Recumbent - Developing 'bent legs

It is often stated in the blogs that it will take some time to build up your ‘bent legs—even if your legs are already in shape from riding a DF bike. They claim that the muscles are used differently. Do you think that is necessarily true?

I think a lot of the problem has to do with the way ‘bents vs. DFs are fit to the rider. I am used to setting the height of my DF seat by putting my heel on the peddle and locking my knee so that my leg is completely straight. If I can spin the cranks like that without tipping my hips, it fits. When riding normally with my toes on the peddles, my knees keep a slight bend, and the muscles work in the range that gives maximum power.

In contrast, when I was shopping for a ‘bent, the sales people sometimes didn’t bother adjusting the length of the bike. If the bike was too long for me, they HAD to do something, but if it was too short, some sales people didn’t bother with it. Once I complained that it was too short, and I was told that ‘bent riders usually keep more bend in their knees. Sure enough, I looked though the photos posted on this blog and found that the majority of the riders do indeed have more bend in their knees than I would expect. Changing the angles of the knees would definitely take some training to get the muscles used to it. (Try lowering the seat on your road bike and see what happens to your power.) I am wondering if this is why people say it takes time to develop your ‘bent legs?

Is there a good reason for having a different knee angle on a ‘bent bike? I figured the salespeople just get tired of fitting the bikes properly because (on most SWB ‘bents) it requires lengthening or shortening the chain. It is a lot more work than fitting a DF correctly. To be fair, most of the salespeople I met were motivated and helpful. Maybe the difference in knee positions is due to the fact that most beginners (like me) don’t feel comfortable stretching out on their back when they are just getting started. They prefer the seat to be set straighter up and closer to the cranks. When they get used to riding, they might adjust the angle of the seat but not bother with the more complex task of increasing the distance between the seat and the cranks. After all, riding a poorly fitting ‘bent (once you are used to it) is still faster than riding a properly fitted road bike. So the problem can’t be that bad, right? However, if you want to go fast compared to another ‘bent, it probably helps to get the fit right. I noticed that the photos of high performance ‘bent racers looked more like what I would expect; those riders tend to have less bend in their knees than the typical ‘bent riders. So I am wondering if the transition could be made easier by adjusting the length of the ‘bent instead of the muscles in your legs.

The angle between the torso and the thighs might also take some getting used to. If muscle groups are used in a different range of motion, then it would take some training to build up strength in the new range. That being said, if the ‘bent seat has you lying flat, then the angle between the torso and thighs would be similar to sitting straight up on a DF bike. If the ‘bent seat has you sitting nearly upright, then the angle between the torso and thigh would be more like riding a DF with triathlon (aero) bars or bent in a low tuck on a road bike. I don’t think the angles in ‘bents and DFs are necessarily that different. The irony is that the angle that is used for racing on ‘bents is used for comfortable, casual riding on a DF, and vice versa. That means that riders at either extreme (racers versus casual/comfortable riders) would notice the biggest difference. However, the folks in the middle might use similar angles on both types of bikes. If the angles don’t change, then there shouldn’t be an adjustment period, right?

Please excuse my ignorance. I am new to ‘bents. I suspect these questions are a bit like a virgin asking what an orgasm is like--no amount of explanation covers it, but once you experience it you know. :rolleyes:
Unfortunately, I won’t be a good guinea pig for this new experiment (the transition to ‘bents), because I haven’t been able to seriously ride my road bike for years. Arthritis. On the bright side, if it wasn’t for that pain, I wouldn’t have gotten interested in the ergonomics of ‘bents and I would miss all the fun of this blog. ;)
Anyway, I won’t go through the transition like the people who switch while they are already in shape on DF bikes. I have to start from zero. So I know I will start slow no matter how the bike is set up. Still, I am very curious to hear from those who have felt the transition. What muscle groups hurt or felt different while you were developing your ‘bent legs? Can you link that to any particular changes in your body position? I would appreciate any light you can shed on this for me. Thanks.

The way you do it is the way I started out on my bent. After that there's just minor tweaking for the best position. There's no using body weight on a bent, so everything is up to spinning with your legs.

