Compu-Trainer Classes: Why train with power? & Pedal Efficiency!

Compu-Trainer Classes: Why train with power? & Pedal Efficiency!

By Rich Staley/on November 2, 2012/in Blog

There are many options out there, and the new thing is to train with Compu-Trainers.  They are stationary stands that you put your own bike into, and you ride in place.  The Compu-Trainers are the stands that you put your bike into.  However, the twist is that the Compu-Trainer units are all computer controlled.  Up to 8 people can ride at one time, and the computer will will keep track of each person, and will allow each rider to interact with other.  We pick a course that we have written that has climbs, descents, and flats.  Each rider rides the same course, and can draft other riders across the course.  The Compu-Trainer units will control the drag factor on your rear wheel by increasing or decreasing the drag dependent on how much you weigh, and what percent grade you are going up or down.  Then the computer will cut the resistance to your unit by about 30% if you are drafting another rider.  This allows riders to work together to get across the course.  Not for the nitty gritty.

The nice thing about Compu-Trianers is that they track power.  So, we can see what power you are putting out, and for how long.  This is only important to you and only you.  There are three things to look at that many others miss:

First:  Power.  How many watts do you put out.  Another way to look at this number is by looking at how many calories you burn.  But here is a problem.  Lets say that you weigh 155 lbs, and  can put out 250 watts for one hour, but the guy next to you weighs 195 lbs  can put out 300 watts.  From initial outlook, it would appear that the 300 watt rider (or the rider that burns more calories for the hour) is the stronger rider.  Heck, he or she is putting out 50 more watts, so they must be stronger, right?  The thing that many people miss is taking rider weight into consideration.  Lets say that you weigh 155 lbs (70.3 kg), and the other rider weighs 195lbs (88.45 kg).  Then if you take the total watts and divide by the riders weight in kg’s then you quickly realize that the 155 lb rider puts out 3.56 watts per kg of weight, and the 195 lb rider puts out 3.39 watts per kg of weight.  So, in this example, the 155 lb rider is working harder, and going faster.  Sorry to put this all in metric, but that is how all the systems work.  This is the first problem with power.  You always have to take the riders weight into consideration when comparing your watts to another riders wattage output.  An easier way to put this is to take a Corvette engine and put it in a go cart.  Then take the same engine and put it in a PeterBuilt truck.  Both engines put out the same amount of power or wattage, but the go cart will go much faster because it weighs less.  Same thing between the two riders.  The lighter rider does not have to put out as much power to keep up with the heavier rider.  So, don’t get caught comparing power output (watts), compare with power to weight ratio, or watts per Kg.

Second: Efficiency.  Lets take our same two riders, but this time weight is not  an issue.  Lets say that both rider weight the same.  Lets also say that one rider can sprint at 1000 watts, and the other rider can sprint at 1400 watts.  The question is who is going to win in the sprint.  Initially it looks as if the 1400 watt rider is going to win the sprint.  But this may not be true.  This is where efficiency comes into play.  Efficiency in cycling is defined by how much you push compared to how much you pull with the opposing leg.  When one leg is pushing down, the other should be sweeping back and pulling up.  Here is the fun fact.  ALL OF YOUR FORWARD MOMENTUM OR SPEED COMES FROM YOUR QUADS!  So, this brings us back to efficiency.  Your quads give you a potential for a given speed.  If you don’t have an efficient pedal stroke, than much of the energy from your quads ends being used up to lift your opposing leg.  So, by not being efficient, and not sweeping and lifting the opposing leg, you are cutting into your potential speed.  But you are not cutting into your wattage or power output.  You are just limiting how many of those watts go to forward momentum, and how many of those watts lift the opposing leg.  Legs go back to our example.  With the same weight riders, if the first rider can sprint at 1000 watts, and is running an 80% efficient pedal stroke, then 20% of his watts are being lost to lifting the opposing leg.  So, this first rider ends up sprinting at 80% of 1000 watts, or has an 800 watt forward momentum sprint.  Now lets say that the 1400 watt sprinter has a 50% efficient pedal stroke.  This would mean that this rider has 50% of his wattage going into the sprint, and the remainder 50% of his watts lifting his opposing leg.  That puts this sprinter at a 700 watt sprint.  So this puts the 1000 watt sprinter at 80% efficiency ahead of the 1400 watt sprinter at 50% efficiency  by 100 watts.

