Road bike vs. recumbent comparison

[LarryOz]

My 2 cents:
I concur that it just "seems" easier to make power on a DF.
I was also surprised at how easily 200-300 watts would show up on a DF - virtualy with almost no effort at all - and even 700-800 for sustained periods when charging up a steep hill , but the perceived effort on my Vendetta for the same power (yes, using same pedals) is much higher, and wimpy me can just barely hit 800-900 for just 1 second on my V20 - but I am older than Osiris, so I claim the "age" card also.!
From my observations, I think there is somewhat of a loss of power on a bent due to your legs being horizontal and having to pedal that way (gravity). I also think that is one reason it just "seems" easier to generate power on a DF than on a bent. The other I think has to do with the length of cranks that you would use on a DF. I use 140's on a Vendetta, and 165-170 does not feel "bad" to me on a DF. I think this is because of how the pelvis and hips can swing down and from side to side easier and allow a longer crank and it is also not as hard to point the top when pushing down as compared to pushing out on a bent. (longer crank length - same RPM = more power. Yes, also easier to spin faster on DF. I have hit 140 on my V20, and can ride 1+ hour at 105, but have gone over 200 on a DF before. There there is also the advantage you get to standing up and swinging you whole body back and forth. It has an amazing affect. It can be done on a Cruzbike to some extent, but due to the angles involved the advantage is not as great. Still a benefit over RWD bents however.

 

[jond]

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

Horses for courses and nags for the knackery fields.

Of course as we age (and most of us here are getting on ) we are less capable and able in terms of explosive neuromuscular sprint efforts.

Far better then to focus on raising your threshold closer to VO2 max and getting the most out of your aerobic engine.

You see it’s way way way too much fun riding a cruzbike to limit your time. Or style of riding for that matter.

Of course we all have different goals and responsibilities impacting what we wish to do.

But one thing for sure. We are all quicker safer and more comfortable on a cruzbike 99% of the time no matter your goal.

 

[Balor]

My 2 cents:
I concur that it just "seems" easier to make power on a DF.

From my observations, I think there is somewhat of a loss of power on a bent due to your legs being horizontal and having to pedal that way (gravity). I also think that is one reason it just "seems" easier to generate power on a DF than on a bent.

Marco Ruga currently investigating that aspect and I think with some success. I'm heavily affected by that that - in a bent with high BB, I'm hit with severe numb feet - which is, essentially, nerve damage to hypoxia!
By the way, about ed72's comment about knee loads. I'm not sure at all that this is the case.
Any change in pedalling angle require 'readaptation' of the knees, of course (and cadence drills, and cranks length, etc), but what is fundamentally different with bents is, again, orientation of legs against gravity, hence somewhat impared blood flow, that includes blood supply of muscles, nerves and JOINTS.
Investigations of recumbent cycling (unfortunately, non-competitive, stationary exercise-related) show that knee loads are different, but not higher on a bent. But 'maintenence' of joins might be impaired, hence longer adaptation and achy knees from loads that are NOT higher than on DF.

MBB format is unique in that aspect - you can have large wheels, relatively low seat AND low bb AND short wheelbase at the same time. That comes with a sacrifice at aerodynamics, but given how your soles of your feet are much less oriented straight against the wind (flat plate drag - worst possible) with low BB - it don't think sacrifice is THAT great.

I've seen one 'Zockra'-type with BB as low as on DF...

 

[ed72]

Balor, I am not sure how to measure peak forces at the knee when pedaling (outside of a lab), so, my comment is obviously subjective and admit probably wrong. It is just an observation. I used to ride 10-15,000 miles per year on an upright and "never" had knee pains and I was a masher. You know PBP, I only used the small ring twice. I got knee pain once on an upright, I put a Brooks saddle on my bike before a 400K and didn't consider that the seat to crank height would change but I figured it out at around 200K and lowered the saddle. Anyway. When I go up some short steep 12-16% grades on my bent, I have to push hard against my thorax and scapula. It feels to me that the peak forces on the knee are higher on the bent despite lower absolute power levels. I do periodically get knee pain on a bent, I can't explain. I might be wrong. I was planning on experimenting with "normal" cleat position shoes in the off season instead of midsole that I have used for about 4 years to eliminate hot foot. I am reclined but not quite supine as in the linked study, which shows higher peak torque and lower VO2 max when laid back. Maybe need to try a cruz instead of hamster bars now that PT has me able to hold arm out without too much pain.

