quick trainer/power question

frenchyge said:

Maybe it would make things more clear if you described what you did to *mitigate* the difference as opposed to "just keep riding and the problem goes away on it's own."

If the problem goes away on it's own, then the 'problem' is much like asking "I can't produce as much power in the aero position -- what gives?" Nothing really gives other than the fact that the rider is being forced to ride in a way that he's not comfortable with.

the problem is that races are conducted OUTSIDE (where inertial load is high) so addapting to riding inside with virutally no innertial load may be counter productive..

addapting to riding in an areo postition is productive because races are conducted in air if races were conducted in a vacuum addapting to riding in an areo postion would be useless...

one caveat... the pedalling style developed by pedaling efficiently without inertial load may or may not be a better pedalling style in general, that i don't know?

what did i change...

Step 1) opened the window for winter riding allowing me to get the room between 5-10C --> +10W-15W

Step 2) later, i went from using small 2.5" plastic rollers to using 4.5" heavier aluminum rollers --> an additional 5-10W

Step 3) this winter plan on purchasing an extra flywheel or two and i will tell you how that goes.. but as of now i am pretty close to what i can do outside and i can ride indoor or outdoors without any transition period

both of these changes allowed my number to go up. the change in rollers getting them within a few percent of my outdoor numbers and both changes allowed me to stay on the bike inside longer without the degree of concentration and addaptation as before, as well being able to use my outdoor numbers any time i got on the rollers, not having to judge level of addapation vs fitness vs. whatever.. being able to use your outside numbers inside is a huge deal in being able to know where you are in terms of your fitness, fatigue etc when you ride inside

RapDaddyo said:

You can make your argument as forcefully as you want, put words in bold, whatever you want to do is fine with me. But, what if what is going on with WW is that he is experiencing a completely normal period of adaptation to riding his trainer. You would have him believe that he needs a new trainer or some "technique" to solve a problem that you haven't determined he has. Why not prescribe some medication while you're at it for some virus that he may not have as well?

what you don't seem to understanding is that it's the transition that's the problem.. it's not just that your numbers aren't the same.. it's that they are not the same if go directly from road to inside... not the fact that you can train for a month and get your numbers up... why do i have to adapt... i'm letting the op know that no adaption is necessary... there is no need for any transition at all, that is my point.. not only that your addaption is to conditions that doesn't exist in the sport of cycling (which is conducted primarily outside and outside or indoor on a track with more inertial loading than you can buy a flywheel to simulate) unless your are a professional trainer/rollers rider

doctorSpoc said:

what you don't seem to understanding is that it's the transition that's the problem.. it's not just that your numbers aren't the same.. it's that they are not the same if go directly from road to inside... not the fact that you can train for a month and get your numbers up... why do i have to adapt... i'm letting the op know that no adaption is necessary... there is no need for any transition at all, that is my point.. not only that your addaption is to conditions that doesn't exist in the sport of cycling (which is conducted primarily outside and outside or indoor on a track with more inertial loading than you can buy a flywheel to simulate) unless your are a professional trainer/rollers rider

Maybe the published research just hasn't caught up with this phenomenon yet cyclingforums.comshowpost.phpOpen ↗.

RapDaddyo said:

Maybe the published research just hasn't caught up with this phenomenon yet cyclingforums.comshowpost.phpOpen ↗.

obviously...

i have not seen any research that addresses this issue directly.. even the papers Dr. Coggan provide me with don't address this issue directly and don't hold costant what needs to be held constant to test this phenomenon suitable.. so yes we i would agree with your statement "Maybe the published research just hasn't caught up with this phenomenon yet"..

there is not conclusive proof one way or the other, but Dr. Coggan agrees that inertial loading hypothesis makes sense...

dueling Dr. Coggan quotes..
http://www.cyclingforums.com/showpost.php?p=2885169&postcount=127

doctorSpoc said:

what you don't seem to understanding is that it's the transition that's the problem.. it's not just that your numbers aren't the same.. it's that they are not the same if go directly from road to inside... not the fact that you can train for a month and get your numbers up... why do i have to adapt... i'm letting the op know that no adaption is necessary... there is no need for any transition at all, that is my point.. not only that your addaption is to conditions that doesn't exist in the sport of cycling (which is conducted primarily outside and outside or indoor on a track with more inertial loading than you can buy a flywheel to simulate) unless your are a professional trainer/rollers rider

Actually, low inertial load conditions occur on the road during low-speed, high-resistance climbing, which tends to be a commonly trained-for condition. For me, the transition period is not a problem at all since once I go indoors I tend to stay indoors for a few months. Of course, people that switch back and forth with any regularity won't have any transition issues since they're staying adapted to both low and higher interial loading. Did you recently switch from exclusively outdoor to exclusively indoor riding, or have you been switching back and forth while trying out the open window and bigger rollers changes?

