Re: what constitutes enough exercise?

[Guest guest]

In a message dated 10/4/04 10:04:51 PM Eastern Daylight Time, jnovick@... writes:

exercise capacity may be a more powerful predictor of mortality than other established risk factors for cardiovascular disease

Thanks. What do you suppose the mechanism(s) for the protective effect of exercise might be?

also, as to:

>"had multivariate relative risks of 0.90, 0.81, 0.80, and 0.81, respectively "

In the study I cited, "Walking Compared with Vigorous Exercise...", the effect shown under multivariate analysis was similar (1.00, 0.89, 0.81, 0.78, and 0.72), and also is *less* than the relative risks of 1.00, 0.73, 0.69, 0.68, and 0.47

Why does multivariate analysis give different figures than the relative risk analysis?

--

Ken

[Guest guest]

(Myers J, Prakash M, Froelicher V, Do D, Partington S, Atwood JE. Exercise

capacity and mortality among men referred for exercise testing. N Engl J Med

2002;346:793-801)

" showed that each 1-MET increase in exercise capacity conferred a 12 percent

improvement in survival ....... exercise capacity may be a more powerful

predictor of mortality than other established risk factors for cardiovascular

disease "

the best results (longevity) was in the highest MEt group (>8 METS) which is

quite a " high " level of intensity/exercise.

Title: Physical activity and coronary heart disease in men: The Harvard Alumni

Health Study.

Author: Sesso HD , Paffenbarger RS , Lee IM

Source: Circulation, 102(9): 975-80 2000

Abstract: BACKGROUND: The quantity and intensity of physical activity required

for the primary prevention of coronary heart disease (CHD) remain unclear.

Therefore, we examined the association of the quantity and intensity of physical

activity with CHD risk and the impact of other coronary risk factors. METHODS

AND RESULTS: We followed 12 516 middle-aged and older men (mean age 57.7 years,

range 39 to 88 years) from 1977 through 1993. Physical activity was assessed at

baseline in kilojoules per week (4.2 kJ=1 kcal) from blocks walked, flights

climbed, and participation in sports or recreational activities. During

follow-up, 2,135 cases of incident CHD, including myocardial infarction, angina

pectoris, revascularization, and coronary death, occurred. Compared with men

expending <2,100 kJ/wk, men expending 2,100 to 4,199, 4,200 to 8,399, 8,400 to

12,599, and >/=12,600 kJ/wk had multivariate relative risks of 0.90, 0.81, 0.80,

and 0.81, respectively (P: for trend=0.003). When we considered the independent

effects of specific physical activity components, only total sports or

recreational activities (P: for trend=0.042) and vigorous activities (P: for

trend=0.02) were inversely associated with the risk of CHD. These associations

did not differ within subgroups of men defined by coronary risk factors.

Finally, among men with multiple coronary risk factors, those expending >/=4,200

kJ/wk had reduced CHD risk compared with men expending <4,200 kJ/wk.

CONCLUSIONS: Total physical activity and vigorous activities showed the

strongest reductions in CHD risk. Moderate and light activities, which may be

less precisely measured, showed nonsignificant inverse associations. The

association between physical activity and a reduced risk of CHD also extends to

men with multiple coronary risk factors.

From McArdle Katch & Katch, EXERCISE PHYSIOLOGY: Energy, Nutrition and Human

Performance

" Research concerning the lifestyles and exercise habits or 17,000 Harvard

alumni, who enetered college between 1916 and 1950 gives strgon evidence that

moderate aerobic exercise, equivalent to jogging about 3 miles a day, promotes

good health and may actually add years to life. Regular exercise countered the

life-shortening effects of cigarette smoking and excess body mass. Even for

people with high BP, those who exercised regularly reduced their death rate by

one -half. Genetic tendencies toward an early death were countered by regular

exercise. ......... From the perspective of energy expenditure, the life

expectancy of harvard alumni increased steadily from an energy expenditure of

500 kcal per week - 3500 kcal; this was equivalent to 6 to 8 hours of

" strenuous " weekly exercise. In addition, active men lives an average of 1-2

years longer then sedentary classmates. Beyond weekly exercise of 3500 kcal,

there were NO ADDITIONAL health of longevity benefits. When exercise was

carried to extremes, the men had higher death rates than more moderately active

colleagues.