I too get numb feet after a few hours. Maybe I am just getting old and fat. The studies don't look so great but that gives us room to debate. .

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3737808/

"Thus, when choosing a bicycle to use for recreational purposes, results suggested that the stationary bicycle is the optimal choice for minimizing load on the knee"

http://www.umich.edu/~mvs330/f96/bikers/main.html

 

[ed72]

Horses for courses and nags for the knackery fields.

Of course as we age (and most of us here are getting on ) we are less capable and able in terms of explosive neuromuscular sprint efforts.

Far better then to focus on raising your threshold closer to VO2 max and getting the most out of your aerobic engine.

You see it’s way way way too much fun riding a cruzbike to limit your time. Or style of riding for that matter.

Of course we all have different goals and responsibilities impacting what we wish to do.

But one thing for sure. We are all quicker safer and more comfortable on a cruzbike 99% of the time no matter your goal.

Why does Larry crash so often?

I crash often on my M5.

Honest question.

 

[LarryOz]

Why does Larry crash so often?
I crash often on my M5.
Honest question.

The reports of my "often-ness" of crashing are are probably wildly exaggerated! haha
But, I will have to say, that probably 1/2 of my "sliding/crashes" were due to front flats at high speeds probably in a slight turn and usually going all out or close to it.
April 2015: 1 week before Calvin's Challenge. Front flat on track at high speed - rode to the ground - lots of road rash
Sebring 2016: front flat while going over 25mph on a local track; front rim hit ground, strechted out left arm, causing left shoulder to dislocate

Others that I can think of that were the worst (and not due to flats) - possibly pilot error, but probably not avoidable either:
Sebring 2015: ran off racetrack after 23 hours of riding, wheel got caught in crack and I went down on my right shoulder
Local group ride 2016 : hit sand in a corner while traveling over 30mph - no chance to re-act - just rode the bike to the ground and lucky an on-coming car did not run me over
Sept 2017: High cross-winds knocked me over while doing 35+ on Charlotte motor speedway - was on my way to sub 50min- 40K that day - was not wearing gloves - which was a BAD idea.

Since I have been riding Tubeless (about past 2 years) I have had far less flats, and when I have, I have been able to stop the bike and not crash.
Worst was RAAM last year (2016) going downhill at 30+mph in the middle on the night on "debris laden" edge of a divided highway. Hit something "big and sharp". ProOne went flat almost instantly. It was tough, but I managed to muscle the bike to a stop without wrecking. It was close though and I was pretty scared while it was happening! I was a little more tentative after that at night.
To me, the nicest thing about the tubeless is that the tire stays on the rim almost like a tubular, which allows you to stop the bike safely in most cases.

Having said all this, and since this thread is about "Road bike vs. recumbent comparison" , I will have to say that most of my wrecks: whether they were due to front flats or road conditions were probably because I was riding close to maximal effort (i.e. racing or training at a high output; right on the edge = max speeds, etc). I probably would not have crashed (or slid) if I was just out enjoying the ride at 15mph or less. Sure there is some inherent sliding problems with the FWD-MBB platform when the front wheel goes flat fast or you encounter loose material under you tire, especially when you are laying back at 20 degrees. DF have a definite advantage there for recovery since the balance aspect is so different. The one big advantage of "crashing" on a recumbent is that it is more "sliding" than crashing. On a DF - you have a lot farther to fall, and it usually involves hitting your face, head, or shoulders from a higher distance.

 

[bladderhead]

I was talking to this bloke who was sure my bike was not safe. Eventually he told me his front teeth were false due to him going over the bars and eating some street furniture.

 

[jond]

Why does Larry crash so often?

I crash often on my M5.

Honest question.

Well he rides a lot and on the rivet.

And truth is he crashes no more or less than the next cyclist. He merely generously makes public his entire cycling experience.

Getting a flat at high speed is a lottery.

But if I’m to crash it’s the vendetta that offers the best way to do it.

If you think about it after every crash comes apprehension before you bomb the next downhill at 100 klm\hr.

We are nuts.

 

[jond]

I reckon if you can brace your back against a bent seat then your absolute neuromuscular power potential is made able so more power is possible on a bent not less dependent on seat back angle.

To the point where you can hurt yourself.

I reckon laying down my heart works less hard. As such I need to mind my numbers less I relax too much into free smart speed.

On a df 1200 audax my lower legs will swell a bit by last day. This does not happen on the vendetta. So easier better circulation more circulatory efficiency not less.