The angle between the torso and the thighs might also take some getting used to.
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I don’t think the angles in ‘bents and DFs are necessarily that different.

I think they are depending on the bike. I didn't feel like I lost a lot of speed on the P-38 because the angles were basically the same as the Cannondale I sold to get it--just rotated thirty degrees or so. But it's a different story on the EZ-1. I believe the more open angle reduces my ability to apply power. I can't back that up scientifically--it's just my perception.

I'd say your method is a good way to get 'in the ball park.' And that's all the better it did for me when I was riding uprights. After that point, there's still a good bit of personal preference to adjust around. I like my pedals just far enough out that I can 'unweight' my feet at the far pedal stroke without hyperextending my achilles tendon. Too far in and I'll get hot foot, too far out and I can't pull down on the far pedal to get it around the dead spot. (That wiping-the-feet motion you use to spin smoothly on an upright.) You can look at my pics from the 2005 Waterford HPV competition (http://s38.photobucket.com/albums/e135/blazingpedals/Waterford%202004/?start=0) to see some more experienced recumbent riders and how their extensions look.

RANS recommends (on their web site) moving the seat to a point where your leg is straight when your heel is on the pedal. Which gives a slight bend with the ball on the pedal. Just about like the traditional DF method. Yep, it gets you close.

Just checking in. I had a Strada w/RotorCranks 3 years back. I rode it for one season then sold it. No matter what kind of riding I did the possition drove my hip flexors crazy.

Chaz, lengthwise I'm set up just like I was on a DF. That is with my heel just missing the pedal with my leg completely straight. I know this sounds a little too long but for all my 30+ years of riding I've tended to "point" my toes a little so this setup results in the slight bend of the knee that you want at full extension while pedaling. I believe the "slight bend" setup is best for any bike. I really don't get the ones who say you want differently because it's a bent.

Soon after I started riding a bent I also gave a lot of thought to the body angles just like you described. I found pictures of bent and DF riders and rotated them so that the riders bodies lined up and presto, you're absolutely right the body positions aren't very different, simply rotated. That being said, there is a great deal of difference to the muscles your legs use between a DF and a bent. My first spring on my Corsa I was slow as a brick and had leg muscles hurting that I didn't know I had before. By the second year I was as fast as I had been on a DF and in the third year I was faster than I've ever been and now can even climb with most DF riders. So there is a big difference even if it has nothing to do with body position angles. Some say it has to do with the difference in gravity pulling your legs differently pointing down as on a DF vs. out as on a bent.

Caution, if you are sitting up enough that you can press the pedal while your back presses into the seat you can put as much power into the pedal as you would with a leg press machine.
I did this when climbing a steep hill in a high gear. Have a sore knee to prove. May require medical help.

Should have added.
Get your bent legs first. Then ride hard.

How will he know when he "has his 'bent legs" ?

It's said you have your 'bent legs' when you can ride your recumbent at more or less the same speeds you used to ride (your DF/previous bike.) Obviously the faster you were on a DF, the higher the bar has been set.

As far as needing to get 'bent legs,' I think any time you change positions, you're going to run into a bit of it. The more difference between positions, the longer it'll take. Even going from my Baron to my Nocom required a couple of weeks of adjustment. It was pretty strange that I couldn't keep up with my normal group when riding the Nocom, but that's just what happened. Now I can drop them even on a climb.

4/10/09 - edited for clarity

I am about to switch from a Hi-Racer (Bacchetta Corsa) to a new lowracer (Raptobike (http://duncan-brain.blogspot.com/2009/04/raptobike-coming-together.html)). I expect a few weeks of adjustment, I will not be able to push as hard with my training buddies. But it will all come together for the STP in July, so it will be fine.

I have my bent set up the same as when I road a DF. I did, however, have to add extenders to the pedals to move them out from the crank. I've read a lot of pro and cons for the extenders, but for me they cut out the knee pain I was developing - and I'd never had the knee pain on the DF.

