calorie burn walk vs jog

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Date: 23 Aug 2006 14:24:30
From: 40yearOLDrookie2exercise
Subject: calorie burn walk vs jog

My question is elementary,,,,

Does walking burn a similar amount of calories compared to jogging ,
when starting out with some sort of exercise to get in better shape and
drop 20 pounds ? I realize there are a number of other factors
involved. heart rate, blah blah blah

Just looking for the most simple answer please .

thanks :)

Date: 23 Aug 2006 16:23:44
From:
Subject: Re: calorie burn walk vs jog

40yearOLDrookie2exercise <labetteboy@yahoo.com > writes:
: My question is elementary,,,,

: Does walking burn a similar amount of calories compared to jogging ,

For an equal distance it doesn't matter. You can just cover the
distance quicker jogging.

: when starting out with some sort of exercise to get in better shape and
: drop 20 pounds ? I realize there are a number of other factors
: involved. heart rate, blah blah blah

Heart rate doesn't matter unless you want to actually live longer.
For fat burning all that matters is calories burned. Just do the
distance, no matter how long it takes.

: Just looking for the most simple answer please .

: thanks :)

For example, say you weigh 165 and you want to burn an extra 500
calories a day. Then you need to cover 4.4 miles. If you want to
burn 1000 calories, you need to cover 8.8 miles. This is a lot
faster jogging than walking, but who's got a watch?!

Larry

Date: 23 Aug 2006 18:36:28
From: oregonchick
Subject: Re: calorie burn walk vs jog

"40yearOLDrookie2exercise" <labetteboy@yahoo.com > wrote in message
news:1156368270.287566.57580@m73g2000cwd.googlegroups.com...
> My question is elementary,,,,
>
> Does walking burn a similar amount of calories compared to jogging ,
> when starting out with some sort of exercise to get in better shape and
> drop 20 pounds ? I realize there are a number of other factors
> involved. heart rate, blah blah blah
>
> Just looking for the most simple answer please .
>
> thanks :)

I'm no runner, but I've had to start from nothing before, and needing to
lose weight while starting completely unfit. Here is what I did. I started
with walking. You'd be amazed how much your heartrate goes up with vigorous
walking, especially if there are some hills, when you are really out of
shape. I walked around a local golf course that had a nice 2 miles
perimeter walk/jog path. I walked it every day. When that didn't feel hard
anymore, I threw in occasional sprints or jogs intermittently. When that
was easy, I joined the gym and started doing resistance training and other
types of intense cardio (like elliptical) because it was the start of fowl
weather and I'm a fair weather walker ;- )

Date: 23 Aug 2006 23:46:07
From:
Subject: Re: calorie burn walk vs jog

oregonchick <not_here@comcat.net > writes:

: "40yearOLDrookie2exercise" <labetteboy@yahoo.com > wrote in message
: news:1156368270.287566.57580@m73g2000cwd.googlegroups.com...
: > My question is elementary,,,,
: >
: > Does walking burn a similar amount of calories compared to jogging ,
: > when starting out with some sort of exercise to get in better shape and
: > drop 20 pounds ? I realize there are a number of other factors
: > involved. heart rate, blah blah blah
: >
: > Just looking for the most simple answer please .
: >
: > thanks :)

: I'm no runner, but I've had to start from nothing before, and needing to
: lose weight while starting completely unfit. Here is what I did. I started
: with walking. You'd be amazed how much your heartrate goes up with vigorous
: walking, especially if there are some hills, when you are really out of
: shape. I walked around a local golf course that had a nice 2 miles
: perimeter walk/jog path. I walked it every day. When that didn't feel hard
: anymore, I threw in occasional sprints or jogs intermittently. When that
: was easy, I joined the gym and started doing resistance training and other
: types of intense cardio (like elliptical) because it was the start of fowl
: weather and I'm a fair weather walker ;- )

Don't I know you from mkp, mkb?