[Guest guest]

Hi folks:

What is interesting about the first study noted by Jeff below, is

that the apparent protective effect, even for those expending more

than 12,600 kj/week on exercise, is only a reduction of 20%. And

that effect is apparently no greater than the benefit from 4,200 -

8,400 kj/week.

This seems to argue in favor of the view that the benefits of

exercise are modest, and that modest to moderate amounts of it will

reap all the benefits that are to be had from exercise.

But there is another possible issue that may be highly relevant to us

here. What kind of lives did the subjects in this study lead,

besides their exercising? It is likely that they were much like the

rest of the population - not entirely a healthy 'lifestyle'.

Although the fact that they took exercise suggests they may have been

more health-conscious than average.

So, perhaps the explanation for the demonstrated benefit of exercise

shown in these studies is that it can reverse some (but not a heck of

a lot, apparently) of the effects of poor nutrition. For example, I

believe cholesterol levels are considerably reduced after exercise,

as if it gets burnt off in the process of exercising.

But what if your LDL is 50 before you even get around to thinking

about exercising? Will you see any CHD benefit from exercise? I

rather doubt it. But I assume that if there still is a benefit, it

would be less than the 20% shown in the study. Do we know the

answer? Given the CHD risk profiles of people on CR, can we

reasonably expect to see further CHD benefit from exercise?

Clearly, in old age, in addition to clean arteries, one also will

need sufficent strength, endurance and flexibility to do the things

one would like to do. Like take a five mile hike across the hills on

a beautiful spring morning if one feels in the mood. One will not

acquire that capacity sitting in a chair watching TV. But how much

exercise does one really need to get it? Hopefully jogging one mile

once a week will do it ; ^ )))

But I am interested in evidence indicating otherwise.

Rodney.

--- In , " Jeff Novick " <jnovick@p...>

wrote:

> (Myers J, Prakash M, Froelicher V, Do D, Partington S, Atwood JE.

Exercise capacity and mortality among men referred for exercise

testing. N Engl J Med 2002;346:793-801)

>

> " showed that each 1-MET increase in exercise capacity conferred a

12 percent improvement in survival ....... exercise capacity may be

a more powerful predictor of mortality than other established risk

factors for cardiovascular disease "

>

> the best results (longevity) was in the highest MEt group (>8 METS)

which is quite a " high " level of intensity/exercise.

>

> Title: Physical activity and coronary heart disease in men: The

Harvard Alumni Health Study.

> Author: Sesso HD , Paffenbarger RS , Lee IM

> Source: Circulation, 102(9): 975-80 2000

>

> Abstract: BACKGROUND: The quantity and intensity of physical

activity required for the primary prevention of coronary heart

disease (CHD) remain unclear. Therefore, we examined the association

of the quantity and intensity of physical activity with CHD risk and

the impact of other coronary risk factors. METHODS AND RESULTS: We

followed 12 516 middle-aged and older men (mean age 57.7 years, range

39 to 88 years) from 1977 through 1993. Physical activity was

assessed at baseline in kilojoules per week (4.2 kJ=1 kcal) from

blocks walked, flights climbed, and participation in sports or

recreational activities. During follow-up, 2,135 cases of incident

CHD, including myocardial infarction, angina pectoris,

revascularization, and coronary death, occurred. Compared with men

expending <2,100 kJ/wk, men expending 2,100 to 4,199, 4,200 to 8,399,

8,400 to 12,599, and >/=12,600 kJ/wk had multivariate relative risks

of 0.90, 0.81, 0.80, and 0.81, respectively (P: for trend=0.003).