In any case, I have a Kinetic Road Machine trainer, have been riding outside since spring, ride in my unfinished basement where it's cooler than outside right now, and use a large box fan to generate airflow. In the next couple weeks I will be setting up the trainer and putting the training tire on my PT wheel, and I fully expect that again this year I'll experience the same thing that WW posted about. I also fully expect that within 2 weeks I'll be right back to full power again this year. If I experience anything different then I'll be sure to post it.

doctorSpoc said:

there is not conclusive proof one way or the other, but Dr. Coggan agrees that inertial loading hypothesis makes sense...

There's no question that riders respond poorly to the drastic change in inertial load caused by going from exclusively road to exclusively trainer riding. The question is whether it needs fixing, or whether one should just ride it out.

Hey guys, just for some clarification: I think I ride the trainer enough to be fairly adapted to it even this time of year (typically 1-2 rides per week, as recovery or race "opener" rides). My question was pretty much exclusively "do moderate temperatures with only a little airflow detract from power that much?" Obviously, riding the trainer in 50 degree temps is impossible right now, but won't be during the time of year i'll take trainer riding more seriously.

whoawhoa said:

Hey guys, just for some clarification: I think I ride the trainer enough to be fairly adapted to it even this time of year (typically 1-2 rides per week, as recovery or race "opener" rides). My question was pretty much exclusively "do moderate temperatures with only a little airflow detract from power that much?" Obviously, riding the trainer in 50 degree temps is impossible right now, but won't be during the time of year i'll take trainer riding more seriously.

Depends on what you meant by feeling 'trashed' after 10 minutes. If it's more of a generally tired, light-headed feeling, then I'd say overheating is a possible cause. If it was serious muscle fatigue and pain like I experienced, then I'd say no.

whoawhoa said:

Hey guys, just for some clarification: I think I ride the trainer enough to be fairly adapted to it even this time of year (typically 1-2 rides per week, as recovery or race "opener" rides). My question was pretty much exclusively "do moderate temperatures with only a little airflow detract from power that much?" Obviously, riding the trainer in 50 degree temps is impossible right now, but won't be during the time of year i'll take trainer riding more seriously.

Well I haven't seen any thread where people would complain suffering a significant power loss due to outdoor weather...

I ride outdoor at temperature between 60 and 100 I'd say. And I don't remember having quit the 1th of a 2x20 interval after only 8 minutes just like it happened to me the other day on the trainer. What I can confirm is that when the temperature goes over let's say 85, my HR during those threshold workouts is higher, but the perceived effort isn't significanlty higher (at least not enough to quit during the 1th interval).

I do blame the higher temperature indoor for adding some incomfort to the experience, which in turn adds to the loss of motivation to finish hard work.

SolarEnergy said:

Well I haven't seen any thread where people would complain suffering a significant power loss due to outdoor weather...

It's not the temperature per se, but rather the lack of airflow across the body to aid the evaporative cooling process that can produce overheating on the trainer even when riding in an air-conditioned gym or house. Sweat that pools and drips off the body is nearly worthless from a cooling perspective.

Personally, I think the effect on power production due to this is fairly minor, but some people may experience otherwise. 😉

frenchyge said:

If it's more of a generally tired, light-headed feeling, then I'd say overheating is a possible cause.

That would be the feeling. Some general weakness but certainly no bad muscular pain.

frenchyge said:

Actually, low inertial load conditions occur on the road during low-speed, high-resistance climbing, which tends to be a commonly trained-for condition.

this is a not a low inertial load condition... try holding your FTP power going downhill for 20mins, this should simulate what you experience inside.. probably going to need a 60 chainring but...

frenchyge said:

Did you recently switch from exclusively outdoor to exclusively indoor riding, or have you been switching back and forth while trying out the open window and bigger rollers changes?

~mid nov,dec - jan: transitional inside and outdoors don't really care that much about numbers because have clawed back my training anyway... end of season...

jan - march: indoors... start serious training... without inertial loading, have no idea where i am outdoors since my numbers don't translate directly.. with inertial loading know exactly where i am

march - april: transitional inside and outdoors... start serious training this is the worst period of time because i get addapted for outside very fast and lose inside addaption very fast so it makes it very hard to judge where i am in terms of fitness because numbers inside don't translate to outside etc so it's bascially like riding blind... a whole week can be outside followed by a whole week outdoors... with inertial loading there is again there are no issues

summer - almost exclusively outside except for bad weather days... without inertial loading these days are hard.. with inertial loading, even with the increased heat these days are ok...

but the point is mute because i don't have the problem any more because of my change in rollers.. any remaining small descrepancy will be taken care of by the addition of a flywheel this winter..