Larry

Date: 26 Aug 2006 15:14:42
From: oregonchick
Subject: Re: calorie burn walk vs jog

<mcmahan@cup.hp.com > wrote in message news:44ed3d1f@usenet01.boi.hp.com...
> oregonchick <not_here@comcat.net> writes:
>
> : "40yearOLDrookie2exercise" <labetteboy@yahoo.com> wrote in message
> : news:1156368270.287566.57580@m73g2000cwd.googlegroups.com...
> :> My question is elementary,,,,
> :>
> :> Does walking burn a similar amount of calories compared to jogging ,
> :> when starting out with some sort of exercise to get in better shape and
> :> drop 20 pounds ? I realize there are a number of other factors
> :> involved. heart rate, blah blah blah
> :>
> :> Just looking for the most simple answer please .
> :>
> :> thanks :)
>
> : I'm no runner, but I've had to start from nothing before, and needing to
> : lose weight while starting completely unfit. Here is what I did. I
> started
> : with walking. You'd be amazed how much your heartrate goes up with
> vigorous
> : walking, especially if there are some hills, when you are really out of
> : shape. I walked around a local golf course that had a nice 2 miles
> : perimeter walk/jog path. I walked it every day. When that didn't feel
> hard
> : anymore, I threw in occasional sprints or jogs intermittently. When
> that
> : was easy, I joined the gym and started doing resistance training and
> other
> : types of intense cardio (like elliptical) because it was the start of
> fowl
> : weather and I'm a fair weather walker ;- )
>
>
> Don't I know you from mkp, mkb?

yep. mkb

Date: 23 Aug 2006 22:32:40
From: Doug Freese
Subject: Re: calorie burn walk vs jog

Date: 23 Aug 2006 15:04:50
From: runsrealfast
Subject: Re: calorie burn walk vs jog

rick++ wrote:

> If you compare equal mileage, then the total calories
> isnt that different for running or walking.

I can't walk as fast as my slowest run or what I would consider a jog.
So get simple anwser is running burns more. The best rule to follow is
the longer you work out for the more calories your going to burn.

john

Date: 23 Aug 2006 14:53:11
From: rick++
Subject: Re: calorie burn walk vs jog

This table calculates by time spent exercising.
Someone can run 2-3 times the distance in the same time
and that explains most of the increase.
If you compare equal mileage, then the total calories
isnt that different for running or walking.

Date: 24 Aug 2006 01:20:00
From: steve common
Subject: Re: calorie burn walk vs jog

"rick++" <rick303@hotmail.com > wrote:

>If you compare equal mileage, then the total calories
>isnt that different for running or walking.

Fair enough. The OP didn't mention constraints so I just assumed per given
time (I don't do training based on distance but on time).

Date: 24 Aug 2006 11:42:31
From: j
Subject: Re: calorie burn walk vs jog

steve common wrote:
> "rick++" <rick303@hotmail.com> wrote:
>
>
>>If you compare equal mileage, then the total calories
>>isnt that different for running or walking.
>
>
> Fair enough. The OP didn't mention constraints so I just assumed per given
> time (I don't do training based on distance but on time).

Or, taking the question around,
what is the energetic efficiency of walking (for a while, e.g. 3
minutes) at the same speed during a marathon ?

JF

Date: 24 Aug 2006 13:19:38
From: steve common
Subject: Re: calorie burn walk vs jog

j <j@ici.la > wrote:

>Or, taking the question around,
>what is the energetic efficiency of walking (for a while, e.g. 3
>minutes) at the same speed during a marathon ?

AFAIK, walking is more energy efficient per distance than jogging at paces
up to near your personal "crossover" ie where you naturally start breaking
into a run.

So if you can walk as fast as you can jog for any reason - lack of
training, weight, tiredness during an (ultra)endurance event (or as a base
strategy to prepare for future tiredness in an ultra event...), you're
probably better off walking a little, especially as it uses different
muscles = > gives your running muscles a breather.

FWIW I walked for about 20-30secs at each aid station (every 5k) during my
PB 2:55 marathon, mostly because of advice from "Saint" Serge Cottereau in
/Jogging International/ :oP Though I still don't know for sure if the
strategy optimised my time that day or wasted me a couple of minutes. I do
know that it was the "easiest" marathon I ever raced.

Date: 23 Aug 2006 21:46:40
From: Dot
Subject: Re: calorie burn walk vs jog

40yearOLDrookie2exercise wrote:

> My question is elementary,,,,
>
> Does walking burn a similar amount of calories compared to jogging ,
> when starting out with some sort of exercise to get in better shape and
> drop 20 pounds ? I realize there are a number of other factors
> involved. heart rate, blah blah blah
>
> Just looking for the most simple answer please .

For the same amt of time, running generally burns more than walking for
"normal" efforts. Power walking can burn more than easy running. And if
you start adding hills, yadda yadda yadda.

Just get out there doing something instead of worrying about numbers.