Heck doesn’t everyone do their best work laying down. Lol.

My knees are at eye level. I can get hot foot on a df as well as the v but a mid sole cleat solved that on the bent.

We are debating discussion really of very interesting but personal minor physiological differences at the neuromuscular effort across platforms .

I think this is an individual scenario related to individual physiology and not platform related comparing df to vendetta where framesets are both very stiff.

Rojo and myself note no differences in numbers across platforms so I reckon for me there is none. Unless we are talking speed safety or comfort of course.

What isn’t in question are those incredible basic gains that led us all to stay on bents.

It is really unfair to compare any df to a cruzbike as to me the cruzbike is scientifically the superior smarter safer faster comfortable machine in all scenarios except weight and climbing big big hills slowly.

Of course the smart vendetta has some disadvantages but they are few compared to the dumb stagnant boring df design we are presumably designated to be stuck with.

Opinion only . cruzbike nailed it with 20 degree recline on the vendetta in regards to aero/power generation in a stiff reactive whole allowing upper body input that is both fun and practical.

I would not want to be supine no matter.

 

[Balor]

When I go up some short steep 12-16% grades on my bent, I have to push hard against my thorax and scapula. It feels to me that the peak forces on the knee are higher on the bent despite lower absolute power levels.

You powers is less. Your cadence is higher. Is it even physically possible to have higher peak loads on joints that way?

In theory, if you a gym monster and used to squatting a few times your own weight, on a bent you should be able to output truly monstrous torques at low cadence.
But in practice, NOBODY does that, as it seems!

I'm also a masher on DF. I also, once my knees adapted, didn't have any problems despite never being a lightweight even at peak of my form.
Yes, my knees also hurt for a long time after switch to bents - but I blame 'reconditioning'.
After switching to a new position and shorter cranks my knees started complaining again, but after about 400 miles they seem to adapt again.
I suspect that knee adaptation is specific to loads encountered, not 'general'. Being a marathon runner does NOT guarantee that you will not get knee pains when cycling long distance, despite higher (in fact, impact) loads on knees.

Article about supine vs recumbent is interesting in explaining why not everyone can adapt and output high power in supine (very low recline) position.

As for that data:

http://www.umich.edu/~mvs330/f96/bikers/main.html
I have no idea how they arrived to this conclusion.

Admittedly, when pedalling STANDING, there is a very marked difference at loads on the knees - they are much less bent when delivering peak torques, in my pedalling style I nearly 'jump on top' the pedals (it also explains why my chains didn't live long before I switched to waxing, lol).
If you could not stand on pedals ever, would you also have problems with knees on DF?

 

[Balor]

On a df 1200 audax my lower legs will swell a bit by last day. This does not happen on the vendetta. So easier better circulation more circulatory efficiency not less.

Better venous RETURN blood flow on a bent with feet higher than heart is in the 'well, duh!' territory. Vice versa though...

P.S.
To force oxygenated blood into capillaries to deliver them to your tissues blood needs enough pressure.
Blood pressure drops when feet are elevated. Whether it affects you depends on how 'robust' your vascular system is, I suppose. In my case effects are pretty severe.

 

[ed72]

You powers is less. Your cadence is higher. Is it even physically possible to have higher peak loads on joints that way?

The forces to the pedals? Those should be equivalent or thereabouts. There could be some small variation compared to a DF.

I am talking about forces to the knee. I presume there is a fulcrum effect at the knee to some extent on a bent and for sure there are several roation points. Physical Therapists usually start knee treatments on uprights for a reason. I do not have much of a physiological reference to support my "theory" but please see the linked. There are about 8 degrees of freedom to describe the motion. Most models assume the knee to be a simple hinge in two dimensions but it isn't that simple. Pedaling efficiently is very complicated and takes years to perfect. You are a lot smarter than I. I spent many years becoming efficient on an upright. I am trying to develop my best pedaling on a bent but to be honest, there isn't much science out there on it but there is a lot of dogma. I do not have much information on the Kent Polk seat but to me it makes sense because it should allow better use of the psoas and hip flexors and extension muscles because the "butt" can move along. I can visual that this less constrained motion would also result in a move even torque delivery over the full pedal stroke with lower peak forces at the knee. The pelvis is not exactly stationary on an upright. As the foot comes over the top, you can see movement of the hip and especially the foot. This is to minimize sheer forces and of course, to get into the powerstroke sooner.