I have been wondering about spinning vs. pumping. On a road bike, the force you can put into the pedals basically limited by your bodyweight plus whatever you can add by pulling on the handlebars. But as CHAS noted, a recumbent lets you push against the backrest so the force can far exceed your own bodyweight. Assuming that you build up to it safely, would a focus on pumping generate more speed than a (more balanced) spinning style with higher cadence?

I must admit that I never really got the hang of spinning (with high rpms) on a road bike. I want to try the tip from Blazing Pedals about unweighting you foot at the furthest point of the stroke. Any pushing force at that point is wasted anyway. I think that the unweighting would help me transition more quickly and naturally into the foot-wipe part of the spinning motion.

I suspect that even if the angles in the body are the same, the direction of gravity will make spinning feel more natural on a recumbent bike than on a road bike. The foot-wipe phase is gravity assisted, and the pull phase doesn’t have to fight gravity as it does on a road bike. I always hated the feeling of lifting my own thighs--especially if muscle mass is only a small portion of the total weight. :innocent:

CHAS noted that pushing with too much force can cause knee problems. (yup. been there. done that.) I read on another thread that focusing only on pushing can also cause knee problems even when you carefully build up the muscles because it can create a muscle imbalance. The doc told one guy to get clipless pedals and work on spinning to develop the other muscle groups around the knee.

I will also keep charly17201’s tip on pedal extenders in mind. I often road on the outside edge of my DF pedals to reduce knee pain. I haven’t noticed the need to do that while test riding recumbents, but time will tell.

So now I believe in the concept of ‘bent legs, and I have my training goals planned out. All I need now is my bike. :o Only one more week for delivery...I hope.

On a road bike, the force you can put into the pedals basically limited by your bodyweight plus whatever you can add by pulling on the handlebars. But as CHAS noted, a recumbent lets you push against the backrest so the force can far exceed your own bodyweight. Assuming that you build up to it safely, would a focus on pumping generate more speed than a (more balanced) spinning style with higher cadence?

The problem with the 'pushing against the seatback' logic is that it's wrong. When the going gets tough, upright riders stand. This allows them to pull down on the handlebars, meaning they can effectively put more force on the pedals than what they weigh. And they don't have their hips fixed in one place, which reduces the stress on their knees while they're doing it. Recumbent riders, on the other hand, *may* be able to push their body weight a few times. Remember, we're only pushing with one leg at a time, and it's a rare recumbent rider that can leg press double his body weight using both legs. Even if you're one of the few who can, it would be too tiring to maintain for long, AND you'd be doing it with the same muscles you used before getting to the hill as well as the same ones you'd have to use after finishing the climb.

I still see spinning as a balancing act between muscle strength and aerobics. At your max output, if your legs are burning, you need to drop a gear and spin faster. If you're at your MHR, then you should go up a gear and drop the cadence. If you're maxxed out AND your legs are burning, you've got it just about right. If you're training, you need days of both aerobic workouts and days of strength training. And of course if you're taking it easy, you can do whatever feels comfortable.

You make some good points. The ability to change positions is a real advantage of DF bikes. Working the muscles in a different range of motion or even shifting to different muscle groups really helps with prolonged output. The one drawback of that freedom of motion is that one often sees the frames swinging wildly from side to side. Moving the (ultra light) frame from side to side would only waste a tiny bit of energy. I suspect that more is wasted by stepping sideways on the cranks and frame. The energy goes into bending the frame rather than moving the chain. Still, I suspect that the benefits of being able to change positions outweigh the loss of efficiency due to lateral movements.

That got me thinking about the next generation of recumbents. I would love to have the option to adjust the seat position while riding. Some bikes do come with quick release bolts so the seat can be quickly adjusted, but you have to stop and get off. I would like to have a lever under the seat or knobs on the side like those on a car seat. You could also think about the flippers under an office chair. I would love to be able to shift positions when going up versus down hills, or lie down flatter when I turn into a headwind, or just move around in general if I get cramped up in any one position. That might be the best of both worlds: the ability to change positions without the problem of swinging side to side and getting out of position laterally.

I agree the ability to change positions is huge. Because even though I am very comfortable in my easy chair or bed, after awhile I still need to change my body position for comfort. A recumbent does not allow for this changing which, and after awhile, makes it uncomfortable for me.