Dot

--
"Success is different things to different people"
-Bernd Heinrich in Racing the Antelope

Date: 23 Aug 2006 14:34:41
From: runsrealfast
Subject: Re: calorie burn walk vs jog

Date: 23 Aug 2006 23:32:09
From: steve common
Subject: Re: calorie burn walk vs jog

"40yearOLDrookie2exercise" <labetteboy@yahoo.com > wrote:

> My question is elementary,,,,
>
>Does walking burn a similar amount of calories compared to jogging ,
>when starting out with some sort of exercise to get in better shape and
>drop 20 pounds ? I realize there are a number of other factors
>involved. heart rate, blah blah blah
>
>Just looking for the most simple answer please .

Jogging burns more than walking.

Hint : go to www.google.com, type into the search box

calories jogging walking

Click on any of the links, this one for example
http://calorielab.com/burned/index.html

Date: 24 Aug 2006 05:52:15
From: rick++
Subject: Re: calorie burn walk vs jog

For health reasons, five hours of vigourous
walking a week is as good as three hours of jogging.

People run for other reasons- to save time geting healthy,
to race, and for the exhiliration.

Date: 24 Aug 2006 17:05:04
From: 40yearOLDrookie2exercise
Subject: Re: calorie burn walk vs jog

thanks very much for your info ,,,, thats the plan I intend to follow
as well, EXACLTY in fact.... thanks agian :)
oregonchick wrote:
> "40yearOLDrookie2exercise" <labetteboy@yahoo.com> wrote in message
> news:1156368270.287566.57580@m73g2000cwd.googlegroups.com...
> > My question is elementary,,,,
> >
> > Does walking burn a similar amount of calories compared to jogging ,
> > when starting out with some sort of exercise to get in better shape and
> > drop 20 pounds ? I realize there are a number of other factors
> > involved. heart rate, blah blah blah
> >
> > Just looking for the most simple answer please .
> >
> > thanks :)
>
> I'm no runner, but I've had to start from nothing before, and needing to
> lose weight while starting completely unfit. Here is what I did. I started
> with walking. You'd be amazed how much your heartrate goes up with vigorous
> walking, especially if there are some hills, when you are really out of
> shape. I walked around a local golf course that had a nice 2 miles
> perimeter walk/jog path. I walked it every day. When that didn't feel hard
> anymore, I threw in occasional sprints or jogs intermittently. When that
> was easy, I joined the gym and started doing resistance training and other
> types of intense cardio (like elliptical) because it was the start of fowl
> weather and I'm a fair weather walker ;- )

Date: 25 Aug 2006 15:20:57
From: rick++
Subject: Re: calorie burn walk vs jog

> Doesn't that depend on the weight of the person? A 200 lb person
> theoretically will burn twice the number of calories as a 100 lb person.

The rough rule is around 0.7 kcal per pound. People's metabolism
get a little more efficient as they get in shape and as they get older
and burn a little less.

Date: 25 Aug 2006 13:43:34
From: Don Kirkman
Subject: Re: calorie burn walk vs jog

It seems to me I heard somewhere that 40yearOLDrookie2exercise wrote in
article <1156368270.287566.57580@m73g2000cwd.googlegroups.com >:

> My question is elementary,,,,

>Does walking burn a similar amount of calories compared to jogging ,
>when starting out with some sort of exercise to get in better shape and
>drop 20 pounds ? I realize there are a number of other factors
>involved. heart rate, blah blah blah

>Just looking for the most simple answer please .

One rule of thumb is that, for most practical purposes, walking,
jogging, and fast running all burn about 100 calories **per mile**.
Obviously calories per hour will differ, and will differ slightly with
build, physical condition, course conditions, etc., etc.
--
Don Kirkman

Date: 25 Aug 2006 14:15:46
From: Beginning runner
Subject: Re: calorie burn walk vs jog

In article <99lue2t0ajd6ij2687bog4ginmlt873k6t@4ax.com >,
Don Kirkman <donsno2@wavecable.com > wrote:

> One rule of thumb is that, for most practical purposes, walking,
> jogging, and fast running all burn about 100 calories **per mile**.

Doesn't that depend on the weight of the person? A 200 lb person
theoretically will burn twice the number of calories as a 100 lb person.

Date: 25 Aug 2006 17:26:04
From:
Subject: Re: calorie burn walk vs jog

Beginning runner <bogus@invalid.com > writes:
: In article <99lue2t0ajd6ij2687bog4ginmlt873k6t@4ax.com >,
: Don Kirkman <donsno2@wavecable.com > wrote:

: > One rule of thumb is that, for most practical purposes, walking,
: > jogging, and fast running all burn about 100 calories **per mile**.

