Power difference - indoor Vs outdoor - Page 2

Are we talking AP or NP here? My best ever AP numbers generally are obtained while climbing, though in a rolling race I will see 20M NP numbers that exceed my best 20AP (best AP 20 = 308; best NP 20 = 320). Just curious whether you are comparing apples to apples.

By the same token, I'd agree that sustained climbing is just different from flatland riding. Could be that as a flatlander you don't really climb enough to have optimized your power output whilst doing it.

And don't get the impression I'm a great climber either... got dropped so hard at Mt. Hamilton race in San Jose last weekend that it wasn't even funny.

I'm comparing NP to NP. NP was ~3% higher than AP on this climb because of the grade changes (from steep to OMG-steep).

I'm not sure who you're agreeing with, because I'm saying the opposite. Maybe the people who can't generate as much power on the flats just don't ride flats enough to optimize their power. In any case, I don't think there's anything that indictates that people should be able to sustain* more power output while going uphill.

* - continuous efforts ~15min or longer, where standing and pulling with the arms no longer provides a benefit (since this is not typically done during flat efforts).

Interesting re Outdoor v. Indoor. I started with power-SRM- in January. Going outdoors in March I was immediately at least 20w higher on my 2x20's, and by April, nearly 30w higher. In May I was back inside a couple of days, and was back down about 20w. My outside 2x20's were on relatively flat courses, usually into the wind. I thoght something was wrong with my SRM, but apparantly many of you have had similar experiences.

I have no idea why the trainer seems so much harder to me than the road, but it does. The interesting thing to me is that even though I live in Southern California where weather is not an issue very often, every top notch TT racer I know has spent a significant time on a trainer at some point. I found one recently who said he never uses one, but when I probed a bit I found that he'd come from Colorado and had spent many years on a trainer (just not recently). Maybe there's a corolation between the mental anguish and constant effort that goes along with both trainers and TT's. Any thoughts?

Cuz you live where you dont have to use one 5 mos per year

So we have no real concensus - some achieve higher power indoors (Ric - why do you think this is ?) and most seem to produce lower power indoors.
I do not believe it is just the mental challenge as the variance is too great, but I do believe the variance gets smaller the more practiced you are on the trainer.

I would love to get to the bottom of this...

I still think this may be it. Could you have them wear a heart rate monitor during the effort, if you don't already?

This past winter I road the trainer a lot, which I also use to estimate power. I occasionally used an hrm as well. This spring, I haven't had to ride it as much. When I did, however, I noticed a major plateu in interval power, despite feeling amazing while riding outside. At this point I never used a hrm. One day, I checked my heart rate using the count to 15, multiply by 4 method. It was almost 20 beats lower than what I had been riding at! This despite me feeling like I was working hard! I began wearing the hrm again. I don't pick any specific heart rate number, just use it for motivation. Once I got back up to typical heart rates I noticed a huge-as in 30 watt-jump in FT. So, 40 watts for someone who hasn't ridden the trainer that much sounds very reasonable. Just my 2 cents.

I actually think there is a consensus. The guys who run lab tests have tons of experience with this issue. My understanding is that they observe no meaningful difference in the power one can generate for a given duration indoors after adequate adaptation. There is a post to this effect from Andy C. on one of the trainer-related threads within the last 12 months. I have no idea why those who don't generate comparable power don't, unless they have not ridden a trainer regularly in the weeks preceding the effort or ventilation is inadequate. Although I guess motivation is an issue for some, because it is boring (at least for me).

Hi Paul

I am afraid that this does not really cut it for me. As a trainer of clients who are experiencing this with variances of up to 40w, it is a bit of a cop out for me to lay it all on "practice more" - it really does push ones credibility to attribute a variance this large to "adaptation" when the basic motion is the same indoor and out. Motivation might account for 5-10w but not 40w.

If there is in fact an "adaptation" issue, then what I am after is an explanation as to why this is the case given the similarity of the indoor and outdoor modalities. Why do I need to practice riding indoors and why does it elicit a lower power for the same effort and HR ?

At least if I have this explanation to hand then I can address the issue with a client before he comes to me broken and demotivated after not even getting close to his outdoor power when on the trainer.

Maybe you can get Andy or some of the guys who have run lab tests to weigh in on the adaptation period and why it is required. But, I'm pretty sure their answer is that there is no fundamental reason one cannot generate the exact same power indoors as outdoors after adequate adaptation.

Very unsatisfactory.. there has to be a reason surely ?

A reason for the requirement of a period of adaptation to riding indoors on a trainer before one generates comparable power? I suppose there is, but I think you started off with the assumption that the average trained cyclist generates less power on a trainer. That, I think, is an incorrect assumption.

Are you guys sure there is no physiological difference between an extended effort climbing and an extended effort on the flats? It seems to me (and I know I've heard it elsewhere) that climbing allows for either better muscle recruitment and/or the inclusion or distrubition of muscles used. For example, it's very hard on the flats (for me) to be able to move fore and back on the saddle to bring in slightly different muscles without feeling really sloppy. I usually just get on the nose of the saddle and stick there for hard efforts on the flats. With climbing, it just seems instinctual/natural to adjust position. With the front wheel raised, it also seems like the deadspot in the pedal stroke is not quite as pronounced, as if it is easier to push over the top and pull through on the bottom.

I'm fairly certain that I've heard that for climbing 2x20's to add 5% or so to your flat FTP for reasons similar to above. Peter, you might want to try raising the front end of the trainer an appropriate amount to simulate climbing an 8% grade or so. If your clients can come closer to their outside 2x20 climbing power with the trainer front end elevated, this may be your answer?

Peter-do you have your clients use heart rate while riding indoors? I re-read the beggining of the thread, and saw that you do, but you didn't say if your clients did or not.

Peter , how bout looking at power profiles and riding styles. I tend to ride rolling terrain and charge hills, rest a bit and then push again. Would different capabilities lend more toward indoor vs outdoor?