iBike power meter

[kempo]

How does one determine LT power?  What is LT power? Does LT have nothing to do with HR?

[Formerly known as easy rider]

Go on Kempo inform me.

 

I thought I had this whole thing sussed.

[kempo]

This is what I am asking the experts.  I am a newby with all this.  Studied Sport Science and have represented SA at Triathlon and Duathlon and can ride a bike reasonably well.

 

Many here have way more theorectical experience than me. So thus I pose those questions.

[Formerly known as easy rider]

Ok Kempo here's my chance to get some free advice and yours to put all of that hard spent money and time studying to good use.

 

(good use= getting a vrot old fart back into good nick!!)

 

My girlfreind and I enjoy our tandem.Have not done any serious riding for a while.

 

My mission is to get myself into good shape with minimum effort and maximum results.

 

So after two thousand or so slow kays.on a "half bike" to get the excess weight off( lost 6 kg,s so far 6kg's to go + 1300 kays).I planned the following.

 

1)Get on a power trainer,with a heart rate monitor.

2) Do a "ramp" test and measure lactate to draw curve(Threshold)

3) Work out workouts according to Joe Friels % of LT (using HR as a guide).

4) Re test every 4 weeks to measure progress.

 

Am I on the right track?

I figure this will give me the best info as to how my body responds to training and allow me to work out what works and what doesn't

 

???????? Help please.

 

 

[Christie]

Great to read a thread without the name calling and mud slinging that has  plagued the hub of late!

 

Thanks for all the info here.My Problem.

 

How does one measure power (individually) on a tandem?

You need 2 SRMs, or 2 Ergomos. (or one SRM & one Ergomo). An easy but expensive solution.

 

Interesting thought, putting power meters on a tandem.

[Man with no name]

christie, you must please show us your power stats from the 'tert some time

[kempo]

Yes thats a good start

Now, nutrition must also come in.  Thats also part of the recipe.  As for the training, what are you training for? You can't just say:  I'm training to get fit.  That won't work. 

 

Then-how much time do you have?  This is very important too.

 

As for the RAMP test-you could to Conconi's test too.

 

As for a power meter on your tandem. going to be difficult don't you think because you and yur gf will have different zones to train in. unless you train seperately and then race on the tandem.

[BikeMax]

 

This is what I am asking the experts.  I am a newby with all this.  Studied Sport Science and have represented SA at Triathlon and Duathlon and can ride a bike reasonably well.

 

Many here have way more theorectical experience than me. So thus I pose those questions.

 

 I thought this was a good explanation;

 

What Is Functional Threshold Power (FTP)?

The

term "threshold" has become synonymous with the word "confusion" in the

minds of many athletes. There are many different words for essentially

the same thing: anaerobic threshold (AT), lactate threshold (LT),

maximal lactate steady state (MLSS), onset of blood lactate (OBLA), and

just plain old "threshold." It seems that there are just as many

possible definitions, with different versions of the concept based on

heart rate, blood lactate, wattage, and so on. As a result, even in

many scientific articles the authors have to present their "own"

definition to clarify what they are talking about.

For more than thirty years, exercise

physiologists have known that the exercise intensity at which lactate

begins to accumulate in a person's blood-that is, his or her functional

lactate threshold (LT)-is a powerful predictor of that person's

endurance performance ability. This is because although an individual's

cardiovascular fitness-that is, his or her maximal oxygen uptake (VO₂max)-sets

the upper limit to his or her rate of aerobic energy production, it is

the individual's metabolic fitness-that is, LT-that determines the

percentage or fraction of this VO₂max that he or she can utilize for any given period of time.

The physiological factors determining functional

lactate threshold are complex, but essentially, blood lactate levels

serve as an indirect marker for biochemical events within exercising

muscle. More specifically, a person's LT reflects the ability of his or

her muscles to match energy supply to energy demand, which in turn

determines the fuel "mix" (i.e., carbohydrate versus fat) used and the

development of muscle fatigue. Consequently, functional lactate

threshold-especially when expressed in terms of power output, which

also takes into account cycling efficiency-is the single most important

physiological determinant of performance in events ranging from

something as short as a 3 km pursuit to a stage race lasting as long as

three weeks. Just as important, because the effort that is experienced

by an athlete when exercising at any given intensity is dependent upon

his or her power output relative to power at LT, this parameter

provides a physiologically sound basis around which to design any power

meter-based training program. Functional threshold power is the highest

power that a rider can maintain in a quasi-steady state without

fatiguing for approximately one hour. When power exceeds FTP, fatigue

will occur much sooner, whereas power just below FTP can be maintained

considerably longer.

 

So, how do you go about determining your

functional threshold power? One way is via laboratory testing with

invasive blood sampling, but few people have access to such testing on

a regular basis. In addition, power at LT as determined in this manner

is often significantly below what athletes and coaches tend to think of

as a "threshold." A more convenient and possibly more accurate way of

determining your FTP is to simply rely on data collected using your

power meter in the field. There are a number of different ways to do

this, each of which has its advantages and disadvantages, but all of

which provide very similar estimates of threshold power.

With

all these different ways to test your FTP, you may wonder which one to

start with. We believe that the best way to begin is to just go out and

do a ride specifically designed to find your threshold, such as the one

described in the next section. This is without a doubt the first big

step in your new adventure in training with power.

 

[BikeMax]

 

Great to read a thread without the name calling and mud slinging that has  plagued the hub of late!