: Doesn't that depend on the weight of the person? A 200 lb person
: theoretically will burn twice the number of calories as a 100 lb person.

YES! You actually burn about .7 Calories per pound per mile.

To burn 100 Calories per mile you would have to weigh 143 lbs.

A 200 lb person burns 140 Caloreis per mile.

A 100 lb person burns 70 Calories per mile

Larry

Date: 26 Aug 2006 16:12:29
From: Mark and Christine
Subject: Re: calorie burn walk vs jog

mcmahan@cup.hp.com wrote in
news:44ef870c@usenet01.boi.hp.com:

> Beginning runner <bogus@invalid.com> writes:
>: In article <99lue2t0ajd6ij2687bog4ginmlt873k6t@4ax.com>,
>: Don Kirkman <donsno2@wavecable.com> wrote:
>
>:> One rule of thumb is that, for most practical purposes,
>:> walking, jogging, and fast running all burn about 100
>:> calories **per mile**.
>

And this is the crux - A calorie (or Calorie for what is being
discussed above) is a measure of energy expenditure, not
power, which involves energy expenditure over time.

It takes the same energy to move the same weight (mass) the
same distance. That is a basic tenant of the definition. If
the human body had the same energy expenditure efficiency at
all expenditure rates, then you would use the same energy
going the same distance whether you walked or ran.

Unfortunately, for various reasons, as the body speeds up its
efficiency goes down, therefore you use more energy over the
same distance as you go faster.

As your physical conditioning improves this difference will
decrease, but never go away.

Christine

Date: 27 Aug 2006 19:07:40
From: Phil M.
Subject: Re: calorie burn walk vs jog

donsno2@wavecable.com wrote:

> One rule of thumb is that, for most practical purposes, walking,
> jogging, and fast running all burn about 100 calories **per mile**.
> Obviously calories per hour will differ, and will differ slightly with
> build, physical condition, course conditions, etc., etc.

I miss Sam. http://tinyurl.com/7kz5x

--
Phil M.

Date: 28 Aug 2006 11:32:48
From: Doug Freese
Subject: Re: calorie burn walk vs jog

"Phil M." <pmarg@charter.net > wrote in message
news:Xns982C99D2B2957seilogramp@216.77.188.18...
> donsno2@wavecable.com wrote:
>
> I miss Sam. http://tinyurl.com/7kz5x

Me too! Does anyone know if Sam posting on any other forums??

-DF

Date: 28 Aug 2006 15:57:20
From: Dot
Subject: Re: calorie burn walk vs jog

Doug Freese wrote:
> "Phil M." <pmarg@charter.net> wrote in message
> news:Xns982C99D2B2957seilogramp@216.77.188.18...
>
>>donsno2@wavecable.com wrote:
>>
>>I miss Sam. http://tinyurl.com/7kz5x
>
>
> Me too! Does anyone know if Sam posting on any other forums??
>
> -DF
>
>
Yes - a couple that I'm aware of. Try RW and RT - usually in the
training forums is where I see him on a fairly regular basis. Look for
the science poster. :) Since RW messed things up in June, he's about
the only regular science poster left.

Dot

--
"Success is different things to different people"
-Bernd Heinrich in Racing the Antelope

Date: 28 Aug 2006 15:07:06
From: Michael
Subject: Re: calorie burn walk vs jog

Although it was believed that distance determined the number of calories
burned, apparently new research has determined that running burns
50-100% more calories (depending on whether you're measuring total or
net calories).

Here's a link to an article by Amby Burfoot that explains this:

http://www.runnersworld.com/article/0,7120,s6-242-304-311-8402-0,00.html

40yearOLDrookie2exercise wrote:
> My question is elementary,,,,
>
> Does walking burn a similar amount of calories compared to jogging ,
> when starting out with some sort of exercise to get in better shape and
> drop 20 pounds ? I realize there are a number of other factors
> involved. heart rate, blah blah blah
>
> Just looking for the most simple answer please .
>
> thanks :)
>

Date: 12 Sep 2006 15:40:29
From: Robert Grumbine
Subject: Re: calorie burn walk vs jog

In article <uEDIg.73035$u11.23931@tornado.ohiordc.rr.com >,
Michael <news@bigtoes.com > wrote:
>Although it was believed that distance determined the number of calories
>burned, apparently new research has determined that running burns
>50-100% more calories (depending on whether you're measuring total or
>net calories).
>
>Here's a link to an article by Amby Burfoot that explains this:
>
>http://www.runnersworld.com/article/0,7120,s6-242-304-311-8402-0,00.html

Darn. Looks like I'll have to update what I tell people. But
it looks like a reasonable test.

