Why riding like the pros is likely to make us worse

phreak
phreak Posts: 2,953
edited September 2015 in Training, fitness and health
http://www.ox.ac.uk/news/2015-09-14-pedalling-tour-winner-losing-strategy-most-us
Pedalling like Chris Froome or Alberto Contador might seem appealing, but Oxford University researchers have found that for most of us it’s likely to reduce rather than improve our performance.

A team from Oxford’s Nuffield Department of Clinical Neurosciences looked at a common measure of aerobic fitness called VO2 max. While it can be measured accurately in a laboratory, it is often more practical to use techniques that estimate VO2 max for individuals by getting them to exercise to their maximal level. These include the ‘bleep test’ of shuttle runs used by police forces and the Royal Air Force among others, or tests using a cycle ergometer, also known as an ‘exercise bike’.

The current calculation for a cycle ergometer is based on body mass in kilograms and work rate in Watts, but the Oxford team wanted to see if including the rate of pedalling, called ‘cadence’, would give a more accurate result, not only for VO2 max but especially for people who, often for health reasons like heart failure, cannot exercise to their maximal level. For these people, measurements have to be based on exercise carried out below the maximum level, making their result more of an estimate. Ensuring that estimate is as accurate as possible can be vital in developing appropriate health and fitness programmes for them.


Dr Federico Formenti led the research. He explained: ‘We used ten healthy men aged between 19 and 48. We measured the participants’ energy consumption at different cadences and exercise intensities, and used video-based motion analysis to study the mechanical determinants of changes in the energy cost.’

Professional cyclists pedal at a very high cadence, often above 100 revolutions per minute, for improved efficiency, and they can sustain very high exercise intensity for a long period of time. But Dr Formenti and his colleagues found that this was less effective for recreational cyclists.

Dr Formenti said: ‘We used mathematical models to show the degree to which energy required to spin the legs increases with cadence. At a low exercise intensity of 50 Watts, a recreational cyclist trying to pedal like a professional at 110 revolutions per minute will use more than 60% of their power just to spin their legs. Only 40% is going into overcoming the cycling resistance. To translate that to cycling on the road – only 40% of the energy you burn would be going into moving the bike forward.

‘Recreational cyclists want to pedal efficiently, just like the professionals do, but achieving that means pedalling differently from the professionals. Pedalling faster might work for Tour de France winners but it probably won’t work for the rest of us. At low exercise intensity, increasing cadence mostly results in a less effective stroke, reducing efficiency.’

Using the results of this study and other published results, Dr Formenti and colleagues have proposed a new and more accurate equation for estimating energy consumption on stationary cycle ergometers, using cadence as well as weight and exercise power.

Comments

  • It's a pointless article though because even on an easy ride I would have thought that most if not all of us will be putting out 100 watts and over and without knowing the efficiency at that level (along with 150 watts and 200) it would not be possible to say that a low cadence is better.
  • phreak
    phreak Posts: 2,953
    It's a pointless article though because even on an easy ride I would have thought that most if not all of us will be putting out 100 watts and over and without knowing the efficiency at that level (along with 150 watts and 200) it would not be possible to say that a low cadence is better.

    I think they went up to 150 watts. The full paper is here

    http://www.researchgate.net/publication/281741132_Pedaling_rate_is_an_important_determinant_of_human_oxygen_uptake_during_exercise_on_the_cycle_ergometer
  • I notice that the study did look at higher wattages but without the ability to understand the science I don't know the outcome.
  • Tom Dean
    Tom Dean Posts: 1,723
    The study has absolutely nothing to do with performance!
  • AK_jnr
    AK_jnr Posts: 717
    All I know is from getting used to my body I cannot ride at a low cadence, mine is naturally high and I'm sure it works for me.
  • sungod
    sungod Posts: 17,445
    higher cadence burns more energy, duh, their research is simply telling us what any experienced cyclist knows, but if it enables you to sustain higher power output, that's a good thing even if efficiency is lower

    presumably has some use for better estimating physiological parameters for the general population when undergoing health checks, but it's of little relevance to cycling as a sport
    my bike - faster than god's and twice as shiny
  • sungod
    sungod Posts: 17,445
    Yep, and burning more energy ultimately leads to less power, duh :wink:

    only if you run out of energy, which you won't do if you keep fueling, duh
    my bike - faster than god's and twice as shiny
  • Energy burned != sustainable power output.

