Riding into a headwind

But why should the resistance get “exponentially harder” during the pedal stroke? As a function of what?

:arrow_up: This.

I too struggle more to keep the exact same power in a headwind or uphill vs in a tailwind, downhill or in a fast travelling pack. Part is psychological, but most is power application. Inertia is key as far as I can tell, as when you travel fast the bike acts as a pseudo-flywheel of sorts (increased inertia of the whole system). This allows you get away with adding power in a much narrower arc of your pedalstroke. At least that’s what the mechanical engineer in me believes…

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Didn’t start off like that, just the opposite I was able to do long climbs at endurance pace (70-75% FTP) but I’d get popped in 20 minutes on the Wed night headwind hammerfest.

It literally took an entire year (all of 2016) to take it from 20 minutes to an hour and it was mostly mental.

Most training programs use 20 minutes as the longest sweet spot interval. I think that contributes to the mental roadblock.

Aerodynamic drag increases with the square of speed.

And power required to offset aerodynamic drag increases with the cube of speed.

Riding at 20mph takes 8 times as much power to overcome aero drag vs riding at 10mph.

During the pedal stroke, the bike accelerates forward - so increases in speed. Due to the increase in speed, the aero resistance is increasing exponentially.

This is nerdy math stuff. But enough people notice a different feel between riding hills, fast TT, tailwind, headwind, etc. where this effect must be noticeable.

Hmm nothing special about holding endurance pace for a long while :woman_shrugging: .

But yeah, appreciate the fact that you had to work for your “love” of headwinds. I will try to change my mental attitude and embrace the challenge. It won’t magically improve my power, and I still think that there is something physical to the problem, but whatever it is, it will improve with practice :slight_smile: .

Yeah I know, I was just confused by “exponential” because it’s really just v^3.

I still have to think about this… I’m really assuming that we’re riding at “constant” speed, or “as constant as possible” (I know power and hence speed won’t be perfectly constant over the course of the pedal stroke)… whatever accelerations there are they should be minimal…

I literally laughed out loud while typing that :wink: Just being honest, back then I was simply learning as a sub 3W/kg newbie to survive for an event that would require climbing for 8 hours. And simultaneously learning to survive a brutal 40-60 minutes of headwind on Wed night worlds.

Really don’t know if I changed any pedaling mechanics, doesn’t seem like it. What did appear to make an impact was spending a year pushing my time at FTP out to 1+ hours. Also from a recent thread the data shows I was able to routinely do 2 hours at ~88-90% FTP. And I was doing a fair bit of long 3+ hour tempo rides with the climbing rides being done at lower cadence (often ~60rpm) due to my low W/kg and gearing.

Once I reached that level of fatigue resistance it seemed like everything became easier. Some of that was mental, and some was physical the primary being strength/muscular endurance. Perhaps some other physiological changes were going on. It sure didn’t feel like anything related to pedaling mechanics.

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Sustained 300W at 60rpm compared to 90-100rpm sure feels like there is a huge difference in pedaling mechanics as it relates to making power.

I think riding up or into the wind engages more muscles, increases CV strain and depending on how a rider pedals and makes power can be night and day.

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My muscles get tired sooner when pedaling at 60rpm (at 220-260W based on my FTP), however I don’t perceive any material change to my pedaling mechanics :man_shrugging:t2:

And my point still stands, when I ride into the wind in a ‘climbing position’ (hands on hoods) then there is almost no difference. If I get into a more aggressive aero position on an endurance bike (LOL that is an oxymoron) then my HR will climb. What helps me achieve higher power in aero position is to tilt the nose of my SMP Selle Drakkon down 5%:

Fit report from 2016, I subsequently pointed the saddle down further and found that I could put out the same power in my aggressive aero position. And by doing that my HR is more stable and doesn’t rise as much.

The other thing I’ve noticed based on dialog with my coach - I’m actively engaging my glutes on both the flats and on climbs. That was either naturally or picked up during my first year of riding into headwinds.

Yes, they’re small, but must be big enough for people to notice based on how many people comment.

It’s similar to comments about high vs low inertia riding, big ring vs small ring, uphill vs TT, etc…

Just did my nth million flat hotdog loop with tail/headwind of about 15mph. Whatever is going on to stay on top of the gear same power and close the the same cadence my hr was slightly elevated into the wind. I held the same “breakaway” position with the wind and into it. I felt like to make power I was ankling a bit more. With the wind was just so easy to tap out threshold power. I will admit I was concentrating more into the wind to make power or at least just stay on top of the gear as it was a touch gusty…perhaps the gusts are key? With the wind they are muted and power is stoic. Into the wind they are amplified and therefore power trends more variable. IDK. Interesting.

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Yes, the elevated HR was what I noticed most too. I think you’re right in that you engage more muscles into the wind (maybe to hold the bike steady, especially with gusts?), and that creates a higher CV demand. Which in turn makes it feel harder than with the wind.

