rclouviere

I’ve recently lowered my cadence and it seems to have increased my power output (watts). Does an increase in watts automatically mean increase in speed?

DaveSSS 

Just the opposite. Power equals torque times cadence. More power with lower cadence requires more torque.

tomato coupe

All else being equal, it should.

Iride01 

For any speed and time period that you maintain that speed, your watts on the same bike and same conditions will be the same at low cadence or high cadence. The big question is at what rpm can you produce the power comfortably for the time required at that speed.

datlas 

This.

choddo

Depends if you can maintain the same, or perhaps even better, position and therefore aero profile at that higher torque and as others have said, is it comfortable enough to sustain for long enough to make the speed increase stick.

rclouviere

Thanks. It actually feels better and, feels better the more i do it.

TMonk

the general consensus is that higher rpms are better since it stresses the cardiovascular system over the musculature. your heart/lungs can go longer than your legs.

but that doesn't mean its true for everyone. there are plenty of very experienced riders and racers who prefer a lower cadence. as with everything else, YMMV

TMonk

all the zwift riding ive been doing over the last several years (esp lately) has lowered my cadence for some reason. I need to get back out on the track - that brings things right back up

datlas 

I think most well-designed studies conclude that self-selected cadence is best.

PeteHski

I think that may be true, but I think cadence is also trainable to some extent. I try to work on producing power across a wide cadence range from as low as 50 rpm to 100+ rpm and I’ve found that my “preferred” cadence has increased slightly over the years by around 5-10 rpm.

eduskator

Lower cadence + higher torque or higher cadence + lower torque, will equal the same power.

There's usually a balance and your body can find it easily by itself. Cadence is trainable as other said - for marginal gains - if that's what you're looking for.

RChung

Your "preferred" cadence may have increased, but I'm betting so too have your "preferred" torque and "preferred" wattage output.

With training, all three increase but before the wider use of power meters, the only thing that most of us could "see" was cadence. I suspect that's why so many people focus on cadence--it's easy to see.

PeteHski

Yes and I also prefer to use a higher cadence at higher power levels, which I think is fairly typical. So I might cruise along at 80 rpm at endurance power, increase to 85 rpm at FTP and 90 rpm at VO2 max power and 100 rpm for sprints. So perhaps I have more of a preferred torque level. I'm not that keen on spinning at low power or grinding at high power.

Hermes

How about ones preferred speed? The current trend is bigger gears and lower cadence are faster. One may not like that and think that the best cadence is self selected - trust your inner god or goddess. However both track and road racers at the Team USA and UCI pro levels are using bigger gears and lower cadence to generate more speed.

And I guess the theory is all the energy used to make the legs go around faster results in slower speeds and winning and losing decided by very small speed differences. And training with bigger gears just makes one stronger with the ability to generate more speed when it matters.

terrymorse 

Yeah, that sounds like you have a fixed "preferred torque" level.

I think I gravitate towards a preferred power level, but it's grade dependent. I have no trouble maintaining power uphill, but it takes lots of concentration to keep the same power going on flat terrain. Shifting to a higher gear doesn't seem to make a difference -- the flat road power just doesn't seem to be there. Maybe I'm just "neuro-muscular" adapted to riding uphill.

PeteHski

For me power level is dictated entirely by the type of ride and my ability to generate it! All I can say is that I can generate more power at a higher cadence, but for less time. But for any specific steady state power I will have a “preferred” cadence and that preferred cadence tends to increase with power.

But then sometimes I like to vary my cadence at the same power level. Especially when riding on the flat for a long time at tempo. I don’t like riding a fixed cadence for a prolonged time.

So I see cadence as quite a dynamic variable.

genejockey 

I've observed that the cadence I settle into automatically on Zwift depends on whether I'm riding solo or in a group - either a group ride or a race. Freeriding, I'll settle in at around 95 - much the same as on the road. In group rides and races, I tend to do more like 85-90. I'm pretty sure this is because the lower cadence works best for all the micro surges I do to maintain position in groups. Spinning at 85, if I need to increase my speed just a touch, I can spin up a few rpm easily, whereas if I'm at 95 it's not as easy to spin up to a higher cadence.

It also feels like every race or group ride I'm in puts me at the speed where there's a gap in the cassette, so my choice is 85 or 100 rpm.

PeteHski

That’s an interesting point. When I ride in a Zwift group (or in a road group) my cadence is all over the place and I will often shuffle back and forth between adjacent gears. You often see the same thing happening in the pro peloton when they are bunched up.

tomato coupe

Except the power levels span a much wider range than the cadences, so there's not really a preferred torque, as it also spans a wide range.

terrymorse 

OK, so it's more of a "tendency to prefer a narrow range of torque".

Let's look at PeteHski's numbers...

Power (roughly):
Endurance -- 70%
LT -- 100%
VO2max -- 110%

Preferred power/cadence ("torque"):
Endurance -- 74.4%
LT -- 100%
VO2max -- 104%

So there's a range of torques, but they are narrower than the range of cadences. If we go with the idea that cadence is self-selected to limit muscle fatigue, it makes sense that we select lower torque for endurance efforts, higher torques for shorter and harder efforts.

PeteHski

Yes, that’s true. My preferred cadence range is really only about 80-90 rpm across much of my power range. I’m usually at about 85 rpm at FTP. But I don’t strictly adhere to these “preferred” cadences. I also tend to favour a slightly lower cadence when climbing, which again I think is quite common with low crank inertia.

tomato coupe

I don't even think it's a narrow range of torque. If it was, you'd see people double or triple their cadence when doing hard efforts. I think it's really a person's preferred cadence range that drives everything.

RChung

Hmmm. I don't. I think riders sometimes prefer to keep their cadence in roughly the same range while modulating power with torque, sometimes they prefer to keep their torque roughly around the same while modulating their cadence, sometimes they change both, in varying amounts, depending on the conditions of the ride.

Here's the image I've been keeping in my brain for many years; the two dotted lines show two different power levels, in this case 200 and 300 watts. Suppose I was somewhere along the 200 watt line. There are an infinite number of combinations of cadence and torque that will get me to 200 watts, but suppose I'm at the red dot. Suppose I want to increase my power to 300 watts. There are also an infinite number of combinations of cadence and torque that will get me to 300. I've drawn just 3 "expansion paths" that I could use to get to 300 watts: one is mostly vertical (that is, I keep my cadence about the same and increase my crank torque), one is mostly horizontal (that is, I keep my crank torque about the same and increase my cadence), and one that goes off diagonally (where I increase both my cadence and crank torque).

I contend that the terrain, the acceleration, the wind, and (critically) where the red dot currently is (that is, what my current cadence and torque are) all influence the power expansion path that is actually chosen. In some (many?) cases the PEP can be backward bending so my cadence drops while my crank torque goes way up; in other cases, I spin way up but drop my crank torque.




For me, when I climb hills, I often drop my cadence and increase my torque; when I am accelerating on the flat, I often increase my cadence but decrease my torque. I'm not sure what others do but it would surprise me if I were unique.

choddo

And whether you can be arsed to shift chainring

e.g. on Sunday morning 80km of 85km in, with a hangover, soaking wet, covered in spray grime as well as blood from a 30km nosebleed that came from nowhere and wouldn’t stop, I picked the vertical (even up and 45° left) line for the last couple of short inclines to avoid changing into the small ring. The dotted lines in this example were about 300 and 450W and all I could think about was getting home to a hot shower 😆