Retro Grouch 

Why not just throw away your bike computer?

You'll lose all of that weight and you generally estimate that you've gone much farther and faster. I'm heading out for a double century (estimated) right now.

NotAsFat

A 25-mile ride w/20 mph crosswinds all the way is a lot harder than the same ride on a calm day. Time spent riding is a reasonable measure, as long as you count your workout time separately from recovery rides and other "fluff" rides.

Yen

I don't know how long you've ridden, but that's not my point. My original post was tongue-in-cheek, just a joke, not to be taken this seriously. I won't go on to explain myself any further.

jppe

If that were allowed you would not have the incentive to continue to invest in bike upgrades like so many of us have..........so NO!!!

tsl

I'm not disputing that at all. There's a considerable difference in the amount of effort required to propel my Giant Cypress DX or to do the same with my Trek 1000.

But that doesn't change the length of a mile. Further, one hour spent in the saddle of each bike is still 3,600 seconds. The Giant--while easily 10 or 12 pounds heavier than my Trek--is simply not massive enough to warp spacetime to a significant degree.

A measurement that takes into account the difference in effort between the two bikes might be watt-hours or miles per watt-hour. Or something else entirely--I haven't given it enough thought.

BluesDawg

There is no need to look for formulas to equate one effort to another. Miles, elevation, time, temperature, number of riders passed, number of cars on the road or whatever.
No matter what measurements you choose or if you choose not to measure at all, you know when you have accomplished something to be proud of. Anytime you feel you have made such an accomplishment, you can post about it in this forum and people will congratulate you for it. Or you can just smile and enjoy your acheivement privately. It just doesn't matter. It's all good.

cyclinfool

+1!

Road Fan

Just to simplify perhaps unconsionably, power to maintain a given speed scales faster than linearly, and the 5 hour rider had a higher average speed than the 6.5 hour rider. So the faster rider's watt-hours per mile (energy required to cover a distance) is greater than for the 6.5 hour rider, and the faster rider did more work than the slower rider.

Road "I can only do simple physics" Fan

DnvrFox

The factor you didn't mention was wind resistance. Wind resistance, everything else being equal, is a major difference in force requirements. Not only did the faster rider go faster, he did so with increased wind resistance, which does not increase arithmetically, but, instead, increases geometrically with speed.

crazyb

Same route of 20 miles. One rider completes it in 2 hours and another in one hour. My bet is the one hour rider got the better aerobic benefit.

maddmaxx 

Wind resistance is the only real difference. (ok, there's bearing drag and tire drag but they would be hard to add to the equation being so small). Work done however is moving x amount of mass over x amount of distance. The slower rider works less per minute but works longer so its a wash. As Dnvr points out, even the wind resistance would cancle out if it was a linear function but its not.

TrackGuy

Get a PowerMeter and report you efforts in Watts/Hour. That will take all of the conversion factors for headwinds, baggy pants, hills, weight of the equipment & cargo into account.

I'm sticking with miles, of which I did 85 today.

webist

That's how I read it. In fact, I'm thinking of giving myself extra credit for the food I carry along on a ride. After all, it's additional wieght even after I eat it.

cyclinfool

Max - I think you might be wrong on this point. Work is force times distance, this is true. However you need to apply more force to cover the distance at a higher speed due to the added wind drag. The force required to maintain velocity at higher speeds goes up as the square of the velocity. The power required to move that object goes up as a cube of the velocity. Power is an instantaneous quantity and energy is power integrated or summed up over time. Say a biker moving 10 miles per hour for 10 miles exerts X watts of power/hour for 1 hour. A biker moving at 20 miles per hour exerts 4X (neglecting all factors but wind resistance) of power for 30 minutes. The net effect is that the biker moving at 20 miles per hour expended 2 times the energy as teh 10mph biker. Now if the biker moving at 20 miles per hour had a more areodynamic position on the bike he would reduce his drag and decreases his power output.

I apologize for the geekieness

maddmaxx 

If I read the last bit about net effect in your post you state that the biker moving 20mph expends twice the energy of the 10mph rider. But the 10mph rider expends 1/2 the energy for twice as long for the same net energy expenditure. Thus the non linear function of the wind resistance remains the only difference in the equation.

There. I'll see your geekieness and raise you some nerdiness....

