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Vivienne
05-13-2011, 06:32 AM
Not trying to be exclusive or exclusionary in any way, but this is aimed specifically at Keiser folk (as will become obvious)

Cut to the chase.....would this idea work as a profile?

I'm looking for a way to get the idea of the different training effect from different cadence/resistance combos (this thought is from a Tom Scotto post on the ICI/PRO site) without too much explanation, so....

After appropriate warm-up etc. 3 sets of intervals.....

2-3 minute "hill repeats" initially where using a "climbing" cadence of around 70rpm, members find the "gear" that gives them a challenge that's say 7-8 on the 1-10 RPE scale.

Next set of intervals is the same repeats but at a cadence of 80 rpm and reproducing the same power output as set 1

Final set is repeat the above but at a cadence of about 90 rpm.

This isn't the sort of class I usually put together and I can't give it a test drive ahead of time on my Spinner so I'm relying on someone with Keiser Knowledge to let me know if it's workable or not and would illustrate the difference in feel with power output at different cadences. It seems like it would, but it wouldn't be the first good idea I've had that falls flat.

Vivienne

tking
05-13-2011, 08:59 PM
...and would illustrate the difference in feel with power output at different cadences...

Vivienne

I'm not positive this is what you are asking about but here goes.

This may help you with part of your question. I rode an M3 at different RPMs and different gears and recorded the watts at each combination. The graph attached shows the change in watts when you ride an M3 at a set gear and vary the RPM. Point A on the graph shows gear 12, 80 RPM producing 180 watts. Point B shows gear 18, 100 RPM producing 470 watts. The graph shows gears 1, 6, 12, 18 and 24. If you superimpose a Perceived Level of Exertion (PLE) scale on the gears you can then say that, for point A, a PLE of 5 at 80 RPM is equivalent to 180 watts and for Point B, a PLE of 7.5 at 100 RPM is equivalent to 470 watts.

The tricky part about this approach is superimposing the PLE scale on top of the gears. As you know, if you ride a bike at a PLE of 5 (set the gear/resistance and use a set cadence) and then two other athletes ride the same bike at the same settings, one can say it feels like PLE of 3 and the other could say PLE of 8. You also have the characteristics of the bike and where the “base” is. On our M3s, for me, I start feeling resistance at approx. gear 3. I rode another M3 in a different club and I didn’t start feeling resistance until approx. gear 6.

Thanks

Todd S
05-13-2011, 09:26 PM
Physiologically, power is power, and there's really nothing magical about training at unusually high cadences with low resistance or unusually low cadences with high resistance. Metabolically, the whole continuum represents aerobic effort and the corresponding training principles apply. Raising lactate threshold and VO2max is what's important.

The reason things like quadrant analysis ( http://home.trainingpeaks.com/articles/cycling/quadrant-analysis.aspx ) are valuable is that it allows someone to match the neuromuscular demands of competition to training demands. If you're building fitness, power is all that matters. If you're training to compete, there's value in matching the demands of your training to the demands of your event.

(Disclaimer: I have no Keiser "knowledge".)

Vivienne
05-14-2011, 05:08 AM
Thanks guys, I guess the reason why I'm thinking along these lines'd give you an idea what I'm asking.

Even with the cadence meter, there are always a few folk who continue to grind at a heavy resistance, regardless of cues. I guess that's their "prefered" cadence and where they think they're getting a "better" workout or what ever. Doesn't make anyone a bad person but, you can't always get away with doing what you do in a 45 minute IDC class on a bike that doesn't fall over when you're outside on a bike that does.

Well, one of my members approached me after class to ask if I knew anyone she and her husband could hire to teach them how the gears on their new bikes worked. Yippee another convert (I think she was asking if I did that sort of thing....a bit of a hoot!!)

Anyhoo, what I was wanting to convey was how, although you can produce your watts at any cadence/resistance, you build up fatigue much more quickly at the trad IDC "climbing" cadences. This particular member is nice and strong over the length of an IDC "hill" but I fancy leg strength isn't necessarily going to be a limiter for her if she and hubby go out for anything more than an hour or so (I can't be bothered to pump my tires up for anything less) I'm assuming that, since she's gotten into the habit of riding "flats" as if they were hills, it might not be too easy for her to let go of the muscle memory and this is how she'll ride outside.

My husband is way stronger than I am but I drop him like a stone on hills and, because when he gets on the Spinner in the basement he either grinds at a snails pace or weedwhacks so he huffs and puffs (he likes a "good" workout) and although I guess he's somehow fitter than if he didn't do that, it doesn't translate to a fitness that lets us ride comfortably together. In fact, he's a bit of a liability in that he's tried to "show me" once or twice on a hill......started mashing big time, got neck and neck with me, almost pulled ahead and then the legs gave out he pulled over quick and darn near drop kicked me down an embankment. Being still on the learning curve with my bike and still so close to the days when I didn't ride, these incidents are still fresh in my mind in a way that real competent riders probably forgot about decades ago.