So, what the heck does all of this mean?  Simply put, “If you build it, they will come!”  If you work on your pedal stroke, and become more efficient, then you end up having more muscle groups helping propel you along.  So, you have more engines driving the train.  The coolest thing here is that once you realize how to pedal efficiently, you end up producing more power (watts), end up going faster, and your heart rate and breathing rate end up dropping.  It is such an amazing thing to realize, especially when you are climbing.  You will climb faster, with less perceived effort, it will make your century rides more enjoyable, and your cycling experience more enjoyable.  When you get that efficiency above 75% you end up bouncing less on the saddle, which is a good thing for obvious reasons, your feet don’t go asleep any more, you don’t get chafing from the saddle, and it is just amazing how many things fix themselves just by pedaling efficiently.

Third: Cadence.  I constantly hear trainers telling people to pedal with heel down, and with a high cadence.  They claim that a high cadence forces efficiency, and that pedaling with your heel down gives you more power.  I mostly agree with this…..  MOSTLY!  Here is the hitch.  I challenge everyone to go to YouTube, and type in “Tour De France Time Trial” and watch every pro cyclists feet.  You will quickly realize that every cyclist pedals heel down to about the bottom 1/3 rd of the pedal stroke, then their toes drop and they pedal through the rest of the pedal stroke with their heel up.  Then at the top of the pedal stroke they drop their heel back down again.  The human body is strongest pushing with their heel down, but we humans have muscle structures that pull up best with our heels up.  Try it.  Put a box of rocks in front of you, sit down and push the box with your toes (heels up), then push it with your heels (heels down).  Much easier to push with your heels than with your toes.   Then repeat by tying a bag of rocks to your foot.  Then lift with your toes lifted up, then again with your toes down (heels up).  You will again quickly realize that you can lift the bag of rocks up easiest when your toes are down and heels are up.  Our hamstrings lift best with our heels up!  This is also evident when watching the Youtube videos.  You need a dynamic foot.  When pushing down, your heels need to be down, but at the bottom 1/3 rd of the pedal stroke, you need to push your toes down and back behind you, and at the same time lift with your hamstrings to the top 1/3 rd of your pedal stroke.  Then heels back down.  Watch the videos.  Now back to cadence.  Yes, cadence is important, but I am going to tell you to throw it out the window for a while anyway.   Again, “If you build it, they will come!”  Your muscles are not used to working in this way, and they will have a hard time keeping up with this pedal stroke on the back side pull stroke at a high cadence.  So, if you pedal at a high cadence, and stay that way, you will never learn how to be smoothly efficient.  Ever notice how the pro’s upper body just sits static?  That is all pedal stroke.  The higher the efficiency, the more static your body becomes.   But you have to slow it all down to let those muscles build.  Drop your cadence down to the 70 rpm’s.   At this cadence, your muscles can keep up.  Then it will take about a month for these muscles to get used to the pedal stroke, and get engrained with muscle memory.  Then the cadence will come back on it’s own, and the power will come back on it’s own.  Again, if you build it, it will happen.  Here is a great link that backs up this information.  and another with more research links.

So, how do you learn how to pedal your bike efficiently?

Spin Scan by RacreMate.  We have a program that works with our Compu-Trainers that will measure your efficiency.  It will quickly tell us what muscle groups you are using, and where and how much or how little you are using them.  It will show us if one leg is stronger than the other, and by how much.  It also helps with bike fit.  Your bike has to fit well to get a good efficient pedal stroke.  If your saddle is too high, or too low, too far forward, or too far back, then it inhibits your ability to be efficient.  This becomes apparent with the Spin Scan Program.  It draws a graphic representation of your pedal stroke on the computer screen, and itemizes out all the aforementioned data.  If there are any sharp points on the graph, then we know that you are having a problem with transitioning from one muscle group to the next.  That means that something is wrong with your bike fit.  Then we have to look at bike fit to get you the most efficient you can be on your bike.  This process will take about 1 hour, costs $80.00 for the analysis and the bike fit.  That is a total of $80.00 and you get both the fit, and the analysis.  And this will change your cycling forever.  Then any time you want to come back and practice your pedal stroke as muscles develop, it is $10.00 for each session after the first.

Remember, cycling is not about how many watts you can put out, not about how high your cadence is, not about how fast or slow you are, and not about how much you weigh.  Cycling is about having fun, getting out there, improving your health, and accomplishments.  Cycling should be fun, and I want to be the one that helps you find that FUN!  Wether you are a racer, or a recreational rider, build the efficiency, and you will be amazed how everything else happens.  Pedal stroke is the foundation for everything else regardless of what aspect of cycling you enjoy.

We also have CompuTrainer classes as mentioned above.  These classes cost $10.00/ride.  You have to pre-book the day you want to ride, and in these classes we work on pedal stroke efficiency, bike fit, and over all fitness.  Mention this blog and get your first Compu-Trainer ride session free.


Give me a call at Great Basin Bicycles for more information: Rich – 775-825-8258 – Great Basin Bicycles Reno, Nevada