the arguement of why is interesting but not really essential... i know that if i increase inertial load i have no transition or it is is made very small... no issue... it really doesn't matter anymore why... it just works

frenchyge said:

There's no question that riders respond poorly to the drastic change in inertial load caused by going from exclusively road to exclusively trainer riding. The question is whether it needs fixing, or whether one should just ride it out.

yes the response is well observed, i was refering to the exact mechanism that causes this response...

what i think is important to understand though is that it is not in your head, there is a real physical/phyisological basis behind it and there is a solution if it bothers you... if it doesn't affect you or not so much that you don't mind the transition then there is nothing to fix... but if you are struggling or you are just not interested in addapting at all to a condition that you will not see outside... then there are ways to mitigate or illminate this problem.

doctorSpoc said:

this is a not a low inertial load condition... try holding your FTP power going downhill for 20mins, this should simulate what you experience inside.. probably going to need a 60 chainring but...

Climbing is high-resistance, low inertia because (obviously) the resistance to motion is very high, but the rider is typically in a very low gear which means the bike can be accelerated quickly. IOW, it's easy to accelerate the wheel, but it quickly rolls to a stop, just like the on a trainer.

Riding downhill is typically high inertia, but the reason some people have a hard time producing power downhill is because the resistance is so low. It's hard to accelerate the bike much and the spindown period is extremely long, just like a very large flywheel.

The inertial loading felt on the pedals is mostly a function of what gear the rider is in and the speed of the rear wheel. Solar's suggestion to ease the trainer resistance and ride a bigger gear helps allieviate the problem (ie, increase inertial loading) if one can still get sufficient resistance for their power needs. It might be a good idea to try for L2/L3 workouts.

frenchyge said:

Climbing is high-resistance, low inertia because (obviously) the resistance to motion is very high, but the rider is typically in a very low gear which means the bike can be accelerated quickly. IOW, it's easy to accelerate the wheel, but it quickly rolls to a stop, just like the on a trainer.

Riding downhill is typically high inertia, but the reason some people have a hard time producing power downhill is because the resistance is so low. It's hard to accelerate the bike much and the spindown period is extremely long, just like a very large flywheel.

The inertial loading felt on the pedals is mostly a function of what gear the rider is in and the speed of the rear wheel. Solar's suggestion to ease the trainer resistance and ride a bigger gear helps allieviate the problem (ie, increase inertial loading) if one can still get sufficient resistance for their power needs. It might be a good idea to try for L2/L3 workouts.

what???

i think you are a little confused.. outside inertia is mostly related to the weight of bike and rider since inside we can't really translate the bike and rider we simulate this by rotating things.. flywheels, rollers, wheels etc... outside the inertia associated with accelerating the wheels is puny compared with accelerating you and your bike.. but going up and downhill, i think you may have forgotton about this thing we call gravity...

the force of gravity... is accelerating all of us towards the center of the earth at 9.8m/s^2 at sea level... the ground exerts a force on your feet to counter act this. if it were not for the ground we would all be in free fall until we reached our terminal velocity ~200km/hr (force of gravity = drag)...

on a bike, if it were not for you pedaling and exerting a opposing force even to stay in the same spot much less to move up the hill you would roll down the hill ... you would accelerate down the hill 'til the force of gravity (related to your mass and dependant on the property of space call inertia) equaled by the drag associated with the rider + friction etc... but mostly drag... lets see.. a mass being acted on by a force and accelerating.. what does it take to counter act this?

going down hill the gravitational force is working in the direction of motion so you cannot be acting against this... sure the wheels on your bike are spining fast but the inertia associate with your wheels compared to you and your bike and drag is so small that they can be ignored.. you will accelerate 'til your drag equals the gravitational force and what you're pedalling is opposing is really just drag.. and this is just like inside.. very little inertial loading (wheels and things that rotate) and the opposing force is related to velocity... just like inside.. in one case it's drag.. and.. well if you use a fluid or wind trainer then inside it's drag too or it could be friction depending on your trainer or a little of both likely

i don't know about anyone else but i actually find it hard to accelerate going uphill. you find it easy to accelerate going uphill?? boy i don't want to climb with you... and i find it easy to accelerate going downhill...

what you've said just doesn't mesh with reality... it's easy to generate torque and power uphill because of lots of inertial loading not lack there of and downhill the opposite is true... i thought that was pretty obvious.

doctorSpoc said:

i don't know about anyone else but i actually find it hard to accelerate going uphill. you find it easy to accelerate going uphill?? boy i don't want to climb with you... and i find it easy to accelerate going downhill...