Why else would bent riders gravitate towards short cranks and higher cadence? To reduce knee pain by reducing peak forces on the knee (certainly sheer forces coming over the top)

I know that trying to push a big gear up a hill on a bent tends to cause some knee pain for me, thus, I changed my technique to higher overall cadence on the flats but much higher relatively when climbing and pain went away.

"These results indicated that the knee joint torque might be influenced by the small movements at the hip joint"

https://ojs.ub.uni-konstanz.de/cpa/article/download/4234/3930

"Joint reactions forces, particularly at the knee, were highly sensitive to changes in knee joint model kinematics, as high as 61% root mean squared difference, normalized by the corresponding peak force of the unaltered reference model. Muscle forces were also sensitive, as high as 30% root mean squared difference. Muscle excitations were less sensitive. The observed changes in muscle force and joint reaction forces were caused primarily by changes in the moment arms and musculotendon lengths of the quadriceps"

http://biomechanical.asmedigitalcollection.asme.org/article.aspx?articleid=1475826

"Verbal feedback from the subjects appear to support this curvilinear trend and perfonnance differences. In the 25° hip position the subjects indicated that Effect of Hip Position in Cycling 367 muscle fatigue was greatest in the quadriceps region, whereas it was greatest and localized in the gluteal area for the 100° hip position. However, in the 75° hip position the subjects reported muscular fatigue to be more generalized throughout the lower extremities. This would suggest that the 75° hip position and similar ones allow for a more equitable distribution of load over the various muscle groups involved"

https://digitalcommons.brockport.edu/cgi/viewcontent.cgi?article=1093&context=pes_facpub

Although the forces at the pedals are similar on a bent and upright, the concentration of forces and kinematics are certainly different. Again, why do bent riders gravitate towards shorter cranks and higher cadence?

 

[ed72]

And truth is he crashes no more or less than the next cyclist. He merely generously makes public his entire cycling experience.

Must be me. Crashes on an upright over 40 years were extraordinarily rare compared to a bent. There must be some physics involved. And a front flat never once took me down on upright but not so on a bent. First front tire flat on the bent....down. As I said, must be me. Over and out.

 

[Balor]

I am talking about forces to the knee. I presume there is a fulcrum effect at the knee to some extent on a bent and for sure there are several roation points. Physical Therapists usually start knee treatments on uprights for a reason. I do not have much of a physiological reference to support my "theory" but please see the linked. There are about 8 degrees of freedom to describe the motion. Most models assume the knee to be a simple hinge in two dimensions but it isn't that simple. Pedaling efficiently is very complicated and takes years to perfect. You are a lot smarter than I.

Coming from you, the latter sounds like an unsubtle mockery to me . I've just spend way too much time thinking about same questions, and I'm not quite sure my answers are correct, obviously.
I'm just making a 'common sense' guess, but nothing is simple about biomechanics and physiology...

Although the forces at the pedals are similar on a bent and upright, the concentration of forces and kinematics are certainly different. Again, why do bent riders gravitate towards shorter cranks and higher cadence?

Well, joints need blood supply just like any tissue, and on a bent your knees are actually your 'highest point', hence blood supply must be limited compared to 'normal operation', the higher BB is in relation to the seat, the greater the effect.
More than that, I suspect that such a position may also negatively impact lubrication by synovial fluid, but how can one test for that - I have no idea.
The research that I had in mind is this, but only abstract is available (same authors):

https://www.ncbi.nlm.nih.gov/pubmed/15133932
https://www.ncbi.nlm.nih.gov/pubmed/12085603

In particular:
Additionally, the amount of work done by knee flexion was significantly increased in the RCP while total work at the knee was not different.

That is what I mean by 'scraping pedalling' and I explain it as alternative to bracing against the seat. I use it a LOT, myself, and getting better and better at it. The process is very slow for some reason, however.
But without detailed information this is basically 'my word against yours'...

I'll get some hands on (anecdotal, of course) data after I'll install shoulder boosters on my MBB with very low BB and see whether I'll be able to tolerate higher loads compared to my previous bents with BB higher than the seat.
While I'm getting better at 'scraping pedalling' a ton of research you very well know indicates that 'push-push' style is more effective and I can attest to that when I swap to niner DF.

Anyway, I've never had 'true LWBs' like Tour Easy, but people unanimously claim such beast to be 'much faster than they should be'. There can be multiple reasons for that, but really low BB might well can play a role - both from bracing and blood supply theories.

