so, how much did power go up after making your left/right balance more even?

can you provide your MMP data before and after power balance correction

For instance, I can claim that by having my wife train more, hitting certain target CTL and certrain distributions of time in various power zones, that she raised her power at all durations beyond 5 seconds over the season. I can demonstrate that a couple ways:

pick a few key durations and plot the best power efforts each month:
https://docs.google.com/...nK6XCc8Ig/edit#gid=0

or check out the MMP at 4 different periods throughout the season:



methods like this give you a good objective look at what, if anything has improved when you try a new training technique

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

If you read my post again, I specifically mentioned that by evening out my balance, I was able cause less fatigue on my dominant leg. I do believe that my overall power has increased, by approximately 4 or 5 watts but it is hard to quantify as that improvement could easily be due to improved fitness. The main reason for working so diligently on this discrepancy was due to the constant fatiguing of my more dominant leg (right). I believe it has paid big dividends with my running.

my impression on this.

-what make you think having proper balance 50-50 is the fastest way to ride a bike?

-how did you mesure fatigue in your dominant leg and the improvement?


I personally think that if you are in the 45-55 range, your wasting your time ''working on balance''/ Better focus on simply getting fittter and this will make you a faster athlete. There is nothing that show that faster athlete have better power balance.... and like swimming, many of us have one arms that does a different catch...stronger pull etc. It s part of how the body is.

Until someone can show me data instead of feelings, i highly douth working on balance is worthy.

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Jonathan Caron / Professional Coach / ironman champions / age group world champions
Jonnyo Coaching
Instargram

Thats a good, 60 W increase in FTP?

How did you verify the accuracy of your left and right power values?

My personal experience is that the "non dominant" leg is more dominant, IE if you played soccer then your plant leg as opposed to the kick leg is usually higher.

I would say that it has value to the extent that you can specifically identify problems, apply an intervention and then see an out come.

For example an athlete who had surgery and was 80/20 over time they get back to within a "normal" range, this sort of validates recovery and PT.

Or perhaps within the context of a good fitter they could identify leg length issues etc, throw a shim in and maybe see an imediate response with total power and balance etc.

As others have said not sure how you would or could isolate for less than 3-5% that would be tricky over time as there are other factors (recovery, training effect, fit intervention etc)

Maurice

You're presuming your performance is limited by leg strength which for most people, riding anywhere close to FTP, would be incorrect.

Saying "nothing to lose" is not accurate. I would say that you could lose actually working on something that will make you faster (increase your power) in order to work on something that may not have any impact at all.

pretty much the consensus right now among people who use power re: right/left balance is: So what?

The most applicable uses of L/R power balance as in the rehab field where people have undergone traumatic events that have severely impacted one of your legs. IED'd, amputation, partial lose of function.

Right now the research on R/L in sports is almost non existence/slim and doesn't support worrying about it except in the situation(s) described above.

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Brian Stover USAT LII
Accelerate3 Coaching
Insta

You lost me when you referred to SRM as needing to take their system to the next level, but I'll bit anyhow. Few people are really balanced evenly, but the differences don't mean much. I use a CompuTrainer and I have a slight bias for more power in my right leg. There are other interesting things, such as having a higher spinscan score for my right leg at recovery/endurance pace but at threshold my spinscan numbers are higher all around and higher on the left.

What does it all mean? Good luck if you can make any sense of it. To date the only useful application of the data seems to be in physical therapy to monitor imbalance due to injury and to measure progress in recovery. Even then the goal isn't to get to 50/50, but rather to level off at a reasonably balanced state.

A few things to consider.

1. Some people have permanent problems from severe long past injuries which are proven to be still impacting on performance, and or their training, by the ability to measure left right power output.

2. The mere fact there is little or no scientific research into something does not mean there is no benefit to be gained by furthering understanding by doing your own research.

20 years ago there was little or no research into power output of cyclists. 30 years ago there was little or no research into training with heart rate. 100 years ago there was little research into antibiotics. 200 years ago there was little or no research into pain relief or anaesthetics. Doctors and scientists were operating and amputating using filthy knives and saws with patients tied and held down in agony, who later died from infection.

Progress is made by embracing the technology available, not by disparaging or ignoring improvements, advances or new information.

If you are interested in power output and performance you should look at all the information available. Power output (of both legs) not just one leg, the power out put of each leg, heart rate , blood lactate and anything you can measure.

Don't be a Luddite.

There's actually a fairly large literature on asymmetry in sports/human movement, including studies of cycling by trained cyclists.

Funny. I don't pay attention at all to three of those and only sometimes do I glance at the fourth.

I don't look at any of them on the road. Indoors I only look at two of them in real time, but I record all of them.

It would be interesting to model those data and compare them to these results:

https://www.facebook.com/...ts/845145485507751:0

Their comment is also ignorant of SRM having had a detailed torque analysis option available before most (if not all) other commercial power meter came onto the market.

It also misunderstands the not insignificant difference between such data recorded on each crank arm independently vs those measured via net torque data from both cranks (such as SRM, Computrainer), with the latter probably more likely to be less useful, although the jury is still out on that.

