power and aerobars

bikeguy said:

Any other suggestions to prevent the hyperventilation while in aero position - I'm thinking a stem length change and aiming my aerobars more upward than usual will help.

-bikeguy

Yeah any way to increase the distance between top of the leg and stomack, euh well diaphragm (below the lungs).

The angle may be too tight at the moment. You may be loosing biomechanical efficiency as well by being too compact.

have a look here, there are some good articles and pix:
http://www.trysport.com.au/services.htm

gclark8 said:

have a look here, there are some good articles and pix:
http://www.trysport.com.au/services.htm

Uhh.. like where? I do TT's and cycling only not tri's. Sometimes I do look at slowtwitch as there is something interesting in the forums sometimes.

-bikeguy

bikeguy said:

Uhh.. like where? I do TT's and cycling only not tri's. Sometimes I do look at slowtwitch as there is something interesting in the forums sometimes.

-bikeguy

This one isn't bad neither... http://www.timetriallingforum.co.uk/

As for triathlon, my favorite site (by very far), would be http://www.tritalk.co.uk/forums

Right now this board is down as a result of a hacking attack. But they're going to be back. Bob Tobin (among others) is a (sporadic) contributor. Hywel Davies (Hdavies), Adam Young (Younggun), Stuart Ashley, Paul Newsome (Swimsmooth), Phil Skiba (Philibert)... all these guys know a thing or two about time trialling.

Thanks SolarEnergy for the link to that TT site, I am checking it out.

-bikeguy

I found that I reduced my HR and discomfort by widening the arm-rests (10 inches between centres). This maybe less aerodynamically efficient, but it means I can stay in position for long periods. I assume you're using a frame with a steep seat tube angle if you're doing TT's, as this was also something that I found was helpful for comfort in position.

bikeguy said:

I have an annoying problem during time trials - my power on the aerobars drops so much that I can ride as fast (98%) sitting almost bolt upright as on aerobars. Any kind of grade, and being on the aerobars will send me into the land of hyperventilation, as well as slowing me down for the rest of the TT (I go to the tops on any hill over 3% and 100 meters long). This problem is so bad that any excessive use of aerobars up a hill will substantially negatively impact my TT. It happens real fast - 20 seconds and I'm already in trouble.

I've trained somewhat on the aerobars in TT position but the problem is not really improving - I generate enough power to go 45 kph on the flats but I can't do it because I can only generate that power riding upright (means I'm a good climber though). Turning over slower helps - and I've got a 52x11 setup ready for spring.

Any other suggestions to prevent the hyperventilation while in aero position - I'm thinking a stem length change and aiming my aerobars more upward than usual will help.

-bikeguy

Pics? Sounds like you may be too cramped (at the hip) in your aero position, i.e either too low in front or too far back or both.

I assume you're training hard in the aero position at least once a week (in-season)?

After 2+ yrs of mucking about, for a given fore-aft position I found there was just so low I could go in front and still output close to road bike power (sustained power 5-20min). Below that I had a dramatic drop-off close to 10% for 1cm under. In addition if I hit a grade as you describe only 3-4% and wanted to get into L5 power range, it felt absolutely terrible when too low.

But I couldn't tell any of this without experimenting and using the PM for all my hard training runs and TT's. Now I'm just (re) focussed on getting the power up.

I had these pics taken, I realise they don't quite represent my true position on the bike because my feet are on the ground, but the arm position should more or less be what I tried during the later TT's.
side & front

I think my arms are too far out in front, maybe I should shorten my stem too? This was the bike I rode during the TT's: here's a shot during a TT
where I was in the drops again because I started hyperventilating.. I think the guy behind me had started 2 minutes after me. I'm panting in this shot. My legs didn't feel tired - no burning, no heavyness, nothing.

during TT

bikeguy said:

I had these pics taken, I realise they don't quite represent my true position on the bike because my feet are on the ground, but the arm position should more or less be what I tried during the later TT's.
side & front

