average wattage - average watt

I don't understand your post. Are you talking about a simulated hilly ride on a fancy indoor trainer like a computrainer? Or are you talking about different rides on different days? Why were you unable to switch to average HR? If you're just trying to perform a ride on a hilly course at a specific power output, why worry about HR? 😕

it was one ride on a taxc Fortius (something like a computrainer).

I wanted to ride at a constant 285 watt . I couldn't keep the wattage at 285 exactly. So I started looking at the average power output during the ride.

Afterwards It seemed that although I trained on wattage I could have achieved the same on an average heartrate.

That's why I'm going to do the same ride but then on an average heartrate to see how those 2 rides compare.

I'm trying to convince myself on training by power but don't seem to find the extra that it can give me

I'm sure there will be others who can help you better with this, but using power you are much more exacting with your intervals. On long intervals HR isn't too bad, but especially indoors i find that if i'm doing 2x20's my HR might not get to a point and just stick there, it is climbing most of the time during the 20 minute interval, if i used avg HR then i would probably start to hard and fade at the end. Power is great for short intervals because your HR lags behind, power is instantaneous. By the way your power is going to fluctuate huge on a rolling ride, if the ride was constant grade you would have a much easier time holding a specific power.

Ok, I understand now. For typical rides on rolling terrain, it's not really recommended to try to keep your power at a fixed wattage -- it'll go high as you climb, and go low as you descend. So, if you're just shooting for an average power level, then why not just shoot for an average HR?

In fact, many power users still ride by HR on their longer, lower intensity rides since it provides a rough gauge of intensity that's not so affected by the variations in terrain.

stevevinck said:

I'm trying to convince myself on training by power but don't seem to find the extra that it can give me

The extra benefit is in the insight the power data provides to your overall training and improvement, rather than as a more precise pacing tool (although it's better for that, too, in the case of shorter, harder intervals).

stevevinck said:

I'm trying to convince myself on training by power but don't seem to find the extra that it can give me

Well, here's a data point that may help you see the value of training with a PM. On a recent ride (a long hillclimb), I had the following averages of power and HR. The observations were 1 mile segments at about the same speed, therefore the durations were similar.
Watts HR
245w 83.0%
232w 83.6%
228w 83.0%
219w 83.6%
210w 82.4%
199w 82.4%

Now, that's a pretty big swing in power (~23%) with almost a negligible change in HR (1.5%). And, that's one ride on the same day. For observations made on different days, I would expect even larger differences. So, if I managed my intensity level by HR, I would be wandering all over the map. Instead, I manage my intensity level by power, so I can choose where I want to be. Your HR may track more closely to power, but I wouldn't just assume it so.

RapDaddyo said:

Well, here's a data point that may help you see the value of training with a PM. On a recent ride (a long hillclimb), I had the following averages of power and HR. The observations were 1 mile segments at about the same speed, therefore the durations were similar.
Watts HR
245w 83.0%
232w 83.6%
228w 83.0%
219w 83.6%
210w 82.4%
199w 82.4%

Now, that's a pretty big swing in power (~23%) with almost a negligible change in HR (1.5%). And, that's one ride on the same day. For observations made on different days, I would expect even larger differences. So, if I managed my intensity level by HR, I would be wandering all over the map. Instead, I manage my intensity level by power, so I can choose where I want to be. Your HR may track more closely to power, but I wouldn't just assume it so.

These are the numbers that I search !! Amazing indead . maybe tomorrow or otherwise sunday I'll perform the same ride again on heart rate and compare the 2 datas

But still isn't the hart the motor we're trying to train ? and therefore it seems so logic to concentrate at those readings.

stevevinck said:

But still isn't the hart the motor we're trying to train ? and therefore it seems so logic to concentrate at those readings.

Your heart is just a "slave" to your muscles, and while your cardiovascular fitness sets the upper limit to your sustained aerobic power output, it is your muscular metabolic fitness that determines what fraction of that maximum you can utilize. Morever, even you wish to focus on training your heart, heart rate only tells you part of the picture...for example, if you do all of your training in a hot, humid environment, your average heart rate during training will be significantly increased, but you won't gain any additional training benefit as a result.

stevevinck said:

But still isn't the hart the motor we're trying to train ? and therefore it seems so logic to concentrate at those readings.

Nope. In most cases the leg muscles will stop pushing long before the heart gives out. In fact, your leg muscles need to be fairly fit just to be able to give the heart a good workout.

frenchyge said:

The extra benefit is in the insight the power data provides to your overall training and improvement, rather than as a more precise pacing tool (although it's better for that, too, in the case of shorter, harder intervals).

