slight cadence changes. Real power data shows ERG mode also includes subtle power changes.
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If a rider wants variability on par with outside, use of Simulation mode that is present in apps like Zwift, Rouvy, MyWhoosh and others is the direction to head.
For reference, here is a single 5-min segment from a steady state Endurance workout at low cadence in ERG:
Note the variation in power despite mostly steady cadence. This even includes a standing section around 30 seconds long right in the middle.
I did that partly to avoid overuse knee pain but I’m small light rider and Elite Suito trainer which saw me getting dragged into the ‘spiral of death’ too often and my stubbornness was creating extra strain. A lot of riders get on well with ERG though. Id have a look to see if there’s and underlying fit issue first, that’ll also stand you in good ground for pedalling outdoors.
Really great information…thanks for this.
Cheers
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Do you happen to have a video tutorial or something similar of said warmup. I’m very much willing to invest 10 mins before every ride but not sure what it would look like?
Ya…forgot about that “Spiral O Death” thing…it really does put a strain on the knees when you try to get it back up to speed.
Cheers
I do not, but he did tell me just last week that he was thinking of making one since this is such a common problem. I’ll get with him now and press him on it. lol