Formula for how hard a ride is?

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Ming the Merciless

There is no mercy
Location
Inside my skull
The scale question is obviously relevant. I didn't plot that Season of Mists profile to make it look gnarlier than it is - I always adjust the vertical scale in my mapping software to show the 50 metre intervals as small as they will go. Any more compressed and the scale changes to 100 metre intervals.

Here is a comparison with the Manchester 100 profile with vertical and horizontal scales adjusted to match...

View attachment 702694

Season of Mists has around 2,500 m of ascent in just over 100 km; Manchester 100 has around 1,000 m of ascent in around 100 miles/160-ish km. My best time in both events was around 6 hours using about the same amount of effort, but the steep hills on SoM killed my legs more.

SoM is extremely hilly, with many climbs at 10%, 15%, 20%, and even a stretch of 25%; M100 is flattish-to-undulating with very few ramps as steep as 10%.

Still it’s only averaging 5% uphill overall. None of what has been talked about on this thread is hard, unless you are really pushing the intensity levels.
 

Dogtrousers

Kilometre nibbler
Still it’s only averaging 5% uphill overall. None of what has been talked about on this thread is hard, unless you are really pushing the intensity levels.
That's entirely subjective.

I'd consider a route like Season of Mists hard, or very hard. You might consider it less than hard. Neither of us is wrong. That's the nature of things. Language is ambiguous and people have different ability levels and perceptions.

It was to address problems of subjectivity that the OP started this thread.

Personally I think the idea of a single, easily calculated figure that gives consistent results is a folorn hope.
 
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Legs

usually riding on Zwift...
Location
Staffordshire
Still it’s only averaging 5% uphill overall. None of what has been talked about on this thread is hard, unless you are really pushing the intensity levels.

While I agree that the difficulty of a ride depends largely on how hard you push, there is a limit to how gently it is possible to push on very steep gradients; there are practical limits to how much you can gear down, and on very steep gradients, it is difficult to go very slowly (even if geared sufficiently low) without significant effort to maintain balance and traction.

Plugging my inputs into kreuzotter.de gives a speed of just 4.4mph for 250W on 15% gradients, which are not uncommon on British roads (particularly if you're looking for a challenging route). Even on a compact chainset (50/34), with a 32T big sprocket, this speed would still entail cadence as low as 55rpm (for many road bikes, this is about as low as it's possible to gear without serious modifications such as mullet gears). I can ride at 250W (3.5W/kg) for a few minutes without dying, but it's certainly not 'not hard'.
 
OP
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Deleted member 121159

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While I agree that the difficulty of a ride depends largely on how hard you push, there is a limit to how gently it is possible to push on very steep gradients; there are practical limits to how much you can gear down, and on very steep gradients, it is difficult to go very slowly (even if geared sufficiently low) without significant effort to maintain balance and traction.

Plugging my inputs into kreuzotter.de gives a speed of just 4.4mph for 250W on 15% gradients, which are not uncommon on British roads (particularly if you're looking for a challenging route). Even on a compact chainset (50/34), with a 32T big sprocket, this speed would still entail cadence as low as 55rpm (for many road bikes, this is about as low as it's possible to gear without serious modifications such as mullet gears). I can ride at 250W (3.5W/kg) for a few minutes without dying, but it's certainly not 'not hard'.

This is why I use MTB gearing on my mainly road going bike. 36/26 front 11-40 back. I reckon most people don't need anything harder than this. Most 11 speed road drivetrains are practically 9 speed because no one uses 50-11, 50-13 and 34-11, 34-13.
 

Legs

usually riding on Zwift...
Location
Staffordshire
This is why I use MTB gearing on my mainly road going bike. 36/26 front 11-40 back. I reckon most people don't need anything harder than this. Most 11 speed road drivetrains are practically 9 speed because no one uses 50-11, 50-13 and 34-11, 34-13.
Personally, I prefer to feel like the hills are a challenge, and to have to push myself that little bit harder to get up them. However, if I were touring I would definitely want lower gearing than my present 39x27 bottom gear, because honking with panniers is not fun!

36x11 seems a bit too small for me for those lovely (but rare) moments when you're bowling along on a gradual downhill with a tailwind at 35mph.
 

Alex321

Guru
Location
South Wales
This is why I use MTB gearing on my mainly road going bike. 36/26 front 11-40 back. I reckon most people don't need anything harder than this. Most 11 speed road drivetrains are practically 9 speed because no one uses 50-11, 50-13 and 34-11, 34-13.

I think most of us DO use the 50-11 and 50-12 ratios, just not on the flat. I certainly use them on shallow downhills (steeper ones you quickly go faster than even those can be used for).

