Power Cranks Review

Jump4Joy19

I first tried out a set of Power Cranks at the Seattle Bike Expo a few years ago, and I knew then that they would be an incredibly useful tool to have, but they're pretty much out of my price range until my kids get through college . If you're not familiar with them, they're a set of cranks that let each pedal go around independently of the other, forcing you into pedaling a complete circle with each pedal stroke.

This year I got an opportunity to borrow some from a friend, so a few weeks ago I threw them on my tri bike and set it up on the trainer, ready to give them a try. To my great embarassment, I lasted 3.5 minutes before my legs screamed "Uncle!". That was it. I could've easily gone 3 hours on my regular cranks, but it was 3 minutes on these torture devices. My heart rate shot through the roof, yet my "normal" biking muscles hadn't even gotten warmed up yet. It's all the little muscles that you don't typically use when biking (since you can just hammer with the quads and not worry about it) that were fatiguing so quickly. 

Two days later I managed 2 x 5' intervals on the cranks. Then I had to switch my hubby's road bike onto the trainer for the rest of my workout. By the next week, I managed 2 x 12' on the cranks, but it was still taking all of my concentration to make my legs go around in a coordinated fashion. As I got tired toward the end, I actually had to just watch my feet the whole time.

By week 3, I was finally getting a handle on riding on these things and was up to a whole hour in one shot. But I still had no power, that was just basically concentrating all of my mental and physical energy on making the pedals go around. At the end of an hour bike session, my normal "biking" muscles hardly felt like I'd done anything at all, but my heartrate had been on the high end and all kinds of odd parts in my legs and glutes were sore.

In week 4, I could vary the gears a bit and take it up a notch for brief periods of time. I decided to ditch the road bike and try to just ride my workouts on the Power Cranks. The only exception was my FTP test, which I did on the road bike. No way could I power through something like that on the Power Cranks.

Now I'm into week 5 on the cranks, and for the first time I did a workout with intervals and felt like I could push hard on the intervals on the cranks. Unfortunately, I was riding with a Sufferfest video and the video said to stand up and crank up the hill, which I attempted to do. Let's just say I'm not capable of standing up on the Power Cranks yet. I almost fell off my bike as both feet came to a full-stop at the bottom of the pedal stroke. So there's yet another skill to master on these things, and I am nowhere near ready to ride them outside yet.

I'll post more as I experience it, but so far I have to say that I'm sold on the usefulness of the Power Cranks. Clearly I am experiencing a lot of muscle adaptation in the month or so that I've been riding on them, and I feel like it's also helping my running as I can feel my glutes and upper hamstrings engaging more in my running stride.

Bomber

Will be interesting to see how it affects your FTP.
Please keep us posted.

Paul Hough

Robin - your progression sounds like you are sticking with it and making progress. I've read that standing up on them is the true test of mastery. I think there was at least one pro who used powercranks in an actual Ironman and won. I guess you know you've arrived when you decide to race them as your preferred crank! Please report back with your 2012 performances and how they stack up to previous, as adjusted for any other changes you make. Good luck!

Jump4Joy19

One of the things that would make buying a new pair of Power Cranks even more appealing is that they are now completely adjustable in crank length, with holes drilled down the crank. So you can spend some time playing with optimal crank length and positioning, without having to go buy a half dozen sets of cranks.

I don't think I'd ever race on them though, these suckers are heavy!

Cary Blanco

Interesting stuff, thanks for sharing.

jetskr

Hey Robin,

How has training with these affected how you ride normal cranks? Have you noticed any difference?

Matt Samojeden

Robin, I share your view that the PCs sure help the glutes and hammy on the run. Also my hip flexes are much stronger. That being said I think the benefit of power crank workouts help the run much more than the bike. I think the marketing spin on the PC website now emphasizes this point.

Jeff, I have always had a reasonably good circular spin on the bike. I dont notice much difference when I ride normal cranks.

Jump4Joy19

@Jeff, the last time I was on the Computrainer on regular cranks, I noticed that if I concentrated on pretending I was riding the Power Cranks, in other words pedaling through the entire stroke, I gained about 15 - 20 watts pretty much instantly. So I think that for me, when my muscles fully adapt to the motion and have endurance and power using that motion, I will pick up some power gains.

 

@Matt, I can really see that now. In fact, I was marveling that this week's track workout was even faster than last weeks, even though my legs felt absolutely baked from the Power Crank intervals and from several long swims. I think I am seeing some pretty rapid gains in my running form that aren't 100% attributable to the OS workouts. I can actually feel my legs engaging better on the back half of each stride. Heaven knows, my run has always been my biggest limiter, so any speed I can pick up there will be truly appreciated.