When we considered the independent effects of specific physical

activity components, only total sports or recreational activities (P:

for trend=0.042) and vigorous activities (P: for trend=0.02) were

inversely associated with the risk of CHD. These associations did not

differ within subgroups of men defined by coronary risk factors.

Finally, among men with multiple coronary risk factors, those

expending >/=4,200 kJ/wk had reduced CHD risk compared with men

expending <4,200 kJ/wk. CONCLUSIONS: Total physical activity and

vigorous activities showed the strongest reductions in CHD risk.

Moderate and light activities, which may be less precisely measured,

showed nonsignificant inverse associations. The association between

physical activity and a reduced risk of CHD also extends to men with

multiple coronary risk factors.

>

>

>

> From McArdle Katch & Katch, EXERCISE PHYSIOLOGY: Energy,

Nutrition and Human Performance

>

> " Research concerning the lifestyles and exercise habits or 17,000

Harvard alumni, who enetered college between 1916 and 1950 gives

strgon evidence that moderate aerobic exercise, equivalent to jogging

about 3 miles a day, promotes good health and may actually add years

to life. Regular exercise countered the life-shortening effects of

cigarette smoking and excess body mass. Even for people with high

BP, those who exercised regularly reduced their death rate by one -

half. Genetic tendencies toward an early death were countered by

regular exercise. ......... From the perspective of energy

expenditure, the life expectancy of harvard alumni increased steadily

from an energy expenditure of 500 kcal per week - 3500 kcal; this was

equivalent to 6 to 8 hours of " strenuous " weekly exercise. In

addition, active men lives an average of 1-2 years longer then

sedentary classmates. Beyond weekly exercise of 3500 kcal, there

were NO ADDITIONAL health of longevity benefits. When exercise was

carried to extremes, the men had higher death rates than more

moderately active colleagues.

[Guest guest]

I just can believe that the exercise benefits can be separated so accurately, realizing that some people cannot or do not exercise due to other factors. One hour is not that much exercise for a Harvard alumni, eg, but it might be a lot for a person working 2 jobs, already.

These articles report the analysis of a specific set of people.

One of the things I noticed in the cardio's office, is the patients there, were not me. They were sickies, most not educated, truckdrivers, manual labor types. Some younger by 10 years (like 55yo), unable to do a treadmill stress test.

There's an increasing number of coronary bypasses on young people. Are those the children of wealthy folks? Wealthy enough to supply an abundance of the wrong foods, perhaps. ALL my gchildren except one are thin. The one is half German as in mother from Germany. Her two sibs are thin. They have eaten the same crap that other children eat, and get no more than the average exercise. So I think there's a major element from genetics.

Now at age, their gparents are fat (or dead), as in 200 -250 # males, 150 - 225# females. Working HARD at it, my wife and I are 150#, 175#.

Certainly exercise plays a role, but it's hard for me to say run 3 miles per day to avoid heart disease. I judge by what I need to keep BP down, ie, 3 mile walk, two maybe three times per week. But not to keep weight down - only calorie control will do that.

Regards.

----- Original Message -----

From: bpinfo@...

Sent: Monday, October 04, 2004 9:34 PM

Subject: Re: [ ] what constitutes enough exercise?

In a message dated 10/4/04 10:04:51 PM Eastern Daylight Time, jnovick@... writes:

exercise capacity may be a more powerful predictor of mortality than other established risk factors for cardiovascular diseaseThanks. What do you suppose the mechanism(s) for the protective effect of exercise might be?also, as to:>"had multivariate relative risks of 0.90, 0.81, 0.80, and 0.81, respectively "In the study I cited, "Walking Compared with Vigorous Exercise...", the effect shown under multivariate analysis was similar (1.00, 0.89, 0.81, 0.78, and 0.72), and also is *less* than the relative risks of 1.00, 0.73, 0.69, 0.68, and 0.47Why does multivariate analysis give different figures than the relative risk analysis?-- Ken

[Guest guest]

" Jogging one mile a week will do it " ..