I nearly did a similar test today, but the wind was a bit too much of a cross wind. It’s bearly always windy here though, so will get abother chanve soon…

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Man cadence was really even but, it was slightly less into the wind. I just feel the way I pedal into the wind is different. It’s possible I’m doing exactly the same things. It just feels more “mashy” when you shift into an easier gear to stay on top even though over the average cadence is the same. Conversely, shifting into a harder gear to keep pressure on the pedals with a tail just feels way different from a physiological standpoint.

I don’t really care…just interesting.

I’m really glad you observed the same thing as me though, HR goes up, and it feels physically harder. Maybe because the bike is slower, pedalling is more jerky?

Apart from finding it interesting, I’d also love to find out what those people that don’t find it hard do different - different pedalling style or weight balance? More vo2max, so less CV impact?

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  1. “Slow and jerky” at 48rpm / 4.2mph up a 10% climb almost 3 hours into a ride:

Low momentum and smooth power.

  1. Into a strong 12mph (gusting 20) headwind during a 20-min field test:

Smooth power at 88rpm / 20.4mph (high momentum).

Comparing 1 and 2, power looks just as smooth in both high and low momentum cases. Sure riding at low momentum feels different, but I’m modulating power delivery to make it just as smooth. HR roughly the same, although I was a little amped about the field test and HR was higher.

  1. A week ago on flat windless evening:

Smooth power at 81rpm / 21.3mph and well above threshold (my current ftp is closer to 260). Again similar smooth power graph like the 10% climb and strong headwind 20-min field test.

HR similar to the two above.

  1. Last night into a 5mph cross/head wind (about 45 degree angle) while riding 3rd wheel behind two smaller guys (60/65kg) in a straight paceline:

Jagged power, a lot of anaerobic efforts, 100rpm / 25mph and higher heart rate. First time riding in a paceline in one year, so I was a little amped holding a wheel at 25mph on a new bike and that also caused HR to increase.

Looking at other (group) rides when power isn’t smooth and spiking into anaerobic zone, that is when I see an increase in HR.

When riding solo I’m usually able to modulate power delivery into a headwind and keep it just as smooth as when climbing. When I’m NOT able to tightly control power and it gets spiky, then HR rises.

Not sure if that helps…

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I think this is the key to riding into headwinds - they are far less consistent than a climb meaning it’s a battle to keep a consistent effort with much greater variations in power required to do so at different points of the pedal stroke. Put it another way the wind might blow harder at any point during your pedal stroke whereas on a climb this more influenced by how you choose to pedal rather than dictated to you.

agreed and that was the reason for posting screenshots - its my belief that you can reduce power variations while riding into a headwind (at least when riding solo).

these two power graphs look the same:

  • #1 which is low momentum <5mph and <50rpm climb up 10+% grade
  • #2 which is high momentum 20mph and 88rpm into a strong 12mph headwind (gusting to 20)

Why? Scenario #2 is riding SOLO into a headwind. From experience if I lazily push the pedals over the top, then the nice consistent power disappears. So long ago I learned to push hard thru the entire downstroke on both the flats and climbs, and to make minor adjustments (modulate pressure/torque) in response to conditions.

In both cases its basically threshold power and threshold HR.

Scenario #4 is a lighter head/crosswind vs #2 and a group ride (not solo). About 50% power at vo2max/anaerobic levels and HR increases. The wind while drafting other riders is adding to the challenge, along with having to watch wheels, looking for road debris, etc. Maybe others have mastered more consistent power in this scenario, that is about as good as it gets for me.

re: scenario #4, luckily the two guys in front and one behind me had power meters. Here are Strava power graphs of riders 1-4 pacelining on a ~4 min / 1.5 mile Strava segment into 5mph cross/headwind on Wed night:

  1. 1st Wheel pulled the whole segment, he is a smaller and more aero rider pulling 223W average which is just below his FTP:

  1. 2nd Wheel another smaller more aero rider getting a nice draft (137W avg):

  1. 3rd Wheel (me) a bigger less aero rider getting no real draft and dealing with choppier air requiring 250W avg just below estimated FTP, and a lot of excursions well above FTP:

  1. 4th Wheel another bigger less aero rider about my size and getting a nice draft (141W avg) and his FTP is ~280-300 so easy spinning for him:

Notice how 1st wheel has smoother power graph. He is a masters 55+ rider and has some podiums on crits and road races. Really smooth and fast rider on the flats. Not sure if that proves anything, but aligns with my earlier claim. Also notice how power gets choppier as you go back into the paceline, and it gets harder in a cross/headwind to smooth out the power.

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I don’t think this is totally true. There isn’t a single road in the world with a perfectly consistent gradient. Sure, the climb might average 8%, but there could be times when you’re on a section that is greater or less than the average. This would impact pedal stroke and power.

Living in Minnesota which a very flat, but windblown state I encounter headwinds on every ride. I’ve learned how to ride them.

I chalk the higher RPE and cardiovascular demand mostly to psychology. It comes down to expectations vs reality. There is more compensation in headwinds to hold speed. “I know I can hold 20 mph here! Wind be damned! Wait, am I cracking? :worried:

In other words, I believe it’s 90% psychological and 10% physiological.

I agree but I would say that on climbs you can see and anticipate gradient changes, unlike with the wind where you simply react…