Thanks for the info.

--
Robert Grumbine http://www.radix.net/~bobg/ Science faqs and amateur activities notes and links.
Sagredo (Galileo Galilei) "You present these recondite matters with too much
evidence and ease; this great facility makes them less appreciated than they
would be had they been presented in a more abstruse manner." Two New Sciences

Date: 12 Sep 2006 20:16:58
From: Donovan Rebbechi
Subject: Re: calorie burn walk vs jog

On 2006-09-12, Robert Grumbine <bobg@radix.net > wrote:
> In article <uEDIg.73035$u11.23931@tornado.ohiordc.rr.com>,
> Michael <news@bigtoes.com> wrote:
>>Although it was believed that distance determined the number of calories
>>burned, apparently new research has determined that running burns
>>50-100% more calories (depending on whether you're measuring total or
>>net calories).
>>
>>Here's a link to an article by Amby Burfoot that explains this:
>>
>>http://www.runnersworld.com/article/0,7120,s6-242-304-311-8402-0,00.html
>
> Darn. Looks like I'll have to update what I tell people. But
> it looks like a reasonable test.

My knee-jerk reaction was to doubt this, but I checked in my physiology book which
asserts that what Burfoot is saying is not only true, it's well established.

Perhaps a possible source of the confusion is the fact that at the "break point"
where one switches from walking to running (usually about 5mph), economy is the
same for both. So maybe this causes the public to believe that both burn about
the same amount of fuel.

However, as one drops below 5mph, walking rapidly becomes more economical, that is,
one burns less calories per unit distance.

So if one plots VO2 for walking in the range of "normal" walking speeds, 2mph-5mph
for example, the graph is distinctly concave-up, whereas the analogous graph for
endurance running speeds (say 5-10mph) is more or less linear.

The end result of this is that it's reasonable to assume that energy cost of a
run is (more or less) directly proportional to distance, but the same is not
true of walking. To get a reasonable burn rate from walking, I'd suggest
wearing a heart rate monitor and maintaining a heart rate comparable to easy
endurance running (btw, it is surprisingly difficult to achieve this by walking
on a level surface!)

Cheers,
--
Donovan Rebbechi
http://pegasus.rutgers.edu/~elflord/

Date: 13 Sep 2006 01:19:08
From: Phil M.
Subject: Re: calorie burn walk vs jog

abuse@aol.com wrote:

> To get a reasonable burn rate from walking, I'd suggest
> wearing a heart rate monitor and maintaining a heart rate comparable
> to easy endurance running (btw, it is surprisingly difficult to
> achieve this by walking on a level surface!)

When I was injured and was only walking I found it difficult to get close
to 60% max. At 14:30/mi it is a nice trot for the dog, but for me it was a
very fast walk.

--
Phil M.

Date: 22 Sep 2006 18:02:29
From: Robert Grumbine
Subject: Re: calorie burn walk vs jog

In article <slrnege5dq.g0v.abuse@panix2.panix.com >,
Donovan Rebbechi <abuse@aol.com > wrote:

[trim]

>The end result of this is that it's reasonable to assume that energy cost of a
>run is (more or less) directly proportional to distance, but the same is not
>true of walking. To get a reasonable burn rate from walking, I'd suggest
>wearing a heart rate monitor and maintaining a heart rate comparable to easy
>endurance running (btw, it is surprisingly difficult to achieve this by walking
>on a level surface!)

I've found an odd thing in this vein. Or maybe it is just me who is odd.
That is, if I just go out and start walking quickly (5 mph or better),
my pulse doesn't break about 120 (even after an hour of the pace).
On the other hand, if I first jog enough to get my pulse over 150, then
walking will keep it over 140 as long as I keep the pace up some (and
4.5 mph is enough to do that).

Definite hysteresis effect. Dunno why. At my natural (optimal)
walking pace, 16 min/mile, I can go for a hour and the pulse won't
break 90.

--
Robert Grumbine http://www.radix.net/~bobg/ Science faqs and amateur activities notes and links.
Sagredo (Galileo Galilei) "You present these recondite matters with too much
evidence and ease; this great facility makes them less appreciated than they
would be had they been presented in a more abstruse manner." Two New Sciences

Date: 12 Sep 2006 11:32:36
From: rick++
Subject: Re: calorie burn walk vs jog

Its not clear from the article if they tested these possible variables:

(1) Optimal pace. I'd think you are less efficient running/walking
slowly or very fast.