 

Thanks for all the info here.My Problem.

 

How does one measure power (individually) on a tandem?

 

That would definately lead to a divorce...

 

If you ride as a pair then the combined output (and improvement) is what matters.

 

[BikeMax]

 

Ok Kempo here's my chance to get some free advice and yours to put all of that hard spent money and time studying to good use.

 

(good use= getting a vrot old fart back into good nick!!)

 

My girlfreind and I enjoy our tandem.Have not done any serious riding for a while.

 

My mission is to get myself into good shape with minimum effort and maximum results.

 

So after two thousand or so slow kays.on a "half bike" to get the excess weight off( lost 6 kg' date='s so far 6kg's to go + 1300 kays).I planned the following.

 

1)Get on a power trainer,with a heart rate monitor.

2) Do a "ramp" test and measure lactate to draw curve(Threshold)

3) Work out workouts according to Joe Friels % of LT (using HR as a guide).

4) Re test every 4 weeks to measure progress.

 

Am I on the right track?

I figure this will give me the best info as to how my body responds to training and allow me to work out what works and what doesn't

 

???????? Help please.

 

 

[/quote']

 

Why not keep it simple;

 

1. Ride a max 20 min effort - if you have power and are going to train with power then measure the average. If you are going to use HR then do likewise. Be sure to measure distance travelled on this test so as to allow frequent measurment of progress (I would suggest a 20 min steady climb if you have one)

 

2. Estimate FTP HR - probably pretty similar to the 20 min HR but maybe slightly less as the duration is now 60 mins

 

3. Use Coggans schema to calculate guideline training zones - and then be sure to use these in conjunction with RPE

 

4. Train effectively in the right zones

 

5. Retest every 6 weeks or so

 

Good luck.

 

[Formerly known as easy rider]

Kempo the first real goal for this year is to get in a good 94.7.

Nutrition for the moment is keeping protein up,no starchy carbs, other veg up to get rid of fat(its working well!!)

I think BikeMax has a point about the power cranks on a tandem.Its combined output that matters.If I link workouts to HR (in the beggining stages of training),to gather data (as each tandem partner can work in different zones) and then worry about power output later,I reckon I can come up with a program that works for both of us.

I have seen that time spent riding together is all important especially when it comes to climbing on a tandem.You can end up "fighting" each other on hills!!So its best to train together as much as possible.

 

Maybe a few individually incompatible wokouts on "half" bikes.

 

Thanks for all the info BikeMax.

[BikeMax]

 

Kempo the first real goal for this year is to get in a good 94.7.

Nutrition for the moment is keeping protein up' date='no starchy carbs, other veg up to get rid of fat(its working well!!)

I think BikeMax has a point about the power cranks on a tandem.Its combined output that matters.If I link workouts to HR (in the beggining stages of training),to gather data (as each tandem partner can work in different zones) and then worry about power output later,I reckon I can come up with a program that works for both of us.

I have seen that time spent riding together is all important especially when it comes to climbing on a tandem.You can end up "fighting" each other on hills!!So its best to train together as much as possible.

 

Maybe a few individually incompatible wokouts on "half" bikes.

 

Thanks for all the info BikeMax.

[/quote']

 

Once you get both of you to a decent level of fitness then another big factor on  a racing tandem is how to measure the effort that you are both putting out - in other words to avoid one of you killing themselves while the other is cruising.

 

Either some sort of RPE - 1 to 10 score that you communicate, or maybe HR %age ( I knew there was a use for it )

 

[kempo]

Peter-recently did a VO2max test-peak power 458. Threshold 340.  Any good in your view?

[Windbreaker]

 

 

 

 

Optimal cadence has been shown to be the cadence at which you develop

the most power given the duration you are riding. Your cadence will

have dropped because you find it easier to develop more power at this

cadence.

Or it is because I did most of my L4 intervals on hills and not enough on flats?

 

Why do we need to know what your HR is doing at FTP -  if you

can ride at that power for the necessary duration then surely that is

sufficient information ? (As we know already' date=' HR at FTP may be

influenced by many other things and so we cannot make a meaningful

comparison)[/quote'] Well if you agree that riding at different cadences does impact on heart rate and if it is accepted that you can't maintain a HR that is above a certain value then there should be a "sweet point" where both power output and heart rate are matched?

 

I would suggest that you get dropped' date=' not because of

the cadence you are racing at but because you are unable to make the

necessary power over the duration you need - your increased cadence may

simply be an attempt to output more power.[/quote'] But I know that I can maintain, for example, 285w on a 20min climb, but I sure as hell can't do that on the flat in a race for a full 20min (even when it is in the early stages).

 

For the same I tend to do all of my L4 intervals on a hill - because it's easier and I wonder if it is a self fulfilling cycle. (when I am training that is)

 

The basic premise that I am considering is that if HR is a measure of physiological response (again assuming that you can account for the other influencing factors) and power is an accurate measure of load and cadence is the actual mechanism then you should be able to match the three measurables for max efficiency.

 

On their own though I agree that power is the most reliable and specific measure.

 

 

 

Windbreaker2007-06-12 06:33:30

[BikeMax]

 

Peter-recently did a VO2max test-peak power 458. Threshold 340.  Any good in your view?

 

What is your weight ?

 

[kempo]

79-slightly heavy for me at this time. but jo'burg season still 13/14 weeks aways so not too worried.  goal weight is usually 74/5.