Road bike vs. recumbent comparison

[bladderhead]

the legs are getting less oxygen

It was a rush of blood to the head that caused me to buy the bike.

 

[ed72]

Maybe you should test an upright at the 90 degree angle like a comfort bike and compare that to the 90 degree recumbent. I seem to make more power on an upright the lower my torso is while also giving more aero benefit. Maybe that's why the pros don't ride comfort bikes. We know why they don't ride bents.

Why?

 

[ed72]

It was a rush of blood to the head that caused me to buy the bike.

Funny, your SN suggested liquid rather than gas.

 

[Gary123]

Uh I think it's against the rules.

 

[Osiris]

Read what Balor wrote. Maybe replace the hypothetical lard with a huge inefficient shock absorber that sucks up power from each pedal stroke.

Balor and I have discussed his theory on another forum. I have no doubt that there is some power loss due to tissue hysteresis, but I think he's overestimating it's effect on a recumbent while underestimating it's effect on a road bike. My experience suggests that something else is happening. Having ridden with a power meter for many years, I've become pretty good at estimating my power output by the amount of pressure I'm putting on the pedals. I know exactly what 300 watts feels like on my recumbents, so it's curious that producing 300 watts on my road bike feels much easier. The pedal pressure is much less, and I'm constantly amazed when I look at my readings that I'm putting out that amount of power. Cadence clearly has something to do with it. I'm much more comfortable pedaling at a higher cadence on a road bike, and increasing cadence produces more power without having to push harder on the pedals. So that would explain at least to some degree why I'm able to generate more power on a road bike while the level of effort feels the same. But the difference in power production is so dramatic that I'm inclined to think there must be something more to it than just higher cadence.

And in case anyone is tempted to ask, yes, I have tried to increase my cadence on the recumbent to see if I get the same result. The answer unfortunately is no, because pedaling as fast on the recumbent as I do on the road bike tires me out much sooner. I just cannot comfortably maintain 95-100 rpm on my Cruzbike (or any of my bents) like I can on a road bike. And to anticipate another often asked question, yes I'm using exactly the same Garmin Vector 3 power meter on my road bike and recumbent, so these differences cannot be explained away as an inconsistency between two different power meters.

Another difference between an upright and a recumbent is the orientation of the lungs and the initial effect on the V/Q ratio when one takes up the recumbent position. In short, the legs are getting less oxygen, which also explains the often heard.....my HR is lower on a bent.

That may be the case over longer distances. My power tests are generally anaerobic sprints. It would be interesting to see whether my FTP on a road bike is the same as on my bents, but I've never done such a comparison.

 

[RojoRacing]

When you go back and look at my strava history for past rides it's impossible to tell whether the ride was do on the V20 or DF unless I tagged them as one or the other. The HR data and power data is the same for both bikes. The only way to tell them apart are the average speeds for certain flat segments are slightly faster on the V20 but even then it's close enough to cast doubt on if the ride was for sure on one or the other. Same thing is true for the data post zwift race, if you look at them all together you can't tell them apart by bike.

 

[ed72]

So, I went back and re-read all of your posts and to be honest, all the talk about FTP and how easy 25 mph is what got me misunderstanding that TT efforts and not sprints were your concern.

On your road bike 4 years ago, your FTP was 210 watts and Peak Power (PP)was 1300 watts....4 years ago. On the V20, your FTP is 280 and Peak Power is around 1100 watts. Has your training plan changed? You do realize PP and FTP are inversely related as pertains to training focus? I suspect if you focused your training on sprints on the road bike, you would get back all the way to where you were 4 years ago unless you are old like me. (and your FTP would also drop)

FWIW.....I did not lose any power lowering my seat to 18 degrees from 20.5 degrees, my cadence is higher by 10-12 on the M5 compared to my uprights, my PP is at least 400 watts lower, FTP is 55-60 watts lower, and 5 minute power is 70-80 watts lower. Cadence is higher by choice to minimize force to knees, it seems obvious peak forces would be higher on a bent at the same power and cadence compared to sitting on a saddle unconstrained on an upright. HR also lower. I am sure my anaerobic outputs would be much higher on the V20. All of those are huge improvements for me over the past year and 9,000 miles of mostly structured training. The performance benefit to a much lower CdA depends upon the course and this will vary from rider to rider and one's understanding of hilly. I recall reading a bent rider claiming the hills at Sebring are "brutal".....

 

[Osiris]

So, I went back and re-read all of your posts and to be honest, all the talk about FTP and how easy 25 mph is what got me misunderstanding that TT efforts and not sprints were your concern.