(2) Experience in an exercise. I found the first five years of
running
the poulds stayed off easily. But evenetually I got used to it and
was able to gain weight again. I assume I was much more efficient
at covering distance after a few years than initially.

Date: 12 Sep 2006 20:09:01
From: Donovan Rebbechi
Subject: Re: calorie burn walk vs jog

On 2006-09-12, rick++ <rick303@hotmail.com > wrote:
> Its not clear from the article if they tested these possible variables:
>
> (1) Optimal pace. I'd think you are less efficient running/walking
> slowly or very fast.

At least for walking, this is well-known: the graph is rapidly concave-up. That's
why a good athlete walking at VO2 max can only manage a little under 6 minutes per
mile. The break-even point is about 5mph (where walking economy = running economy).

At most endurance running speeds, VO2 vs speed is more or less linear.

BTW, this article is not all that surprising. It is apparently well known (by
researchers though not the public unfortuantely) that running burns more than
walking.

> (2) Experience in an exercise. I found the first five years of
> running the poulds stayed off easily.

It improves, but top racewalkers still burn a ton of fuel.

> But evenetually I got used to it and was able to gain weight again.

Well, you have to stop losing weight eventually! Maintenance calories and caloric intake
converge one way or another. Usually because you weigh less and and sometimes because
you may have to eat more to avoid wasting away.

> I assume I was much more efficient at covering distance after a few years
> than initially.

I suspect that this has very little to do with it. For most runners, both increases in
training time and increases in VO2 should trump gains in economy.

Cheers,
--
Donovan Rebbechi
http://pegasus.rutgers.edu/~elflord/

Date: 13 Sep 2006 10:36:10
From: Ed Prochak
Subject: Re: calorie burn walk vs jog

Robert Grumbine wrote:
> In article <uEDIg.73035$u11.23931@tornado.ohiordc.rr.com>,
> Michael <news@bigtoes.com> wrote:
> >Although it was believed that distance determined the number of calories
> >burned, apparently new research has determined that running burns
> >50-100% more calories (depending on whether you're measuring total or
> >net calories).
> >
> >Here's a link to an article by Amby Burfoot that explains this:
> >
> >http://www.runnersworld.com/article/0,7120,s6-242-304-311-8402-0,00.html
>
> Darn. Looks like I'll have to update what I tell people. But
> it looks like a reasonable test.
>
> Thanks for the info.
>

yes interesting article. But I have two comments about it:

First, I noticed the calorie count was still for both men and women
around 100.
(for men the average between 124 and 88 is 106,
and for women between 105 and 74 is nearly 90)
So to a first approximation, I think the 100 figure is okay.
But that's just because it is easy to remenber, and a matter of
opinion.
IOW always say 100 per mile with the added YMMV caveat

Second. I am not sure I agree with the Bouncing theory of the
difference between running and walking. In fact I was trying during
yesterdays run to figure this out and a Car Talk puzzler suggested the
answer. Consider a car going down the road. the portion of the tire
touching the road is travelling at what speed? Zero (it is touching the
ground and for that brief moment is not moving relative to the ground)
The portion of the tire on the exact opposite side of the wheel is
travelling at what speed? Well, twice the speed of the car, again for a
brief moment. Now that ignores all kinds of rotational movement, BUT
think about what happens to your feet and legs.

One leg is coming off the ground and moving backward. Your body (center
of gravity) is moving forward at some speed, so that leg as it comes up
must be accellerated not just to catch up to your body, but past it,
basically twice the speed of your body. After it gets in front, and
before it touches the ground again, the motion in that leg must be
decellerated and started to move backward.

Basically it is my contention that this continuous movement forward and
then backward of our legs is where the energy is burned.

The energy involved in moving the body, ie the center of gravity, is:
the energy to initially get the body moving horizontally
(no gravity involved here. this is a onetime cost cause bodies in
motion, stay in motion)
the energy to overcome wind resistance
(which is relatively small, even for sprinters)
the energy of moving the center of gravity up and down
(is small unless you have a Large bounce, but most runners learn to
run so the body stays level with little bounce)

Actually some wind resistance will be much higher on the legs since at
least postions of their motion involve moving forward faster than the
rest of the body (Hm: if a sprinter runs about 30miles per hour, is his
foot movuing forward at over 60MPH? wow!) So if the main energy cost is
overcoming wind resistance, then it's the wind on the legs that causes
the highest portion of this cost.