Cycling related examples dealing with asymmetry:

http://www.ncbi.nlm.nih.gov/pubmed/978506
http://www.ncbi.nlm.nih.gov/pubmed/979569
http://www.ncbi.nlm.nih.gov/pubmed/10460126
http://www.ncbi.nlm.nih.gov/pubmed/15375819
http://www.ncbi.nlm.nih.gov/pubmed/17369798
http://www.ncbi.nlm.nih.gov/pubmed/21055708
http://www.ncbi.nlm.nih.gov/pubmed/22428419
http://www.jsc-journal.com/...15&path%5B%5D=46
http://www.jsc-journal.com/...23&path%5B%5D=75
http://www.ncbi.nlm.nih.gov/pubmed/24509507

Just a thought.

If you do have an imbalance the leg which contributes the most power will be subjected to a greater training load than the less powerful leg.

This greater training load should cause the more powerful leg to get even more powerful and the imbalance become ever greater.

But this isn't the case. So what is going on here? Why isn't the increased training load of the dominant leg improving that leg more than the less powerful leg which is doing less training?

Both legs are doing the same time training, the same cadence, but the more powerful is doing a more intense session.

If you were to separate the TSS between the legs, the more powerful leg will be getting a consistently higher score so why doesn't it increase its sustainable power by more watts than the less powerful leg?

My own imbalance only exists at lower powers. At maximum 20 minute power I'm near enough 50/50. At lower powers the imbalance can be as much as 44/56. I very rarely train at maximum 20 minute power. So almost all my training is done with one leg generating more power than the other, yet the imbalance remains the same, any improvement is divided equally between the legs. I would expect the weaker or lazier leg to improve less than the leg which is doing most work in training.

How come my lazy leg which trains less intensely is able to handle 50% of the work at maximum performance when it does so much less training?


Might my lazy leg which generates less power at lower power outputs in fact be the more powerful leg because it can perform as well in a maximal effort despite doing less training? Might my unconscious brain be deliberately training one leg more than the other?

How are you measuring this imbalance? Many such measures are not what people think they are and can be misleading. It's easy for two devices to report the same rider at the same time as being left and right dominant respectively. How it's measured matters.

I'd suggest an answer is that the forces involved at threshold are still relatively low and the limiter as you approach threshold is aerobic metabolic, not force. Our force limits even for the weaker leg are still much higher than the force demand at threshold. IOW a weaker leg can still generate the force required at threshold provided it has the aerobic capacity.

When operating well under both force and aerobic limits, well I can imagine normal neuromuscular and biomechanical asymmetries are probably amplified, when it doesn't matter that much. It only takes +/- 3W to give 52/48 at 150W.

What are you thinking Jack? Threshold test prior measuring efficiency, HR, balance, and wattage...work on improving that balance and then repeat test and compare.

At 150 watts I'm getting 12 watts less on the right leg, yet at 240 watts or 300 watts I'm near enough 50/50 sometimes 49/51 or 51/49.

Those are the averages over 20 minutes. The balance seems to be all over the place at the time but the average is consistent day to day.

I get the same results on Vector and Wattbike. But I have not used Vectors for years, only Wattbike. I got similar results on Look Keo a few years ago too, but they were unreliable so I don't trust their numbers, they seemed to consistently underestimate power at low force high cadence.

I don't see any reason to try and correct this, I'm just intrigued by how one leg can perform as well as the other when it consistently does less training,,or rather the same training but at a lower wattage.

Ok, quite a lot of studies that prove that there is indeed a significant power balance issue for several test groups.

But is there a study that shows that "improving" (ie becoming closer to a 50/50 L/R power balance) your balance will improve your cycling? Either by resulting in a larger overall power output (without added overall fitness) or improvements in injury prevention?

And how would you improve your balance? Just by focussing on it while riding on the trainer or can one do specific exercises to accomplish this?

Just asking because I recently bought Vektors and noticed that when cycling at race intensity, I have a rather large balance diff (42/58 L/R) and am wondering if and what to do about it.

It is difficult to know exactly what needs to be corrected based on a simple balance number.

I've been playing with the new Pioneer system with true L/R balance which changed my perspective a bit on L/R readings...

The discrepancy could be caused by leg imbalances, hip issues, bike fit (note to this that a pro bike fit may not pick up), all which may affect where/when you apply the most torque/power during the pedal stroke...

As mentioned above, you may see that number vary based on cadence and various power outpus, or the fact you ran yesterday and you have a running imbalance which fatigues your leg for bike training...

I totally agree there are several variables that are influencing the power balance. Although it might be hard to find exactly what is causing it, there is a significant imbalance as all mentioned studies have proven.

I know a lot of professional cyclists suffer from hip injuries caused by one leg being "naturally" stronger than the other. As I myself had some hip issues this season, I wonder weither or not they might be caused by the imbalance in cycling and if I could do something about it then.

And of course, improved overal power and efficiency is always welcome.