cadence vs power and comfort

Satish Punna

 Hi all.  I'm relatively new to cycling and using power.  I have a powertap.  I just finished todays preason 90 minute easy ride on my trainer and noticed something that I found unusual and I wonder what if any implications it has on my training.  Most of the ride I kept the power at 65-70% of FTP in whatever gear I needed to keep cadence above 90 (was usually 93-95). I was in the aero bars for probably 98% of the time.  The last 10 minutes I switched it up and lowered cadence to 77-80, still in aero.  I found that power immediately went up to 75-76% of FTP and my heart rate dropped by 6-7 bpm.  I find this surprising since I would expect hr to be steadily climbing toward the end of a 90 minute effort due to cardiac creep etc.  Moreover, my saddle and feet also felt more comfortable at the lower cadence.  So- is 80 rpm some kind of sweet spot? I was under the understanding that one should strive for 90+ cadence.  Is 77-80 the cadence I should target for future workouts, and will doing this have any detrimental effects? Any input is appreciated- thanks!

Mike Weinmann

satish -- i'm in the same boat as you -- new to power and also seem to be able to generate power much more easily at a lower cadence. during this week's interval sessions, i was using a lower cadence / higher gear to get the tougher intervals done.

i find it somewhat easier to get my cadence up when outdoors (for example, during this morning's 90 min ride), but it feels like my "natural cadence" is well below 90.

interested to hear the EN vets experience on this

Dino Sarti

Others with more experience will chime in, but I have fairly similar results to report. Spinning the pedals above 90 for me just seems to be more aerobic. A lower gear with lower cadence generally allows me to produce more power longer than spinning. Remember power is torque x cadence. Driving more of one will create more watts if the other is constant. However, I do find if I spin more cadence, my legs feel less heavy.

The issue people love to raise is running well off the bike. The idea is a higher cadence better matching your run cadence will allow you to run better. I don't know. My run cadence is usually on the low side at 88-90 as well.

Peter Greagg

FWIW, I find FTP intervals "easier" at 88, whereas my APB rides in Z3 appear easier at 93.
Strangely, my VO2 max intervals I do around 98.

benvanmarcke

Power is torque x velocity when measured on a hub so if you measure it using e.g. a powertap, cadence doesn't come into play.

I've found my optimal cadence depends on the terrain. If my usual cruising rpm is 96~98, my best olympic distance triathlons gave me average rpm of 103~106 (with powers in the 330~360 watts range. If I would be racing without my powermeter (or without looking at it) I can sense if I'm having a good day or not based on my cadence.

For climbing it's a bit different, and cadence is best around 90rpm. If I go faster my heart rate will start to go up and I'll have difficulty breathing (it becomes an anaerobic effort).

I'd suspect everybody's optimal cadence is different and determined by muscle type and slow twitch / fast twitch fiber ratio.

Dino Sarti

@Ben - Great correction!

I couldn't hit the those cadence numbers of your without gassing myself. I am generally 85-90 riding steady and climbing 75-85, sometimes much less when I run out of cogs.... :0)

GMAN 19030

Current thread on ST about the cadence debate: http://forum.slowtwitch.com/gforum.cgi?post=4237427 ;

Satish Punna

Thanks for the replies. I spent a bit of time reading around the issue this weekend (not sure how that fits the concept of ROI, lol) and the answer seems to be....there is no answer. Some say cadence is personal preference, while others say everyone should do this or that. There is apparently a study that shows running performance off the bike is improved after high cadence cycling, but there is another study that refutes this. Theoretically higher cadence uses more fast twitch fibres that *should* preserve glycogen and lead to less fatigue and better performance on the run and also may result in better neuromuscular 'adaptation' when one has to run off the bike, but there are many, including several pros, that ride with low cadence and seem to do just fine. SO, it seems that cadence, like many other things may come down to personal preference. But what was interesting to me was that my CV system was seemingly less stressed at higher power output when I used a lower cadence (not super-low, but lower). That leads to the question which is more important in triathlon- conserving the CV energy system or the muscular energy system (assuming you can actually separate out the two). I think the only way I will find out how what this will affect ME is to try several brick workouts after using different cadences to try to peg what cadence leads to the best run for me (and YMMV). Maybe continuously striving for the highest cadence possible isn't a 'one size fits all' endeavour?

GMAN 19030

I mentioned this in the ST thread but I ride in the 82-86 rpm range. Anything 90+ wears me out if done for an extended period of time. I'm just not a "spinner" and am more of a power rider. I will ride the last 5% of the ride at 90+ to spin the legs out and get them ready for the run.

Dino Sarti

Thanks for that, Bob. I am in the same boat, but wasted a lot of time this Summer chasing numbers in the high 90's.....

Dave Campbell

@ Satish, yes, do your test and see for yourself. Here is my experience. Been riding and training with a power meter since 2004. I notice this mostly on the trainer because it is more stable than open road. Say I'm doing a 20' FTP interval. I like about 85-90 RPM's. My self selected sweet spot. So, I start off there, ride a couple minutes, then shift 1 gear easier to hit 95-100 rpm's. I hold the power the same. My hr will go up a few( maybe 4-5 beats), legs feel fine. Then I shift down a couple gears harder so cadence is now 70-75. Keep power the same, Hr will drop maybe 4-5 beats, but legs begin to burn. What I see is that working the CV system recovery is pretty quick. Sometimes I drop down to 60rpm's and the muscles will begin to hurt. CV is fine. But this muscular fatigue does not go away nearly as fast as a Hr recovery. For me, I postpone muscular fatigue as long as possible favoring a higher cadence and Hr. And since we want to run at 85-90 rpm, just makes sense to ride there. The only time I'm riding at low rpm's is in the mountains when I'm out of gears and have no other choice. Been up some hour long climbs at 60 rpm's at FTP and hr has never been the issue, but man did the legs hurt. Would not want to run after that. So, test your theory out and let us know what you discover.

ezellrh

Satish, lots of good advice, with the bottom line of 'go discover what works for you' being dead on. I seem to be on the other end from what most people that have replied. Indoors (during the OS), I feel like I'm grinding at anything less than 90 rpms. I started riding around 2002, when it was all 'LA rides at high rpms, so we must do that', so that's I'm used to. My comfy spot is ~95, faster when doing VO2 work. Bottom line, find what works for you, remembering you have to run afterward. Good luck!

mgraffeo

Take RPE out of this, and there absolutely is an answer. 30 years of research has shown that we are more efficient pedaling at cadences closer to 60 RPM. So, if you're pedaling at ~90, going lower should be more efficient (ie. higher power at lower HR).

The fuzziness in all of this comes when you try to understand why we don't pedal at that lower HR in long distance endurance events. Short answer is that you can get power through high RPM, low muscular force, or high muscular force, low RPM (and of course the spectrum in between). Lower cadence, higher muscular force might conserve heart beats, but causes more muscular damage, which is undesirable both for training and for stage racing or triathlon.

There are definitely TT specialists who TT in the 70's for these reasons. No run afterwards, plenty of opportunity to recover.

Al Truscott

Posted By Satish Punna on 22 Oct 2012 07:21 AM

...That leads to the question which is more important in triathlon- conserving the CV energy system or the muscular energy system (assuming you can actually separate out the two)...

simple answer ... At the speeds we race HIM and IM, our muscles will wear out long before our heart and consequent abilityntomdeliver oxygen to muscles ever do

Satish Punna

 Thanks for the input everybody ! 

William Jenks

Graffeo is 100% right. As is Al.