What do you think a one mile a week jog will accomplish?

> > (Myers J, Prakash M, Froelicher V, Do D, Partington S, Atwood JE.

> Exercise capacity and mortality among men referred for exercise

> testing. N Engl J Med 2002;346:793-801)

> >

> > " showed that each 1-MET increase in exercise capacity conferred a

> 12 percent improvement in survival ....... exercise capacity may be

> a more powerful predictor of mortality than other established risk

> factors for cardiovascular disease "

> >

> > the best results (longevity) was in the highest MEt group (>8 METS)

> which is quite a " high " level of intensity/exercise.

> >

> > Title: Physical activity and coronary heart disease in men: The

> Harvard Alumni Health Study.

> > Author: Sesso HD , Paffenbarger RS , Lee IM

> > Source: Circulation, 102(9): 975-80 2000

> >

> > Abstract: BACKGROUND: The quantity and intensity of physical

> activity required for the primary prevention of coronary heart

> disease (CHD) remain unclear. Therefore, we examined the association

> of the quantity and intensity of physical activity with CHD risk and

> the impact of other coronary risk factors. METHODS AND RESULTS: We

> followed 12 516 middle-aged and older men (mean age 57.7 years, range

> 39 to 88 years) from 1977 through 1993. Physical activity was

> assessed at baseline in kilojoules per week (4.2 kJ=1 kcal) from

> blocks walked, flights climbed, and participation in sports or

> recreational activities. During follow-up, 2,135 cases of incident

> CHD, including myocardial infarction, angina pectoris,

> revascularization, and coronary death, occurred. Compared with men

> expending <2,100 kJ/wk, men expending 2,100 to 4,199, 4,200 to 8,399,

> 8,400 to 12,599, and >/=12,600 kJ/wk had multivariate relative risks

> of 0.90, 0.81, 0.80, and 0.81, respectively (P: for trend=0.003).

> When we considered the independent effects of specific physical

> activity components, only total sports or recreational activities (P:

> for trend=0.042) and vigorous activities (P: for trend=0.02) were

> inversely associated with the risk of CHD. These associations did not

> differ within subgroups of men defined by coronary risk factors.

> Finally, among men with multiple coronary risk factors, those

> expending >/=4,200 kJ/wk had reduced CHD risk compared with men

> expending <4,200 kJ/wk. CONCLUSIONS: Total physical activity and

> vigorous activities showed the strongest reductions in CHD risk.

> Moderate and light activities, which may be less precisely measured,

> showed nonsignificant inverse associations. The association between

> physical activity and a reduced risk of CHD also extends to men with

> multiple coronary risk factors.

> >

> >

> >

> > From McArdle Katch & Katch, EXERCISE PHYSIOLOGY: Energy,

> Nutrition and Human Performance

> >

> > " Research concerning the lifestyles and exercise habits or 17,000

> Harvard alumni, who enetered college between 1916 and 1950 gives

> strgon evidence that moderate aerobic exercise, equivalent to jogging

> about 3 miles a day, promotes good health and may actually add years

> to life. Regular exercise countered the life-shortening effects of

> cigarette smoking and excess body mass. Even for people with high

> BP, those who exercised regularly reduced their death rate by one -

> half. Genetic tendencies toward an early death were countered by

> regular exercise. ......... From the perspective of energy

> expenditure, the life expectancy of harvard alumni increased steadily

> from an energy expenditure of 500 kcal per week - 3500 kcal; this was

> equivalent to 6 to 8 hours of " strenuous " weekly exercise. In

> addition, active men lives an average of 1-2 years longer then

> sedentary classmates. Beyond weekly exercise of 3500 kcal, there

> were NO ADDITIONAL health of longevity benefits. When exercise was

> carried to extremes, the men had higher death rates than more

> moderately active colleagues.