 

[Balor]

There must be some physics involved. And a front flat never once took me down on upright but not so on a bent. First front tire flat on the bent....down.

Yea, very simple physics, actually. When you lie nearly flat, you cannot do 'body English balancing act' as compared to DF, hence you must do all the balancing by steering.
Flat front tire - no grip - no steering - down you go, as simple as that. On DF you can lean back and forth and even shift the bike under you. When you sit bolt upright, you balance in slippery conditions is massively improved - that's how I negotiate loose and slippery stuff myself, but even then it is only a fraction of freedom DF position gives you when you stand on pedals.

 

[ed72]

Balor.....I thought you misunderstood what I was saying. As an anecdote to the scraping idea, when lowering my seat from 20.5 degreees to 18, I expected lower power. I did not see that. On the contrary, my 5 minute power was up significantly but my FTP stayed the same. I noticed a somewhat more natural feeling at the hips meaning less constrained. Based upon that small revelation (to me), it dawned on me that Kent Polk was onto something WRT to seat design. I am going to mess around more with your pedal scraping......in the off season......with pedals mounted over the ball of the foot instead of mid-sole. I almost think ankling might be a bit of the secret sauce to your theory. I did try it midsole on the trainer, it is is hard to be sure but it seemed 10-15 watts additional appeared but I am not sure. I also have noted many times how a particularly successful female bent racer is really extended and it has perplexed me because there is no arguing with performance. One think is abundantly clear to my pedal stroke, sitting up on a steep hill gives me a large anaerobic boast in power......very noticeable. I am thinking a normal cleat position with more extension might allow better engagement of the glutes. I admit to poking around in the dark here.

 

[Balor]

I'm not sure that ankling helps a lot - I have cleat as low as possible... still not nearly as low as midfoot, though. In my case it helps greatly with severe varus and flat foot problems - otherwise my feet start hurting a great deal.

Btw, it is MUCH more noticeable on a bent than on DF... yet it is much more apparent with walking, I can barely walk for more than a hour without limping. Obviously, too much weight is to blame, too.
I suspect if you move from midfoot, you'll numb feet issue might get much worse.

 

[Balor]

One think is abundantly clear to my pedal stroke, sitting up on a steep hill gives me a large anaerobic boast in power......very noticeable. I am thinking a normal cleat position with more extension might allow better engagement of the glutes. I admit to poking around in the dark here.

I've tried that. Does not seem to work for me... of course it helps with the steering like I said, but my power drops. I blame 'tissue hysteresis' again - pulling the bars is much harder when they are in your chest, so I'm left with scraping and pushing with my, ahem, 'lower back'.

 

[ed72]

I'm not sure that ankling helps a lot - I have cleat as low as possible... still not nearly as low as midfoot, though. In my case it helps greatly with severe varus and flat foot problems - otherwise my feet start hurting a great deal.

FitWerks in Peabody Mass did a fitting for me a few years ago and put a varus wedge in the front of my right shoe. It helped me. They had asked towards the end of a TT fitting if I had any pains and I told him that I had a weird one on my foot that I attributed to a poorly healed broken ankle from a slap shot in hockey. I can't remember what the ache was in my foot and felt silly telling them it only happened over 100 miles and he goes, "you must be a randonneur" and it turns out he fit Melinda Lyon (le Premiere Feminine on PBP....oh wait, it is not a race) and he said he understood. Spent some extra time with me. Puts different wedges and hooks me up to a pedaling gizmo onto a big screen measuring pedal forces and a number indicating efficiency. Ache gone. It is almost that we need someone like that for recumbents. I'd like to get totally dialed in on a recumbent in the same way. I would love to get rid of the numb feet on a bent. Maybe I just need more time. The acid reflux took 9 months to disappear and the need to pee five times in the first hours is getting better.

 

[bladderhead]

I think there is something in all this talk about blood and feet being elevated. My power on a 'bent is limited by breathlessness. Actually I hardly ever sprint, because it always nearly kills me. There is a long hill near me, and I can only just reach the top, and my lungs are working to the max. I never go at maximum effort, because I know that if I do I will have to stop. The only way to get up that bastard is to go slowly on purpose. I never thought about this when I rode a DF. Maybe I need to wear some kind of vest that squeezes my body so the blood is pushed into my legs.

Here is another bit of anecdotal evidence for you: I am a mid-footer, and I turn my ankles and scrape, because it seems to give me a tiny bit more power for the same effort. I need every bit I can get.