    Does the report take into account adaptation? e.g. If you're a grinder and then you start spinning of course you're going to be less efficient and using more energy, you need time to adapt
  • phreak
    phreak Posts: 2,953
    Energy burned != sustainable power output.

    Does the report take into account adaptation? e.g. If you're a grinder and then you start spinning of course you're going to be less efficient and using more energy, you need time to adapt

    http://www.researchgate.net/publication/281741132_Pedaling_rate_is_an_important_determinant_of_human_oxygen_uptake_during_exercise_on_the_cycle_ergometer is the full paper, and you can also message the author from the same link.
  • As a research scientist, I love it when the mainstream media and general public try to interpret scientific research papers. Very recently, one of our papers got a lot of coverage in the press and in most of the new reports I wouldn't get past the 5th sentence before they had made a glaring error that totally misrepresented our paper and the conclusions that could be drawn from it. In some cases (*ahem* Daily Mail and Express) pretty much all of the editorialising was incorrect, unsubstantiated and/or misleading; the only accurate parts were the direct quotes and even then they were sometimes presented out of context or in a manner designed to misrepresent. The only mainstream outlet that did a decent job of covering our paper as it was written were The Guardian.

    My advice for anyone who is ACTUALLY interested in this is to read the original paper. The science is not that complicated, anyone with even a basic knowledge of science and exercise physiology should understand the basic concept that they were trying to convey.
  • So, spinning is up to 10 times harder work for the same wattage, hmmm, think I'll stick with a large chainring and a low cadence.

    This is precisely the kind of inappropriate reporting and extrapolation of conclusions that I'm talking about! Your direct quote of the authors is correct, but your summary is NOT accurate and your conclusions are NOT based on their evidence.

    Let me break it down for you:

    Firstly, the passage you quote is better summarised in the Discussion section is as follows:
    For any mechanical external work rate level considered in this study, mechanical internal work rate showed a 10-fold increase between pedaling rates of 50 and 110 revolutions per minute...

    This does NOT mean that "spinning is up to 10 times harder work for the same wattage", it means that the "mechanical internal work" component of the "total work" (effectively expressed as VO2 in this instance) increases 10-fold. You might regard this as pedantry, but this is a very important distinction. You're implying that holding a given wattage at a low cadence is 10-fold more more metabolically efficient than at a high cadence, that is not based on the facts presented in this study in the slightest.

    Secondly, and most importantly, you cannot extrapolate the data in this paper to infer that a low cadence leads to better performance in any metric (speed, power output etc etc) apart from metabolic efficiency unless you are certain that metabolic efficiency is a limiting factor. This is where the subject ties into a whole other myriad of factors that may affect your performance on race day, for example lactate accumulation (quite closely linked to metabolic activity) or muscle fatigue (not so closely linked to metabolic activity). To shortcut all of those considerations that and just say that "low cadence = metabolic efficiency = good performance" is not at all backed up by the facts presented in this study.

    To summarise in plain English for you:

    In science, words actually means things. You cannot go paraphrasing or extrapolating what the authors have said and expect it to mean the same thing. Often it doesn't mean the same thing at all and your essentially writing your own scientific paper, except you don't have any data to support what you're saying. If the authors had meant to say "using a low cadence will make you faster" they would have said exactly that. Their data did not support this conclusion, which is why they didn't say it. I hope that's clear.
  • No reporting, it wasn't a summary, it is just what I took away from it.

    Let me summarise what I said in plain English for you:

    They say 'spinning is up to 10 times harder work', I said 'I'll stick with a large chainring and a low cadence'.