Coach Rich

Here is my quick take on Powercranks and if you've been in the triathlon internet world for a while you can understand when I say I'm glad this is a close forum, for fear of He Who Shall Not Be Named showing up :

• The bike goes faster because we put more power to the rear wheel. Period. Not because it feels hard, not because my hip flexors are shelled, but because my engine is putting more power to the rear wheel.
• Many have had the observation that during this adaptive phase (potentially very long), their legs rest on the downstroke because they are so worked on the upstroke. The net is a loss of power = body is doing less work = potential decreased fitness.
• The prime movers/muscles in the legs are engineered to push, jump, and generally direct force downward. The hip flexor is a relatively small muscle. Why spend so much effort taking the focus away from the muscles designed to do the work and developing a relatively small muscle, especially when learning to do so decreases the work load applied to these primary muscles? See #2 bullet.
• If you get good with PC's, or simply focus on applying more power across the full circle of your pedal stroke (rolling the barrel from 11-2p, scraping mud from 5-8p), yes, you'll likely see a power increase. BUT, energy is not created out of nothing. This power/work didn't magically appear. You are doing more work, largely as a result of applying more muscles/focus across the entire circle of the pedal stroke. However, the ability to sustain that higher workload is a fitness issue. Again, nothing is free, there are no free watts. They had to come from somewhere.
• I've heard they do improve people's running, especially those with injuries who can't run. Fine...market PC's as a running aid first, cycling aid second.
• Finally, I tried a pair about 9yrs ago under a special program that He Who Shall Not Be Named was offering to coaches. For me...they just sucked to ride. Took the fun completely out of riding a bike.

My net is that a powermeter is a MUCH better investment than PC's.

Jump4Joy19

Interesting stuff CoachR. Some thoughts on this: If currently a couple big muscle groups are carrying 100% of the workload on the bike, and we can train other perhaps smaller muscles to take 30% of that workload efficiently, doesn't that free up some more energy in the big muscles for down the road (perhaps higher biking speed or more endurance on the run)?

Also, I think that durability is one of the most important capabilities we can have, and if PC's lead to better running form, better utilization of muscles on the bike and run, and less running/biking injuries, their worth might lie there as much as in biking speed. With 25 years in the sport and heading into late-40's, durability ranks high in my book and I am always willing to try things to increase my chances of continuing the decades without injury. Hip Flexor strength has been strongly associated with durability and speed in all sports, so it seems that increasing the strength of this oft-overlooked muscle can't be a bad thing.

Though I do agree that for many triathletes, the money you have to shuck out for PC's might not be worth it compared to other items like a Power Meter. Taking the long-haul view though, it might be better to last longer in the sport than to crank out more watts for a couple of years and then blow up due to injuries. Food for thought...

As for me, the jury's still out, but I'm enjoying the challenge of riding on the cranks. My n=1 is that it took a couple of weeks of adaptation, but I can now do all of the EN workouts on the cranks and I don't think I'm resting my quads/hams on the downstroke currently. Time Trial competition this weekend at the Tri store had me at 205 watts (after a full week's worth of VO2 intervals), whereas my more-rested NovOS Week 8 TT two weeks ago gave me an FTP of 201 and start of OS was 182. So I think that overall the muscular adaptation on the bike is still proceeding, and I'm not just slacking off on the big muscles to spare the littles.

 

Kevin Walter

I tried Power Cranks for about 18-months 6-years ago. I managed to work up to riding them outside for up to a couple hours. My net experience was negative. I may have noticed some run gains, but my cycling suffered. The difficulty riding them resulted in less riding, less enjoyable riding, and lowered fitness for me. I basically gave my pair away.

Coach Rich

Kevin, Robin:

My net/net is:

• Did a tool (PC's) result in more watts to the rear wheel or faster mph (aero improvements)?
• Could I have achieved similar or greater gains with another, less expensive method in a similar time frame?

Last I check, and I can't say I've really checked, I've never seen a Before/After PC's watts comparison, though of course the same can be said of a lot of other things of course.

Jump4Joy19

@Kevin, I can definitely see how that would occur. I'm not sure when I'll take the cranks off, and I don't know yet whether I'll try riding them outside. From my house,  I have either a big hill to climb or a lot of stops between me and any roads that would be easy to ride on the cranks, so I'll have to see if I think it would be worth it. For now, I'm treating it as in indoors, wintertime project.

 

@CoachR, yes I definitely see what you're saying from an ROI perspective, especially 'cuz these things ain't cheap! Craig Howie does have some data up from the Boulder Center for Sports Medicine, tracking his experience: http://www.howieenduranceproject.com/Triathlon-Tips/power-cranks-review.htm, but there's not a lot of data out there. I would think it would be in the interest of the Power Crank people to do some before/after studies, pretty easy to do with Power data available for many triathletes.

My personal data will be useless since I threw the cranks on after a non-season (due to broken bone) and thus I started on them with less than my usual level of fitness. There's no way to say whether any gains made would occur the same without the cranks, just due to training again.

That being said, more watts to the rear wheel is not my only goal, so the ROI for me would be higher than it might be for others since I put a big premium on durability and strength, not just triathlon speed.

Also, for others who might be interested but find the price tag too steep, I found this: How to make your own power cranks for less than $6. I'm considering getting a welding friend of mine to make some up, and buying a clunker bike to throw them on so I can have a trainer-only bike with the cranks. It's just too unwieldy to keep taking them on and off a bike, and I don't have the luxury of having multiple bikes available to tie one up with the cranks right now.