I think my arms are too far out in front, maybe I should shorten my stem too? This was the bike I rode during the TT's: here's a shot during a TT
where I was in the drops again because I started hyperventilating.. I think the guy behind me had started 2 minutes after me. I'm panting in this shot. My legs didn't feel tired - no burning, no heavyness, nothing.

during TT

I'm sure folks would like to help but I can't tell very much from those static shots not clipped in. I'd try some static shots from the side while riding a trainer and make sure you get the top and bottom of the pedal stroke. Sit as you normally do and in the aero position. Ideally take the shots while putting out close to TT power on the trainer. Sometimes 'posed' shots are just that.

In the static shots the bars are angle severely downwards while in the TT shot they are up. Which one are you using now?

Re hyper-ventilating while undergoing no sensation of leg pain/fatigue - only thing I can ask is: are you spinning 120+ rpm? :eek:

Personally I spent quite a lot of time searching the net for pics of the best TT'rs under power. Guys like Cancellara, Zabriskie, Millar, Wiggins come to mind. You could do worse than simply emulating them.

rmur17 said:

Pics? Sounds like you may be too cramped (at the hip) in your aero position, i.e either too low in front or too far back or both.

Some pics in the post above, unfortunately not one from the side while in real "TT mode".

rmur17 said:

I assume you're training hard in the aero position at least once a week (in-season)?

Yes, I did twice per week but only 15-20 km. All the TT's I did were the first time I saw the course, so I could improve a bit just from familiarity with the courses.

rmur17 said:

After 2+ yrs of mucking about, for a given fore-aft position I found there was just so low I could go in front and still output close to road bike power (sustained power 5-20min). Below that I had a dramatic drop-off close to 10% for 1cm under. In addition if I hit a grade as you describe only 3-4% and wanted to get into L5 power range, it felt absolutely terrible when too low.
But I couldn't tell any of this without experimenting and using the PM for all my hard training runs and TT's. Now I'm just (re) focussed on getting the power up.

In fact I'm considering getting the polar power system just so I can evaluate positions, power output and the time I can hold it, and speed since I already have a S725X and HRM monitor. Of course it's good for monitoring training and making sure you train hard enough too + pacing. I am getting it.. this problem irks me.

-bikeguy

rmur17 said:

I'm sure folks would like to help but I can't tell very much from those static shots not clipped in. I'd try some static shots from the side while riding a trainer and make sure you get the top and bottom of the pedal stroke. Sit as you normally do and in the aero position. Ideally take the shots while putting out close to TT power on the trainer. Sometimes 'posed' shots are just that.

I realise this and will get new photos up next spring.

rmur17 said:

In the static shots the bars are angle severely downwards while in the TT shot they are up. Which one are you using now?

My last TT was slightly down, not as much as in the standing photos.
More up seems to definitely be better.

rmur17 said:

Re hyper-ventilating while undergoing no sensation of leg pain/fatigue - only thing I can ask is: are you spinning 120+ rpm? :eek:

No, I prefer grinding at 80 rpm or even low 70's.. ventilation increases significantly over 95 rpm.. particularly if I'm on aerobars. :eek: I had 50x13 available as the highest gear during these TT's. I'm moving to a 52x11 on the TT bike. I have a problem with tailwinds, by necessity you have to go fast with them and that means RPM's start to go high.

Even at 80 rpm, I do not feel fatigue in my legs up normal grades or on the flat at say 400 W, like during my VO2 max test, I fail because of pain in the chest/thorax/rib cage and hyperventilation. Of course if the grade is like 8% plus then I'll start to feel fatigue in my legs at 75 rpm, but again it is hyperventilation and pain above my waist that stops me.

rmur17 said:

Personally I spent quite a lot of time searching the net for pics of the best TT'rs under power. Guys like Cancellara, Zabriskie, Millar, Wiggins come to mind. You could do worse than simply emulating them.

I'm going to go the power meter route and find definitive answers. I'll see how the TT frame feels.

-bikeguy