    Yes, but my point is that they didn't say "spinning is up to 10 times harder work". You wrote that and it is not correct. Despite you saying it's not a summary, it clearly is. It is an incorrect statement and it has resulted in you misrepresenting the conclusions in their paper. :roll:

    I don't want to come across as a pedant, but as I said in a previous post, having had my work misrepresented by the general public and mainstream media, its immensely frustrating to see people wilfully disregard the key points of your research to blindly support their own agenda.

    With regard to technique, you can stick to whatever cadence you like, all I'm saying is that the only thing that this paper says that sticking with a low cadence will achieve will be to burn the fewest number of calories for a given power output. If that's what you want to achieve on a ride or a given portion of a ride then great, go for it but you cannot extrapolate that to anything else (e.g. performance) based on the data presented in their paper.
  • phreak
    phreak Posts: 2,953
    "Pedalling like Chris Froome or Alberto Contador might seem appealing, but Oxford University researchers have found that for most of us it’s likely to reduce rather than improve our performance."

    To be fair, that is from the Oxford website, so are you saying that their own comms team have misrepresented their findings?
  • "Pedalling like Chris Froome or Alberto Contador might seem appealing, but Oxford University researchers have found that for most of us it’s likely to reduce rather than improve our performance."

    To be fair, that is from the Oxford website, so are you saying that their own comms team have misrepresented their findings?
    University marketing departments are notorious for misrepresenting the science emanating from their own institutions and indeed are often responsible for the crummy misrepresentations made by the less science literate mass media that reports on it. Marketing depts and the media want eye catching headlines, click bait and "stories".
  • Without even reading the paper, what I take from it is a means to help improve the calorie estimations made by indoor training / spin bikes used by general public typically riding at modest power outputs.

    But it's likely to simply replace one generalised population based formula with another.

    People that pedal at lower power levels already naturally pedal at lower rates typically (recreational riders, those using bike for trip to the shops etc). As riders become fitter and race, pedalling rates naturally increase. Those in indoor trainer gyms are just hoping to burn a few calories in a vain hope of reducing the impact of the cake they have afterwards :)
  • University marketing departments are notorious for misrepresenting the science emanating from their own institutions and indeed are often responsible for the crummy misrepresentations made by the less science literate mass media that reports on it. Marketing depts and the media want eye catching headlines, click bait and "stories".

    Sadly you are correct. Wish they wouldn't do it, gives science a bad name.
  • If they are measuring oxygen consumption, i am not sure they are measuring the right thing. They should be measuring lactate concentration within the muscle/perceived discomfort which for most of us is the limiting factor on our threshold power output, and glycogen consumption/muscle fatigue, which limits the duration of our rides.

    Also testing 50-150watts is a joke, I'm overweight, middle aged, useless and have only been riding since feb, but i can do 200w sustained, most guys on this board are cranking out far in excess of this.

    I don't yet have power meter but the static bike at the gym seems to indicate 100 rpm @ 200w is my best sustainable effort.
  • But surely they are saying that it is harder work, if you're burning more calories for a given power output you are working harder...no?

    "Harder work" yes, but you said "up to 10 times harder work", which implies "up to 10 times more total work" and that is not what the paper says. It says 10 times more "internal work", which is only a small component of "total work".

    I can't be bothered to carry on explaining it. If you're still confused by this, I would just say from now on take any scientific reporting in the mainstream media with a huge pinch of salt because the critical parts are often in the detail that is either overlooked in the reporting or not appreciated by the subjects.
  • "Pedalling like Chris Froome or Alberto Contador might seem appealing, but Oxford University researchers have found that for most of us it’s likely to reduce rather than improve our performance."

    To be fair, that is from the Oxford website, so are you saying that their own comms team have misrepresented their findings?

    Unfortunately Alex Simmons is correct. A scientist would never have written that sentence, not least because of the huge implications of the word "performance". See my post above regarding that issue.

    If you want to hear a brief, accessible summary of a paper, either read the abstract or look for direct quotes from the scientists that did it. The language that they use is very particular and will not embellish or extrapolate the conclusions. Don't get me wrong, scientists always want to apply their research to as broad a conclusion as they can get away with, but they will not say anything unsubstantiated. Basically, if they didn't state it explicitly, you can't say it.