34-11 or 34-12, Ok, those don't often get used (not deliberately anyhow) because there is enough overlap that most people will have changed to the big ring well before getting that high a gear in the small ring. I've done it a few times when I forgot I was in the small ring - hence the not deliberately.

36-11 would be way too low a top gear for most of us. That I could comfortably use on the flat, and would be looking for something higher. And I think the optimum range for a cassette should have you somewhere near the middle most of the time.

I have the fairly standard compact set up of 50/34 and 11-12-13-14-16-18-20-22-25-28-32. On the flat I spend most of my time in 50-14 or 50-16 (I try to keep my cadence in the 80-85 range most of the time), but I am very gad I have those higher gears available. I don't believe I am particularly unusual in any of those.
 
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Deleted member 121159

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I think most of us DO use the 50-11 and 50-12 ratios, just not on the flat. I certainly use them on shallow downhills (steeper ones you quickly go faster than even those can be used for).

34-11 or 34-12, Ok, those don't often get used (not deliberately anyhow) because there is enough overlap that most people will have changed to the big ring well before getting that high a gear in the small ring. I've done it a few times when I forgot I was in the small ring - hence the not deliberately.

36-11 would be way too low a top gear for most of us. That I could comfortably use on the flat, and would be looking for something higher. And I think the optimum range for a cassette should have you somewhere near the middle most of the time.

I have the fairly standard compact set up of 50/34 and 11-12-13-14-16-18-20-22-25-28-32. On the flat I spend most of my time in 50-14 or 50-16 (I try to keep my cadence in the 80-85 range most of the time), but I am very gad I have those higher gears available. I don't believe I am particularly unusual in any of those.

Ideally I'd like 40-24 as 40-11 is the biggest gear I personally would ever use. With 36-11 you do spin out on descents quite quickly. If anyone knows how to fit 40-24 cranks on a BB86 frame, let me know as my conclusion is it's not possible. But 50-11 gives you 33 mph at 90 rpm. I wouldn't pedal at all at that speed. When I say most cyclists I mean out of everyone who cycles, not necessarily everyone who is a trained cyclist. Most bikes are over geared for most people who cycle.
 

Alex321

Guru
Location
South Wales
Ideally I'd like 40-24 as 40-11 is the biggest gear I personally would ever use. With 36-11 you do spin out on descents quite quickly. If anyone knows how to fit 40-24 cranks on a BB86 frame, let me know as my conclusion is it's not possible. But 50-11 gives you 33 mph at 90 rpm. I wouldn't pedal at all at that speed. When I say most cyclists I mean out of everyone who cycles, not necessarily everyone who is a trained cyclist. Most bikes are over geared for most people who cycle.

I was still pedalling on tonight's commute at the peak speed I hit (32.7mph according to strava - I wasn't looking at my Wahoo much at that speed).
 
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Deleted member 121159

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I was still pedalling on tonight's commute at the peak speed I hit (32.7mph according to strava - I wasn't looking at my Wahoo much at that speed).

You can certainly pedal at that speed but in my view it's past the point of diminishing returns as just tucking into an aero position will likely give similar or better results. That's my experience anyway on descents. Of course perhaps you push those gears on flats at that speed and if that's the case kudos to you!
 
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Dolorous Edd

Senior Member
How about (if you have the data):

- Download all your rides from VeloViewer
- Plot average HR of all long rides of broadly similar duration against a measure of elevation 'intensity' (e.g. feet of ascent per mile)
- Draw a best fit line and express as a formula
 

Dogtrousers

Kilometre nibbler
How about (if you have the data):

- Download all your rides from VeloViewer
- Plot average HR of all long rides of broadly similar duration against a measure of elevation 'intensity' (e.g. feet of ascent per mile)
- Draw a best fit line and express as a formula

Unless you always ride at the same intensity level, it would run into the problem that the same route could be hard or easy, depending how you rode it.

But if you have enough rides there might be enough data to average it out.
 

presta

Guru
Unless you always ride at the same intensity level, it would run into the problem that the same route could be hard or easy, depending how you rode it.
But there's a difference between how hard the route is, and how hard a pace you set yourself.

At the time when I was still cycling I used to calculate the regression coefficients for average speed as a function of average heart rate for local training rides, then compare my speed for each ride against the calculated speed for whatever my heart rate was for that ride. That way I could see the difference between getting fitter and just working harder.

It seems to me that a system for gauging the difficulty of a route that's simple enough to do, and of some practical use is to estimate the time it takes to cycle it using ascent and distance like walkers do with Naismith's rule. It's easy to calculate your own personal Naismith's rule if you download the Data Analysis pack into Excel, then just cut & paste your data in and it will do all the regression for you. Once you've calculated the coefficients retrospectively you can then use them to estimate the expected time for future rides.

I did this one with the data from a couple of my tours:
 

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