On your road bike 4 years ago, your FTP was 210 watts and Peak Power (PP)was 1300 watts....4 years ago. On the V20, your FTP is 280 and Peak Power is around 1100 watts. Has your training plan changed? You do realize PP and FTP are inversely related as pertains to training focus? I suspect if you focused your training on sprints on the road bike, you would get back all the way to where you were 4 years ago unless you are old like me. (and your FTP would also drop)

I actually have no training plan. My rides just consist of a number of sprints in the areas where it's safe. I'm sure that my performance would improve, perhaps dramatically, if I trained regularly, but I just have too many things on my plate for that. I'm also pretty old by the way (58 in October), so whatever potential I once had has pretty much evaporated. Now I just settle for the occasional KOM and impromptu races against young riders who think they can beat an old man riding some strange contraption.

FWIW.....I did not lose any power lowering my seat to 18 degrees from 20.5 degrees, my cadence is higher by 10-12 on the M5 compared to my uprights, my PP is at least 400 watts lower, FTP is 55-60 watts lower, and 5 minute power is 70-80 watts lower. Cadence is higher by choice to minimize force to knees, it seems obvious peak forces would be higher on a bent at the same power and cadence compared to sitting on a saddle unconstrained on an upright. HR also lower. I am sure my anaerobic outputs would be much higher on the V20. All of those are huge improvements for me over the past year and 9,000 miles of mostly structured training. The performance benefit to a much lower CdA depends upon the course and this will vary from rider to rider and one's understanding of hilly. I recall reading a bent rider claiming the hills at Sebring are "brutal".....

Fortunately there are no real "hills" in Florida. At least not what we Northerners think of as hills. If there were, I wouldn't even be riding a recumbent. The downhill speeds would be insanely dangerous, assuming I could climb those hills on a bent.

 

[ed72]

Now I just settle for the occasional KOM and impromptu races against young riders who think they can beat an old man riding some strange contraption.



Fortunately there are no real "hills" in Florida. At least not what we Northerners think of as hills. If there were, I wouldn't even be riding a recumbent. The downhill speeds would be insanely dangerous, assuming I could climb those hills on a bent.

I'll never get the KOM on my local 10 mile TT course, it is 17:30. It is used for State Championships. Of the three thousand plus Strava runs on it, I am about 50th with a 22:02. If I had your 280 watts, I would be under 20 minutes and top 5. I am hoping to get under 21 minutes.....20:59 would be fine and dandy but it will probably take until next Spring or Summer to get it under 21 minutes. My best DF time on the course is in the mid 23 range, so, a bent is definitely faster for me on that route. On rolling 2-3 mile segments, I can take the KoMs if I want, a recumbent has such an advantage. On 10-15% hills? I can only say I make it up.

I generally keep it under 40 mph down hills on a bent and under 5o on an upright. 60 year old bones don't heal all that well and I'm still mending up from rotator cuff surgery........I fell off the bent onto the bad shoulder 4 days after surgery and lay on the ground using words that I never knew existed.

 

[jond]

On the subject of effort and HR comparison between DF and Bent to which I see zero difference in my numbers I must also add temperature and time of day have grossly underestimated effects on HR. I've changed up my schedule for work and I'm riding strait out of bed at 5am these last two weeks. It's not cold out here in the morning, in fact it is still like 70-75 degs at 5am but I've been observing some HR value even more odd then normal. My HR actual vs perceived is about 25bmp off so it's like my cardio is still sleeping while I'm riding. A normal threshold effort of 170bpm is only netting me 145bpm then I have to dial it back so much sooner then normal. I'm holding 200 watts at like 120bpm which is pretty damn low for me because it would normally be at least 145. Even weirder is the day before on the weekend I'll start a ride at 7:30am and be holding 170 all day long and maxing out at over 180 so go figure. Just keep in mind how you HR can change day to day.

You just need your morning cuppa tea coffee and donut breakfast heartstarter lol

 

[paco1961]

Aside from all the FTPs and power meter stats the bottom line for me is that I’m significantly faster on the CB with the exception of 7-8%+ hills and starts from zero. Certainly that’s part aero but for me likely also that my quads have always been a strong point for me. Back in my weight training days most muscle groups were typically painfully average while quad output was top of the chart. Lastly, the more open body angle on the CB gives me much better lung function. On my DFs I rarely rode in the drops because I always felt that it seriously reduced lung capacity.

 

[Balor]

I find it very strange how you people tell how your quads are limiting factor on a bent, while it was ALWAYS the other way around for me!
My hamstrings hurt from overuse for YEARS on a bent, while quads felt largely underutilized, and I've grown rather large quads from a few years riding DFs - they never felt 'underutilized' there as compared to hamstrings! Glutes - maybe, but not definitely not quads.

I was riding a pretty upright MTB even on brevets, btw - back issues.