On an upgrade, the incremental application of power results in almost a 1:1 increase in bike speed (depends on the grade obviously), whereas the incremental application of power on a downgrade results in minimal increase in bike speed. For example, take a 5% upgrade vs. a 5% downgrade and a cyclist riding at 250W (rider + bike weigh 85kg). If the cyclist increases power by 10% (to 275W), he increases his speed by 8.35% on the upgrade and by only 1.17% on the downgrade. I realize that is speed and not acceleration, but acceleration is going to be proportional to change in speed. This is precisely why variable power pacing strategies are optimal for variable grade TT courses and why one always wants to increase power on the upgrades and decrease power on the downgrades.

doctorSpoc said:

i don't know about anyone else but i actually find it hard to accelerate going uphill. you find it easy to accelerate going uphill?? boy i don't want to climb with you... and i find it easy to accelerate going downhill...

Slow down a second and think about what I said. Going uphill in a small gear one can litterally feel the surge of the bike with *each downstroke*. Then the bike nearly rolls to a stop (if the hill is steep enough) as you're trying to get on top of the next downstroke. That's a quick acceleration on each downstroke and a quick deceleration through the dead spot (ie, very low inertial loading).

Then think about whether it feels the same going downhill. It's not a question of how easy it is (from an exertion standpoint), but rather how quickly or slowly it happens.

doctorSpoc said:

what you've said just doesn't mesh with reality... it's easy to generate torque and power uphill because of lots of inertial loading not lack there of and downhill the opposite is true... i thought that was pretty obvious.

It's not obvious, and in fact, many people have a difficult time seeing a second derivative function (like acceleration) in a physical sense. A decent background in physics or dynamics helps.

Is it deja vu, or have we argued about this before? I think it was with respect to mass/acceleration and resistance/velocity last time. The ability to generate torque is not caused by high inertia, but rather by high resistance. Try pedalling with the brakes on and see if your torque doesn't go up. Now figure out how you've managed to increase your mass simply by grabbing the brakes, and if you can do that then we can argue some more about inertial loading.

RapDaddyo said:

On an upgrade, the incremental application of power results in almost a 1:1 increase in bike speed (depends on the grade obviously), whereas the incremental application of power on a downgrade results in minimal increase in bike speed. For example, take a 5% upgrade vs. a 5% downgrade and a cyclist riding at 250W (rider + bike weigh 85kg). If the cyclist increases power by 10% (to 275W), he increases his speed by 8.35% on the upgrade and by only 1.17% on the downgrade. I realize that is speed and not acceleration, but acceleration is going to be proportional to change in speed. This is precisely why variable power pacing strategies are optimal for variable grade TT courses and why one always wants to increase power on the upgrades and decrease power on the downgrades.

and this is just what you'd expect given that the force of drag varies with the square of velocity.. but the force of gravity is constant and only dependant on your weight not your velocity.

when you are going uphill you are going slow so drag is very small so what you are really fighting is the constant linear force of gravity (you are also in the more linear part of the curve for drag to so even an increase in velocity will result in a some what proportional increase in drag.. it will be greater but not as proportionally bigger as at when going downhill at higher velocities)

i can excelerate from 20 to 80km in about a second going down a good hill (try that going uphill)... it's when i get past the terminal velocity for me on the grade is when the pain would start... because force of drag varies with the square of velocity and going downhill, velocity is much higher than going uphill and an increase in velocity results in much larger proportional increase in force of drag and the faster you go the greater the porportional increase.. (2-->4, 4-->16, 16-->256 etc.) this is the portion of the curve off to the right where force of drag would tends to the sky.

so yes, you would likely be much better off (have a higher ave veloclity in relation to to ave W for the whole ride) making a harder effort (more watts) against a constant linear force than one that increases as the square of velocity... as you say "the incremental application of power on a downgrade results in minimal increase in bike speed" [edit - and it's even worse than that after each incremental increase the next incremental increase has even less effect on speed, and the next less and the next less etc.] but this has nothing to do with weight or inertia and has everything to do with aerodynamics..

doctorSpoc said:

i have found as someone who has a problem with this transition, that if i add the element of inertial load (using a trainer with a heavy flywheel, using a big gear and less resistance etc) as well, your transition will be much easier and painless and you can bring all the numbers you have established outside, inside..

I've had the same experience as you (and most of us) - it feels tougher to generate the same power on the trainer as outdoors. I haven't tried a big flywheel, but I have tried my new CycleOps Fluid2 trainer that I got a month ago.

The resitance in the Fluid2 increases exponentially as speed increase, and the load at high speeds/power really feel more like outdoors than my Tacx I-magic. I have a much easier time to produce high power on the Fluid2 compared to my Tacx.

On my Tacx I also have a problem while standing, because it feels like there's not enough resitance to support my body weight on the downstroke, so I have to move some weight to my arms to support my body weight. On the Fluid2 it feels like there's more resistance so the acceleration of the pedal during my downstroke is lower. This supports my body weight better so that I don't have to use my arms to support my body weight.

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