If there is a gravity component to the energy expeneded, then it is
that as we move our legs forward, we also raise them up. Does that move
our body (center of gravity) down? I would argue , no not much. While
we raise our back leg for the forward swing, we also extend our front
leg to ready for touching the ground. We don't get that extension for
free, because we don't let gravity straighten it out. (that might take
too long before we need to have our foot back on the ground.)

The basic premise was from musings during my run yesterday. Was I
dillusional, or does this idea have some merit?

Ed

Date: 15 Sep 2006 18:04:27
From: Donovan Rebbechi
Subject: Re: calorie burn walk vs jog

On 2006-09-13, Ed Prochak <edprochak@gmail.com > wrote:

> Basically it is my contention that this continuous movement forward and
> then backward of our legs is where the energy is burned.

Most of the energy goes into vertical motion (~50% maybe), though a substantial
portion is forward + backward movement (more like 25%). At least that's what I
recall from reading papers/abstracts on this.

> The energy involved in moving the body, ie the center of gravity, is:
> the energy to initially get the body moving horizontally
> (no gravity involved here. this is a onetime cost cause bodies in
> motion, stay in motion)
> the energy to overcome wind resistance
> (which is relatively small, even for sprinters)
> the energy of moving the center of gravity up and down
> (is small unless you have a Large bounce, but most runners learn to
> run so the body stays level with little bounce)

The body doesn't quite stay level. At 180 foot falls per minute, the center
of mass drops 0.5 * 9.8 * ( 1/12 - t/2 )^2 where t is ground contact time.
If t was zero, that would be about 14cm per footfall.

I get about 247 kcal per hour of mechanical work from that for someone who
weighs 70kg. The skeleto-muscular system isn't 100% efficient, it's only about
25% efficient, so that gives close to 1000cal/hr. The numbers drop quite a bit
as you add ground contact time, of course.

> If there is a gravity component to the energy expeneded, then it is
> that as we move our legs forward, we also raise them up. Does that move
> our body (center of gravity) down?

The only way to move our center of gravity is to push off the ground.

> I would argue , no not much. While
> we raise our back leg for the forward swing, we also extend our front
> leg to ready for touching the ground. We don't get that extension for
> free, because we don't let gravity straighten it out.

We still get that energy back when we lower the leg back down.

> (that might take
> too long before we need to have our foot back on the ground.)
>
> The basic premise was from musings during my run yesterday. Was I
> dillusional, or does this idea have some merit?

I think you're underestimating the amount of work involved in vertical motion.

Cheers,
--
Donovan Rebbechi
http://pegasus.rutgers.edu/~elflord/

Date: 15 Sep 2006 17:43:38
From: Robert Grumbine
Subject: Re: calorie burn walk vs jog

In article <1158168970.177508.287340@m73g2000cwd.googlegroups.com >,
Ed Prochak <edprochak@gmail.com > wrote:
>
>Robert Grumbine wrote:
>> In article <uEDIg.73035$u11.23931@tornado.ohiordc.rr.com>,
>> Michael <news@bigtoes.com> wrote:
>> >Although it was believed that distance determined the number of calories
>> >burned, apparently new research has determined that running burns
>> >50-100% more calories (depending on whether you're measuring total or
>> >net calories).
>> >
>> >Here's a link to an article by Amby Burfoot that explains this:
>> >
>> >http://www.runnersworld.com/article/0,7120,s6-242-304-311-8402-0,00.html
>>
>> Darn. Looks like I'll have to update what I tell people. But
>> it looks like a reasonable test.
>>
>> Thanks for the info.
>
>yes interesting article. But I have two comments about it:
>
>First, I noticed the calorie count was still for both men and women
>around 100.
>(for men the average between 124 and 88 is 106,
>and for women between 105 and 74 is nearly 90)
>So to a first approximation, I think the 100 figure is okay.
>But that's just because it is easy to remenber, and a matter of opinion.
>IOW always say 100 per mile with the added YMMV caveat.

Yes, no biggie. I already knew the figure was variable. Mine,
for jogging pace, inferred from heat loss, is about 125/mile.

>Second. I am not sure I agree with the Bouncing theory of the
>difference between running and walking.

[snip example of need to accelerate legs from their stop position
(touchdown) to full forward speed]

>Basically it is my contention that this continuous movement forward and
>then backward of our legs is where the energy is burned.