Todd....if you've never ridden one of the Keiser bikes, it probably surprises you that my problem is how to get folk to maintian a higher cadence (meaning > 80 rpm) where usually it's getting them to slow down from weedwhacker cadences. The flywheel just doesn't run away with you even at a lightish resistance. You almost couldn't do this as a mixed class on a trad. IDC bike even with a cadenc meter.....it shouldn't be a problem with the Keiser.

It may look as if I'm overthinking this but....a member asked a relevant question and it doesn't seem to me to be too different from hunting down and putting together a new playlist with "songs with words" per a member's request.
Vivienne

Todd S
05-14-2011, 08:05 AM
Two points:

1) Don't get hung up on "strength". Cycling is an aerobic sport that has little to do with strength. When we pedal, we use only a fraction of our available "strength".

2) Self selected optimum cadence will be quite low at low power outputs (no matter how fit the rider). The reason someone untrained doesn't just "pedal like a pro" is because they can't put out the power of a "pro".

All that "pedal fast to stress your aerobic system and pedal slow to stress your muscles" stuff is at best an oversimplification and at worst bu**sh*t. Muscle force is not the only thing that determines fiber recruitment. Speed of contraction is an equally important determinant. It just so happens that substantial fast twitch fiber recruitment happens when you exceed FTP (which shouldn't be a surprise when you think about it). Again, it's power demands that determine fiber recruitment, not cadence. With power measurement at your disposal, cadence should be relegated to its rightful level of importance (somewhere just above choreography).

Todd S
05-14-2011, 08:13 AM
Another thing to keep in mind is system inertia. If the keiser bikes lack the heavy flywheel feel of a Spinner - the preferred natural cadence is going to be lower at higher intensities.

Think of this analogy on a real bike... Same rider, same bike, same power output - say 250 watts. On a hill (where there's low system inertia), the rider will generally chose a relatively low cadence to put out that 250 watts. At the other extreme - say a flat road with a tailwind (a high speed, high system inertia scenario), the same rider on the same bike will probably chose to deliver that same 250 watts at a higher cadence.

liveon2wheels
05-14-2011, 09:30 AM
This isn't the sort of class I usually put together and I can't give it a test drive ahead of time on my Spinner so I'm relying on someone with Keiser Knowledge to let me know if it's workable or not and would illustrate the difference in feel with power output at different cadences. It seems like it would, but it wouldn't be the first good idea I've had that falls flat. Vivienne
I didn't read Tom's post, but I often do drills similar to this to help people get a better feel for their strengths and weaknesses related to the physical requirements of cycling. We know that the higher the cadence, the greater the aerobic emphasis, and the lower the cadence, the greater the muscular emphasis. Therefore, when I am in "training mode" if I am stronger muscularly than I am aerobically (everyone differs on each of these continuums), I have a choice - I can work on improving my weakness, or I can try to maximize my strength. When I am in "racing" or "beating the pants of my husband mode"... er I don't actually have a husband, but for you gals out there :rolleyes:... then I might want to know what the BEST COMBINATION is for me. I call that my "Sweet Spot".

There is a point of combination (cadence and gearing) where I can produce the most power in the most efficient manner. Efficiency is key here especially if the effort is more than a sprint length. It's not just generating power, but it's how do I generate that with the ability to maintain it to the end of my goal (beating my opponent up the hill). If I drop down in cadence, I will have to add some gearing or resistance to maintain the same power. If my heart rate also drops, it is generally a good sign, since I might be able to add a little more cadence to result in higher power with that combination. On the other hand, if my heart rate goes up, and it begins to bring on fatigue more quickly, then that move might end up forcing me to a lower power output before my goal is reached.

I don't know if that answers your question Vivienne, but it is why I do similar drills.

Todd S
05-14-2011, 11:05 AM
I didn't read Tom's post, but I often do drills similar to this to help people get a better feel for their strengths and weaknesses related to the physical requirements of cycling. We know that the higher the cadence, the greater the aerobic emphasis, and the lower the cadence, the greater the muscular emphasis. Therefore, when I am in "training mode" if I am stronger muscularly than I am aerobically (everyone differs on each of these continuums), I have a choice - I can work on improving my weakness, or I can try to maximize my strength. When I am in "racing" or "beating the pants of my husband mode"... er I don't actually have a husband, but for you gals out there :rolleyes:... then I might want to know what the BEST COMBINATION is for me. I call that my "Sweet Spot".