Tom Bombadil

Heck, I'm thrilled that I can go out and take a 25-30 mile ride, enjoy nature, not have any significant pain, get some exercise, and enjoy the total experience. Much like Solveg enjoys coasting, one of my favorite things to do is stopping. I love to stop and admire scenic views, stretch my legs, stop in small towns (can't hardly pass one by without stopping), watch birds, or assist someone (did that again tonight on my ride).

I usually average a stop every 4 miles. My longest segment ever ridden without stopping is just 10 miles.

It's a wonder I get any miles in at all. Even on the day I rode 64 miles, I stopped 15-16 times.

A perfect ride for me would be something around 35 miles on a bike trail that ran through 4 small towns and had pretty views of wetlands, rivers, farms, hills, etc. Stop in each town, once to have lunch, and then a stop between each town to admire the view. It would take at least 5 hours to complete the ride, but only about 3 in the saddle.

I'm hoping to get in about 5 such days before the end of October.

The number of miles is less important to me than the hours in the saddle, but they are related. When I get that many miles it, it feels like I had a good exercise. If I rode 3 hours at a slower pace, it would be a lesser experience for I just wouldn't have circled the pedals enough. Although there are days where 15, or even 12, miles is perfect for that day.

Whether or not someone else thinks that's an adequate workout doesn't matter much to me. Hearing of others accomplishments does motivate me to try to ride longer. I doubt I would have attempted anything over 20-25 miles if not for the 50+ forum. But I'm not dying to ride a century or turn 50 miles in 3 hours. But I wouldn't mind up'ing my performance by another 10%-15% - I could see more sights and visit more towns that way!

cyclinfool

Max, Almost. I was wrong as well on this - I looked it up again. It's been a long time since I looked at these equations.
This wiki link explans it pretty well: https://en.wikipedia.org/wiki/Drag_(physics)
Energy is power times time - you pay for electricity in KWatt - hours.
The Power to drive an object at a velocity V goes up as the cube of the velocity V^3, so the bike at 10mph is expending 1/8th the power as the 20mph biker for twice as long. Energy is power X time so his energy is 1/4, not 1/2 as I stated.
An example - Biker 1 traveling at 10 mph requires a 1KW of power output to maintain speed.
Biker 2 at 20mph requires 8KW of power (velocity cubed)
The bikers travel 10 miles.
1 KWatt - hour = 860 kcal
Biker 1 burns 860 kcal
Biker 2 burns 8 x 0.5 = 4KWatt-hour = 3440 kcal

Nerd alert - we are entering the zone of pure boredom.

maddmaxx 

Sorry, I was confining my observations to just "Work" done not energy expended. "Work" in the physics world has no time component. You can burn calories standing next to your bike or holding it over your head without accomplishing work, but for the sake of the simplistic comparison of miles ridden I thought we were just comparing work output. You are still moving Mass X from point Y to point Z. Therefor I stand by my statement that Wind drag is the only meaningful variable in the equation when calculating work done.

Big Paulie

Great topic...

maddmaxx 

Only if your a tongue in cheek sort of guy.

SaiKaiTai

I'm still puzzled by the point Yen is trying to make here.
If someone rides 20 miles in an hour -20mph by definition- and you do 20 miles in 2 hours -10mph- then you've done half as much in twice as long. That doesn't seem like double anything to me. If anything, it's a wash.

2manybikes

It's more than twice the work to make a bike go 20 compared to 10.

Yen put the big grin at the end of the post to say, it's a joke or it's just meant to be funny. The point is just to give us a smile or a laugh. I like it !

What is heavier a 3 lb. titanium frame, or a 3 lb. steel frame ? <- big grin meaning it's a joke

johnnyb

pdq 5oh,
Rolling resistance.....this is starting to get complicated.....ya think?

Presumably heart rate tracking measures combined result of effort (hills, rolling resistance, bike weight, etc. and yada) on the specific individual so miles may be what we measure by BUT there are so many different miles and the heart rate or Cardio is what we are after. Sorry I can't get TOO caught up in measuring. You know how it felt and it IS fun....but everyone gets some different buzz or need fulfilled from it. To each his/her own.

Oh...went to the doc today and blood pressure was 109/63 and they were impressed....along with the 20 lbs dropped. I REALLY enjoy riding !!! Such a rush when I get out there each time, get warmed up and get the cadence up.

J

shumacher

No, you have to adjust for dog years. Age * 7 = miles.

Thrifty1

An extremely important factor has been omitted.
It is ACCEPTED that red bikes are X times faster........ so a red bike rider expends X times less energy/work as riders on non-red (white) bikes for the same distance/time.