I agree that I might overemphasize 'tissue hysteresis' aspect as far as non-obese people are involved, but in my case pushing against the seat seems so hugely ineffective that only 'scraping pedalling' (that recruits hamstrings heavily) seems at least somewhat effective. Bridging is somewhat of an exception, but I cannot maintain it for long.
Once I broken off the bars from my DIY MBB and was afraid to pull on them as much, my power dropped and all my rides fell short of my PRs and it took new MBB with bars I'm not afraid of pulling as hard as I could to beat them! (It is likely a bit more aero though... I really need to invest into a power meter). It also features position that is more open than of vendetta (very low BB), and I do feel that quads are more utilized, but whether from position or bar-pulling - I'm not sure.

I also have a hormonal imbalance and my fat is evenly spread around my torso, not concentrated in "aero belly".
By the way, is it a coincidence that people claiming to have similar FTP and even sprint power on a bent are known to be excellent climbers and sport very low BMIs (Tim Turner, Jason)? I think not, to be frank.

I really wish that bents would be allowed into triathlons. This way (tri people are usually quite wealthy) they would get advanced lab time (muscle oxygenation and recruitment, mechanical efficiency, etc) they deserve and we'll quickly find out what EXACTLY is going on. Or, at least people doing the testing will find out. Whether they'll share the data is an other question...
We really need to sort out not just 'transmission losses' issues (Margo Ruga research suggest that they certainly are an issue with RWD bents, but not nearly enough to explain the power gap - at least so far as stiff stick bikes are concerned), but bracing issues as well.

Also, it is not the first time I've heard about how maintaining high cadence on a bent is much harder, but there I have not the slightest idea how to explain that...

 

[Osiris]

I find it very strange how you people tell how your quads are limiting factor on a bent, while it was ALWAYS the other way around for me!
My hamstrings hurt from overuse for YEARS on a bent, while quads felt largely underutilized, and I've grown rather large quads from a few years riding DFs - they never felt 'underutilized' there as compared to hamstrings! Glutes - maybe, but not definitely not quads.

In the science of kinesiology you will find frequent references to something called the "angle of insertion". What this refers to is the points at which the various muscles attach to the bones. Basically, the further away from the joint a muscle attaches to the bone, the better leverage it will have. Angle of insertion differs from person to person, which is the reason some techniques work better than others for strength athletes like Olympic weight lifters and power lifters. It may be the case that the muscle groups acting on the hip joint in your case have a different angle of insertion from that of most people, so that the muscles are stressed differently.

Also, it is not the first time I've heard about how maintaining high cadence on a bent is much harder, but there I have not the slightest idea how to explain that...

For the doubters out there, it's very easy to verify on a trainer: just set the resistance very low and see how fast you can turn the pedals on a recumbent compared to a DF. In my case, I can pedal up to about 150 rpm on a DF, but it's very difficult to even reach 130 rpm on a bent. This will also differ from person to person. Kent Polk, for example, can pedal up to 180 rpm on his bent, though I don't know how that would compare to his performance on a DF. The fastest I've ever seen anyone pedal was an Olympic sprint racer who was clocked at 300 rpm on a DF.

 

[Balor]

Maximal cadence is a function of fast twitch fibers, there is a strong genetic component involved, as well as cadence-specific drills and crank length, so yea, absolute numbers don't tell us much...

 

[ed72]

On a DF riding under 75% of FTP on long events, my cadence is 72 on the flats. This is the most energy efficient cadence for me at around 210-215 watts. Faster speeds would dictate higher cadence for me.

On a bent, 82-85 rpm puts less stress on my knees on similar percent of FTP efforts. It just seems to me that the braced back puts more force into the knees on a bent compared to an unconstrained seating position on an upright. However, at higher power I have found an even higher cadence is better on a bent compared to the upright. So, I TT at closer to 90-93 rpm on the bent vs 82-85 on an upright. I also switched from Rotor QXL rings to regular round Dura Ace rings on the bent, this could be a factor.

I have no idea what my max rpm is on either. Never tried it. Not sure why it even matters. I did check GoldenCheetah and my max on the bent has been 131 rpm. I do know that part of my imprvement on a bent was working on neuromuscular firing and working on recruitment patterns. They may be the same muscles but the coordination between the muscles are slightly different on an upright compared to a bent. next time I get on a trainer (probably in December), I'll check my max cadence. I am also a midsole rider, so, this might also make me an outlier

 

[Osiris]

On a DF riding under 75% of FTP on long events, my cadence is 72 on the flats. This is the most energy efficient cadence for me at around 210-215 watts. Faster speeds would dictate higher cadence for me.

Yep, right around 80 rpm feels best to me on a bent. On a DF it's around 95 rpm.

On a bent, 82-85 rpm puts less stress on my knees on similar percent of FTP efforts. It just seems to me that the braced back puts more force into the knees on a bent compared to an unconstrained seating position on an upright. However, at higher power I have found an even higher cadence is better on a bent compared to the upright. So, I TT at closer to 90-93 rpm on the bent vs 82-85 on an upright. I also switched from Rotor QXL rings to regular round Dura Ace rings on the bent, this could be a factor.