There is a point of combination (cadence and gearing) where I can produce the most power in the most efficient manner. Efficiency is key here especially if the effort is more than a sprint length. It's not just generating power, but it's how do I generate that with the ability to maintain it to the end of my goal (beating my opponent up the hill). If I drop down in cadence, I will have to add some gearing or resistance to maintain the same power. If my heart rate also drops, it is generally a good sign, since I might be able to add a little more cadence to result in higher power with that combination. On the other hand, if my heart rate goes up, and it begins to bring on fatigue more quickly, then that move might end up forcing me to a lower power output before my goal is reached.



Our brains do not guide us to the cadence that minimizes HR at a given sub-max power level. We gravitate towards the cadence that minimizes muscular fatigue. That's why it's important to develop a fine sense of RPE.


The attached document can provide additional insight if this is something anybody really wants to dig into. Table 4 shows how as power output increases, the cadence that minimizes muscular activation also increases. At 100 watts, the average study participant had an aptimum cadence of only 57 rpm. At 400 watts, optimum cadence was almost 100 rpm. Could this explain why Lance was known as an unusually high rpm climber? He didn't climb well because he used a high cadence, he used a high cadence because he climbed so well (put out super high power). (Also, note the large standard errors on Table 4 showing that everybody is different with different muscle fiber makeups).


Final paragraph of the attached:
"In conclusion, we have presented evidence that muscle
activation at a given power output is minimized at a unique
cadence and that unique cadence is higher at higher power
output. We believe this feature of motor control is likely
associated with the force-velocity properties of muscles and
is an important determinant of the metabolic (oxygen uptake)
cost of cycling and also affects the preferred cadence.
The technique of averaging the EMG activity of several
muscles which likely have different volumes may contribute
to a difference between the cadence with minimal apparent
activation, and the cadence with the lowest metabolic cost at
a given power output. Future studies should consider similar
evaluation of two groups of subjects with substantially different
fiber type composition to determine how fiber type
composition affects the relationship between power output
and cadence with minimal activation."

If you have a power meter, it's best not to worry about cadence at all. Know how much power you can sustain for a given time period and let your brain select the cadence that simply feels best. HR can be very misleading as unless you're at VO2max or higher, cardiac output is not your limiter. Metabolic factors and fatigue are.

Vivienne
05-14-2011, 12:24 PM
Our brains do not guide us to the cadence that minimizes HR at a given sub-max power level. We gravitate towards the cadence that minimizes muscular fatigue. That's why it's important to develop a fine sense of RPE....



....If you have a power meter, it's best not to worry about cadence at all. Know how much power you can sustain for a given time period and let your brain select the cadence that simply feels best. HR can be very misleading as unless you're at VO2max or higher, cardiac output is not your limiter. Metabolic factors and fatigue are.


In a way that's the rationale behind the class I'm thinking of putting together. The folks in question in my class don't seem to be finding their own way to a higher cadence.....in fact, they seem determined to stick with what they've always used. The concept of muscle fatigue manifestly isn't foreign to them since they freqently sit up to take a break in the middle of, say, a 5 minute "best effort"

Seems that they don't know which cadence feels "best" because they only ever seem to use the one.

I'm wondering if it's a feature of experience/strength or what. For sure, in Gene's training workshop at the ICI/PRO conference, when we first started off in the morning there was a noticable difference between the cadences that folk were using during the warm up and "unconscious" bits of the programme but when we did the "sweet spot', max. power output that was sustainable, I'd guesstimate that we were all within a few pedal strokes of 90 rpm with no cadence cues from Gene. Doing almost the exact same set of drills in my class doesn't produce the same result.

Vivienne

spinrat
05-17-2011, 09:56 AM
Another thing to keep in mind is system inertia. If the keiser bikes lack the heavy flywheel feel of a Spinner - the preferred natural cadence is going to be lower at higher intensities.

Think of this analogy on a real bike... Same rider, same bike, same power output - say 250 watts. On a hill (where there's low system inertia), the rider will generally chose a relatively low cadence to put out that 250 watts. At the other extreme - say a flat road with a tailwind (a high speed, high system inertia scenario), the same rider on the same bike will probably chose to deliver that same 250 watts at a higher cadence.

I'm going to refrain from any smart ass comments. (It's hard, but I will manage;))
I haven't been on a Spinner in so long. . . when I ride one it's usually at a conference, and I just let go and yield to the ride and the company of 100 committed riders.
Very Good Point. Thanks for the reminder. This one will stay in the front of my brain.

Nshort
05-23-2011, 10:51 PM
I've been teaching on these for a couple months. The common combo I use in coaching the segments is first on cadence, second on intensity, and third having students watch what's happening with watts. The latter 2 are tied together. When I take them to a higher intensity whether it's with more speed or resistance, they should see their watts go up. If they see them the same or lower, I coach how to adjust. Keeping it simple in what to focus on seems to work best especially in a class with a wide spectrum of fitness/cycling levels. In a higher performance class or where I see several serious cyclists in class, I coach more specifically.