Or as I like to put it: it's not about training by power, it's about training with power (data). The misconception that stevevinck is laboring under - which is common one, especially those young enough to have been "raised on" heart rate monitors - is that the benefit comes from training by power. There can be some, but that's barely scratching the surface of what a powermeter can do for you (as you indicate).

stevevinck said:

But still isn't the hart the motor we're trying to train ? and therefore it seems so logic to concentrate at those readings.

Actually, the heart is only one of many responses to high-intensity endurance exercise and is not the primary limiter to performance. In fact, the heart responds in two ways to increased intensity -- increased heart rate and increased stroke volume. Stroke volume is the amount of blood pumped with each beat. Both respond over a similar range, but not necessarily in lock step. For example, at rest an athlete might have a HR of 60bpm and stroke volume of 80ml/beat. At or near his endurance limit, the athlete might have a HR of, say, 3x his resting pulse (180bpm) and stroke volume of, say, 2.5x his resting SV (200ml/beat). So, stroke volume contributes almost as much to the athlete's increased volume of blood pumped as does heart rate. And, they don't necessarily respond in unison to increased demands. The only thing you are measuring with a HR monitor is HR, not SV. So, you are measuring only ~1/2 of the cardio response. So, no, your cardio system (heart) isn't the only "motor" you are trying to train and is arguably not even the most important "motor." Second, measuring HR is measuring only half the cardio response. Apologies to all the HRM devotees.

just to let you know my testing result

09 march : 126,5 avg.heartrate 225,6 avg.watt
11 march : 125,8 avg.heartrate 232,6
11 march after training of 100 km redid course 1 : 125,6 avg hr 175,8 avg watt

So now I'm convinced 🙂 and have to start saving 🙁

[font=Century Gothic]Hi Steve[/font]

[font=Century Gothic]i guess I'm a devote of the HRM having been 'young enough' to have been training with one for the last 20 or so years. But I would for sure recommend that you get a power-meter for the road if you can afford it. The last months Ive not been using my HRM & with experience enough you 'can' get by with a powermeter & be able to do a good long hard ride without getting into trouble. I will put the HRM back on when things get serious & I start racing again as its still very useful info (especially when things go bad). [/font]
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[font=Century Gothic]I think when you use a HRM to train the engine your thinking not of training the heart muscle but rather your circulation & Blood flow. Riding for long periods in a aerobic HR zone is for me the real use for a HRM. Its a good way of visualizing the overall stress you are under, Power can sometimes be hard to pace with in undulating terrain. HR drift indicates that stress is present which is useful to know if you did not manage to finish that interval or blew towards the end of a ride or race. Approaching the end of a long hard ride with not enough drink/kilometers done in training/or cooling will cause HR to drift upwards, often in line with the feeling of stress/pain. It hurts more at the end of a ride & HR drift reflects this. You have a choice to either hurt more & keep power steady or keep HR steady & reduce the power. One option will cause you to eventually stop the ride where the other will result in the last part of the ride being perhaps not as effective as the first part.[/font]
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[font=Century Gothic] I find also simply knowing if HR was responsive of sluggish compared to the effort (power output) is a great way of knowing if I was riding with fatigue. Often fatigue is very hard to feel but the knowledge that LT HR is say for example 10bpm lower then normal gives you at least an idea that your not firing with all your cylinders. That with rest enough I can do better. That the under lying condition is better then the power produced suggests.[/font]
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[font=Century Gothic]You can also take your blood pressure & measure the difference between systolic & Diastolic. This will help you get an idea of the volume of blood you have to play with when you also consider HR. Its a personal thing though so you will need to take it regular for a few months & see what your magic numbers are (for me they were surprisingly high 140/65 with about a 40bpm RHR. [/font]
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[font=Century Gothic]There are various tests you can do with HR off the bike to determine if its going to be worth betting on your self at the local kermis. The simplest is to just lay down & measure the standard deviation (difference in duration between each heart beat) of your resting HR. When under stress a fit riders HR will be very level & rhythmic. When totally fresh & ready to race his HR will change as his lung muscles contract to breath. This race ready responsiveness is also visible out on the bike when you have a 'good' day. HR will drop instantly & rise really fast when the 'watts' are produced.[/font]
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[font=Century Gothic]I think the days when the HRM was the best tool for pacing are now gone as power is direct & form (or lack of it in my case) is immediately obvious as soon as you make a flat out effort. But the HRM still has a use, at least for those that understand it a bit. [/font]