The more racers and coaches I talk to, the less attention I pay to FTP. One coach told me that it's a "worthless number" for anything other than 40K TT races, where you actually do go flat out for one hour. When it comes to crit races, he tells me that there are many people with very high FTP's, but who have never won a single race.

I have no idea what my max rpm is on either. Never tried it. Not sure why it even matters.

Lots of training programs involve high cadence drills. I know that Kent Polk regularly does "spinning sessions" on his M5, which are essentially high cadence drills. Kent is an incredibly strong sprinter, capable of generating enough force to wheelie his Bacchetta CA2.

 

[paco1961]

High cadence drills were my biggest source of knee injuries. But then again as a life long runner before my cycling days I’ve always been a bit of a pedal masher. 90 ave on DF and 80-85 on CB

 

[ed72]

The more racers and coaches I talk to, the less attention I pay to FTP. One coach told me that it's a "worthless number" for anything other than 40K TT races, where you actually do go flat out for one hour. When it comes to crit races, he tells me that there are many people with very high FTP's, but who have never won a single race.

This sounds like something an amusing fellow who used to post on another forum would say. Areolius or something. Always sayin odd stuff. Anyway. FTP matters.

There are three key factors determining performance on shorter events of say under 2 hours, assuming proper motivation (willingness to suffer) and decent form (rest). Peak power, W' or known as high intensity energy (KJ above CP), and FTP or its similar analogs like LTP, MLSS, and others that similarly estimate the maximum power that can be consistently delivered from about 40-70 minutes in duration. Beyond say 3 hours, performance gets more complicated.

VO2 max can be barely increased whereas the percentage of VO2 max that one can tolerate can be trained. Unless one is a sprinter, few coaches or one training program that does not focus on FTP as a means of establishing training zones. (Maffetone approach is one). There are a couple of old school coaches that use RPE but the state of art is real-time display of maximum power available at a given effort, right on your Garmin. The next step might be integration of Best Bike Splits into essentially a race plan based upon power customized to a specific race, this sort of exists but you lose your turn by turn navigation on the Garmin and as a stinking lousy Randonneur, myself getting lost after riding 24+ straight hours is not fun. Training focus on aerobic power or FTP will cost Peak Power and vice versa. The focus of one's training is what is critical. I found that 3-5 minute power intervals with short RI to be very important to handle the carnage in crits but this does not mean FTP isn't important. I got back into Crits a few years ago in 55+ with former Cat 1/2 and fellows that were at the international level and when they dialed it up, the ability to suffer was the factor. Looking at my PM registering 120% of FTP for a very long time indeed had zero value; however, my 6x5 intervals at 115% of FTP were what allowed me to hold their wheels. So, in a sense your buddy is correct, FTP doesn't matter in a race but it surely does during training.

In my opinion, bent legs represent three phenomenon. Going from an upright to a bent requires certain adaptations. I'm not there yet after a year an over 9,000 miles of structured training which reminds me, I have to out for my interval ride. My focus is performance on a 10 mi TT and nothing is better judge of improve fitness than performance but then again, I have 14% improvement in FTP since May 11 and my TT has come down 90 seconds to 22:03.

 

[Osiris]

Training focus on aerobic power or FTP will cost Peak Power and vice versa.

This is a very interesting point. I don't understand why improving your aerobic power will cause a drop in peak power, though. I would have thought the two were unrelated. But if it is true, then I need to stop aerobic training immediately.

 

[ed72]

This is a very interesting point. I don't understand why improving your aerobic power will cause a drop in peak power, though. I would have thought the two were unrelated. But if it is true, then I need to stop aerobic training immediately.

For one and a very easy one, aerobic training converts Type IIb fibers to IIa. Getting deeper into it, there are three energy pathways with their own separate enzymes to ultimately get you ATP. If most of your work is aerobic or lets say under FTP, the focus of your training is not on the PCr or glycolysis; rather it is on beta oxidation to a large extent. A true road racer has little chance in a sprint against a track racer (genetis of coruse but also training specificity of focus). I do not believe it is an either or situation and can be a challenge to tailor one's Power Duration Curve. But in principle, lots of sprinting work with less aerobic training puts the focus on anaerobic pathways whereas focus on SST for instance would tend to raise ones threshold closer to VO2 max, which is what most cyclists want. They want to cruise faster with less effort. Your endocrine system can only take so much stress and many of these hormones are catabolic, which also works against say a sprinter doing 200-250 miles per week aerobic training. Throw a career and family in there and focus of training makes even more sense. So, it is not that true sprinters like Kilo riders don't do aerobic work, it a matter of specificity or focus of training. None of this applies to untrained or recreational because the will see rapid improvement across the board