It is, but this applies equally to walking. The legs have to
accelerate, same as for running, from their instantaneous (actually
for a significant period -- hundredths of a second) stop.

For both running and walking, the resistence of the 'relaxing'
muscle to being extended by the contracting one is a significant
energy sink. (How significant seems to be a question.) The
world being a generally nonlinear place, the larger range of motion
required in running vs. walking argues for greater energy expenditure
per step. (On the other hand, fewer steps, so the net is ...?)

>The energy involved in moving the body, ie the center of gravity, is:
>the energy to initially get the body moving horizontally
> (no gravity involved here. this is a onetime cost cause bodies in
>motion, stay in motion)
>the energy to overcome wind resistance
> (which is relatively small, even for sprinters)
>the energy of moving the center of gravity up and down
> (is small unless you have a Large bounce, but most runners learn to
>run so the body stays level with little bounce)

Well, the fraction of energy required to move the center of gravity
up which is lost on impact with the ground. With proper form, and
with good springy muscles, much of this energy is transferred into the
next upward motion. Lots of little bounces (short steps) can easily
equal fewer larger ones.

>Actually some wind resistance will be much higher on the legs since at
>least postions of their motion involve moving forward faster than the
>rest of the body (Hm: if a sprinter runs about 30miles per hour, is his
>foot movuing forward at over 60MPH? wow!) So if the main energy cost is
>overcoming wind resistance, then it's the wind on the legs that causes
>the highest portion of this cost.

Top sprinter speeds (fastest 10 meters) are about 27 mph, with 22 being
a more sustained average (10 m/s).

But don't get too attached to your wheel analogy. While we do refer
to 'having wheels', the mechanics of running are different.

The force of wind resistence is rho*Cd*A*u^2, where rho is the density
of the air, A is the area presented to the wind, u is the speed, and
Cd is the coefficient of drag. rho is a constant for torso and leg,
so we can ignore that. But what is the area? Legs, particularly
distance runner legs, are fairly narrow side to side (front to back,
on the other hand, there's significant size). Consequently, there's
little area presented even if the whole leg were moving at the elevated
speed.

Further, the drag on an ellipsoid with its long axis perpendicular
to the flow is relatively low, as compared to shoving a rectangular
plate (torso) through the same flow. So Cd is probably (I could look
it up eventually) 5-10 times smaller, and A is also a factor of several
smaller. Even if the whole leg were moving forward twice as fast as
the torso (which it obviously can't be as your hip requires zero
relative motion), then, the drag force is substantially less on
the legs than the torso.

>If there is a gravity component to the energy expeneded, then it is
>that as we move our legs forward, we also raise them up. Does that move
>our body (center of gravity) down? I would argue , no not much. While
>we raise our back leg for the forward swing, we also extend our front
>leg to ready for touching the ground. We don't get that extension for
>free, because we don't let gravity straighten it out. (that might take
>too long before we need to have our foot back on the ground.)
>
>The basic premise was from musings during my run yesterday. Was I
>dillusional, or does this idea have some merit?

The energetics of running are well worth some musing. I have some
notions suitable for a bit of lab work (or taking advantage of
someone else's lab work -- the required measurements have been
taken many times, somewhere or other) because of it. When all is
said and done, though, running is still a matter of getting one
foot in front of the other regularly.

--
Robert Grumbine http://www.radix.net/~bobg/ Science faqs and amateur activities notes and links.
Sagredo (Galileo Galilei) "You present these recondite matters with too much
evidence and ease; this great facility makes them less appreciated than they
would be had they been presented in a more abstruse manner." Two New Sciences

Date: 13 Sep 2006 13:13:56
From:
Subject: Re: calorie burn walk vs jog

You dont lose weight exercising. Stop eating like a pig. The advantage
of jogging is that you get a high which is much better than the high
you get eating.

40yearOLDrookie2exercise wrote:
> My question is elementary,,,,
>
> Does walking burn a similar amount of calories compared to jogging ,
> when starting out with some sort of exercise to get in better shape and
> drop 20 pounds ? I realize there are a number of other factors
> involved. heart rate, blah blah blah
>
> Just looking for the most simple answer please .
>
> thanks :)

Date: 13 Sep 2006 11:19:54
From: rick++
Subject: Re: calorie burn walk vs jog

Yet another description of the study at:

http://www.nytimes.com/2006/09/12/health/nutrition/12brody.html

How many of these caveats did the study actually measure
with a caliometer? (I believe the most common caliometer
is measuring CO2 in breath)

Also he disses treadmills in this article.