Uphill v downhill power

For indoor workouts, would you say that you find it easier on the trainer to ride threshold by purposefully holding those watts or instead by using ERG?

Did 2 years spin classes on a Stages SC3 indoor spin bike at the gym. About a year later got a Kickr 2017, used Erg for 2 years. Then last two years I switched to mostly outside, and inside Kickr in slope/standard/level mode.

Indoors I find everything easier in resistance (SC3) or slope/standard/level mode (Kickr).

Gym rides before getting the Kickr, have a few structured rides in the gym including these 40/20s comparing gym to Kickr Erg/PowerMatch (Taylor),

and this Sept 2017 gym ride

of ~1.75 hours on the Stages gym bike and it starts with 5-min vo2 intervals before the class started, with the last 50 minutes being a spin class. Zwift running/recording on my iPhone, and those are in pure resistance mode (no erg on that gym bike). A couple months later I bought the Kickr v3 direct-drive and was scratching my head about why everyone was saying Erg was a game changer.

Uh…I just said:

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You need resistance to produce power. Once you get sufficient momentum going downhill there isn’t enough resistance to sustain a high power output, you either run out of gears or spin out or both. Anything steeper than a couple of percent downhill and I reach that point in maybe 30 seconds.

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how do you run out of gears at 36mph? Even with 50t you should be able to pedal closer to 45mph.

If you’re running out of resistance at less than 40, your big gear must be tiny. My hunch is that you’re not in your biggest gear and you’ve convinced yourself there’s no reason to try. If you haven’t taken the time to experiment, I’d recommend it. Either find a long downhill or motorpace *(at your own risk). In the low to mid 30s, you won’t even need your biggest gear.

Anyway, I never argued that everyone can make good/more power going downhill. I just said I can.

Same! I suspect there’s a benefit to training this way also. Otherwise, nobody would motorpace. One obvious benefit… When you can do the same watts at a lower RPE, you’ll be able to do it longer and enjoy your training more.

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Did you actually read my post? Firstly, what the heck size of gear do you need to pedal at 45mph with a 50t chainring? :rofl:

I don’t run out of gears at 36mph, I run out of gears in a couple of hundred metres at 300W on a -4% gradient at a speed well over 36mph. I’ll state again, 300W downhill you will continue to accelerate until you can’t pedal any faster. Why don’t you find a hill that’s at least a mile long and try to pedal down it at 300W. Then come back and tell us how long it took you to run out of gears and what your maximum speed was.

Well done for makin more power going downhill. I wait to see how this translates into results.

Pointless thread.

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This (+ a lot)

@F10naGodless my biggest gear is 50x11, I spin out at about 120rpm which according to http://www.bikecalc.com/speed_at_cadence is around 68km/h. However I’m not going to be putting 300W through the pedals at those figures when going downhill because the bike is effectively moving away from me and I’m actually trying to catch up.

Agree, although I could say the same about the podcast assertion that inspired this thread.

My results are pretty simple - not having to pause outside workouts in rolling terrain. Improved intensity control to not burn mini-matches.

Power to maintain 36mph on a -4% says a lot about headwind and aerodynamically if you are built like a truck or a race car. Sounds like I’m the guy putting out power on downhills to chase aero dudes like you :wink:

I had a little look back at my rides again…

9mph to 34.9mph. Total distance was 0.1 miles and needed 179W over 3 seconds on a hill with average about 8% decline The rest was coasting. Max power was 250W. That’s a mountain bike with XC tyres on tarmac :star_struck:

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A gradient of -4% for long enough you’ll hit 36 mph without trying. Certainly doesn’t take 300W to hit that speed downhill.

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Did some quick Strava science, using Veloviewer to search my segments, and pulled up a popular route that undulates a bit and averages -3.1%

Not perfect. Whatever, its quick & dirty Strava science.

Strava leaderboard:

https://www.strava.com/segments/17636601

KOM is local pro cyclist Cole Davis, he drilled “Erg mode” for 4 minutes at 311W average:

Zooming out, looks like a 2x28-min at ~300W with a 6 minute recovery interval:

That’s what I’m talking about, outside Erg mode!

Number 2 on the leaderboard let off the gas on the steeper sections of the descent:

Remove the coasting and he was averaging about 280W.

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Here’s my Strava from yesterday. Max downhill gradient of ride was 5%, but looking at Strava speed graph my max speed was on a longer 2.1% average hill , hitting 57.3km/h , which is 35.6 mph. My ftp has never been 300 watts in the time I’ve been able to measure power) and is probably closer to 230 watts at the moment, as I finish my base.

There is a limit to how steep the hill can be. And I’m positive I have qualified my statements in previous posts as “up to a certain gradient.” eg, I am aware that sometimes a hill is so steep that you outrun your gears.

I also mentioned that it’s hard to maintain high power after cresting a difficult uphill section.

And it’s hard to keep the power up on rolling hills bc it takes a while to get into the right gear and often we are on roads that just go up and down so quickly that you’re already going back up before you could settle into a fast high-powered downhill.

With all of those disclaimers repeated and out of the way… you appear to be saying “There’s this one hill I ride where it can’t be done so it can’t be done by anyone on any downhill.”

I will respond to your data with this: There are millions upon millions of downhills where you can pedal as hard as you want and not exceed 68kph. There is nothing intrinsically happening on a downhill that prevents you from hitting good power as long as you have the gears for that particular gradient.

So I go back to my original claim: I, unlike Jonathon, have experienced hitting better power for any given duration going downhill than going up.

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Why don’t you post evidence of this phenomena? I’ve seen no link to a ride demonstrating this…

@F10naGodless muscle motor pattern recruitment is very different climbing than while riding flats or descents. Descending your firing muscles over a much shorter arc to of the pedal stroke “top off” the energy compared to climbing. Even if cadence is the same, climbing your kinetic energy is lower, your traveling slower, working against gravity and therefore your need to exert torque on the pedal over a much longer arc to sustain your power.

FWIW I’m a bit like you. Also, I didn’t read the thread. If this was discussed disregard. Lastly, I sure miss all the roads to the west of Boulder. Just flew over it the other day and told my wife we’re moving back! Cheers