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Message started by reever on Oct 22^nd, 2014, 5:13pm

Title: Little trick to boost power
Post by reever on Oct 22^nd, 2014, 5:13pm

I don't know if anyone else has come across this little trick to boost your power going up hill or into the wind, but I use it all the time. When I need a little help in keeping the RPM's up, I point my toes up and push my heel down. This does a few things.

First off, as those of us who have bit off a little more than we should on the bench press have noticed, while we might be able to handle the weight when our arms are almost straight, we rapidly lose that ability as our arms bend. We are strongest when we are closest to full extension. And just fractions of degrees help loads. When you point your toes up you increase the knee's angle to closer to 180 degrees, or straight.

Secondly, it brings in a few other muscle groups that aren't used that heavily during normal riding--namely the muscles on the front of the shin and some flexors up in the hip.

Try it out and see if it helps you on your next ride........

Title: Re: Little trick to boost power
Post by LordMarv on Oct 26^th, 2014, 5:51pm

Hey Reever! I assume you are clipped in? I am not clipped myself, but I did just go out for a ride and I'll be darned, just that minor change does help! Being unclipped myself, I had found that shifting from pedaling with the ball of my foot to the mid-sole can also give me a little boost for awhile. Amazing what a minor shift or tilt of the foot can do. [smiley=cool.gif]

Title: Re: Little trick to boost power
Post by gfreeman on Oct 27^th, 2014, 10:16am

Reever, I am curious about the degree of leg extension that is most efficient. One of the guys at RBM adjusted my seat forward, so that I am not fully extending when I pedal. Many years ago, when I was an upright rider, everyone believed that seat height that gave full extension was the way to go. Apparently not anymore. Why would you not want full extension?

Title: Re: Little trick to boost power
Post by reever on Oct 27^th, 2014, 5:07pm

I do ride clipped in....if you are not clipped in you would not feel the extra force on the front of your shin or the hip flexors, but you would still get the power boost from getting your leg nearer to full extension at the knee.

When I got my first recumbent my local bike shop guy put it together and adjusted the boom for me. He was strictly an upright guy with no experience in recumbents. He grossly under-extended the boom for me. Once I did some reading on the subject I went back and had him extend the boom and (BOOM!) I had an immediate increase in power. We in the laid back world need our legs to be closer to full extension because we cannot vary that angle as readily as uprights can by moving around on their seats or standing up on them. It also explains why so many recumbent riders go with a shorter pedal arm length so that they can engage each pedal stroke nearer full extension.

Glad you tried the little trick......every little bit helps, huh?

Title: Re: Little trick to boost power
Post by rmillay on Oct 27^th, 2014, 7:26pm

On a DF full extension gives you a boost in power, and is favored by many triathletes. But it also stresses the muscles more, and results in the pelvis rocking side to side, which can be distressing to the seated parts. That's OK for a time-trialer, but will kill any passion for long distance riding. If you race, you go for any advantage to pick up speed, but riding for pleasure suggests a more moderate adjustment. Hence, reever's suggestion may be helpful for some, as you don't have to be adjusted to the extreme to take advantage of it.

Title: Re: Little trick to boost power
Post by FlyingLaZBoy on Oct 28^th, 2014, 4:01pm

On the Xstream, I find that "straight" leg extension results in LOSS of climbing power... this is partially due to the distance to the pedals changing slightly when you are cranking it, because of the seat foam compressing more than normal. So I probably have my seat a bit further forward than optimum for "regular" riding, so as to not lose power when pushing hard.

Title: Re: Little trick to boost power
Post by reever on Oct 28^th, 2014, 5:05pm

You know what got me thinking about this was watching videos of these guys over in the Netherlands riding their recumbents. They are so near extension and have such short pedal cranks that it looks like they are just getting around by flicking their ankles--just a slight bend of the knee and a flick of the ankle. They've been at it a little longer than I have, so tried to imitate their set up. I'm not quite there, but by getting a little closer to extension I did pick up power.
I can't get all the way to full extension due to a knee with some partially torn ligaments in it. If I get to full extension the knee wants to just keep right on going past that point. Not fun!

Title: Re: Little trick to boost power
Post by Monkeywrangler22 on Oct 29^th, 2014, 7:55am

But, IIRC, the Netherlands is not known for having much in the way of hills. Really short cranks may work for the flats, but would make hills harder.

Title: Re: Little trick to boost power
Post by reever on Oct 29^th, 2014, 8:43am

Yes, everything is a tradeoff, and it comes down to how much muscle you have in the end. But technique can help us get all we can from the muscle we've got. The neat thing about recumbents is we don't have to worry about pivoting around that upright seat with our hips if we have things adjusted 1/4 inch too long. It's painful to remember the old days!!!

The shorter cranks will help you save your knees, as well, allowing you to begin your "push" at an angle at the knee joint that is closer to extension. Good point on the hills, Monkeywrangler......

Title: Re: Little trick to boost power
Post by jayg on Oct 29^th, 2014, 12:47pm

165 mm, and longer, cranks give my knees fits. Been using 150 mm cranks and extending my recumbents' booms so the angles of my knees are greater than 90 degrees at the beginning of the power strokes. Results in my legs being pretty well extended at the bottoms of the strokes. My knees and performance have much improved. I can maintain decent speeds on short hills by staying in the middle ring, downshifting and putting some power to the pedals. On steep, long hills, like encountered at the Lancaster and Muenster pay rides, I drop to the granny ring and spin. Haven't walked a hill since I've been riding with short cranks. Installed smaller rings on the cranksets (48T/38T/24T). Use 10-speed, 11T/32T cassettes on bikes I ride at Lancaster and Muenster. For all other riding I use 12T/27T, close-ratio cassettes.

Title: Re: Little trick to boost power
Post by rowenusmc on Nov 5^th, 2014, 7:10pm

I started riding 155mm cranks while still doing triathlons on DF bikes to save my legs for the run. Still use the short cranks on my recumbents even though I live in a hilly area. I usually just set my seat at less of an angle for climbing.