[Guest guest]

> Here, it is the-more-the-better... in terms of risk of coronary

events:

> " Women in increasing quintiles of energy expenditure measured in

metabolic

> equivalents (the MET score) had age-adjusted relative risks of

coronary events of

> 1.00, 0.73, 0.69, 0.68, and 0.47 "

>

> Walking Compared with Vigorous Exercise for the Prevention of

Cardiovascular

> Events in Women

> JoAnn E. Manson et al

> http://content.nejm.org/cgi/content/abstract/347/10/716

> NEJM 2002

>

> --

>

> Ken

Hello,

How much exercise? Don't know. But for an upper bound for amount of

exercise it's around 490 calories/day. See,

" An evolutionary perspective on human physical activity: implications

for health. "

http://snipurl.com/9k0w

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=

Retrieve & db=pubmed & dopt=Abstract & list_uids=14527637

Or from message 15097,

" McArdle Katch & Katch, EXERCISE PHYSIOLOGY: Energy, Nutrition and

Human Performance "

" Beyond weekly exercise of 3500 kcal (editors note ---500

calories/day), there were NO ADDITIONAL health of longevity benefits.

When exercise was carried to extremes, the men had higher death rates

than more moderately active colleagues. "

So you should probably not train for too many marathons unless you can

do so on about 5 miles per day or 35 miles per week.

Aequalsz

[Guest guest]

Hi Freebird:

To answer your question: " ........... one also will

need sufficent strength, endurance and flexibility to do the things

one would like to do. Like take a five mile hike across the hills on

a beautiful spring morning if one feels in the mood. " Or, I might

have added, play a couple of rounds of golf, instead; or, sail his

Hobie across the lake in 30 mph winds; or whatever.

There is a fair amount of evidence that, from the HEALTH point of

view, diminishing returns set in pretty quick once you go above

the " walk from your bed to the bathroom, to the kitchen, to the

garage and back each day .......... " , as I have quoted here before

('The Exercise Myth' - Dr. Henry , cardiologist, Cornell

Medical Centre). And from the same source: " Fitness has absolutely

nothing to do with health " . Notice he used the word 'fitness'. He

did not say no exercise at all is fine. He said that being 'fit' is

not necessary to health. Jeff's link, on which I was commenting,

provided additional evidence that diminishing returns set in fairly

quickly. And even the benefits of substantial amounts of exercise

are only modest, even in a group (people in general) which, on the

average, we know has pretty poor nutrition.

So, what are your recommendations for exercise? Do they vary with

age? (Or would you recommend that 100-year olds take the same amount

of exercise as 30-year olds for instance?)

And do you believe those recommendations would also provide health

benefits to people who are established on CR with typical CR-type CVD

risk profiles? If you do, what evidence do you have that greater

than modest amounts of exercise produce additional benefits for

people who A) are in the range of ages of those who post here, and

have CR-type CVD risk data? That is ........... for people who,

unlike those in the study, are NOT in need of exercise to make a

minor partial (20%) correction of the problems precipitated by poor

nutrition?

(These are not rhetorical questions).

Rodney.

PS: You misquoted my post by leaving out the first word of the quote

and capitalizing the first letter of the second word to make it

appear as if it was the complete sentance. It wasn't.

>

> " Jogging one mile a week will do it " ..

>

> What do you think a one mile a week jog will accomplish?

>

> --- In , " Rodney " <perspect1111@y...>

wrote:

> >

> > Hi folks:

> >

> > What is interesting about the first study noted by Jeff below, is

> > that the apparent protective effect, even for those expending

more

> > than 12,600 kj/week on exercise, is only a reduction of 20%. And

> > that effect is apparently no greater than the benefit from 4,200 -

> > 8,400 kj/week.

> >

> > This seems to argue in favor of the view that the benefits of

> > exercise are modest, and that modest to moderate amounts of it

will

> > reap all the benefits that are to be had from exercise.

> >

> > But there is another possible issue that may be highly relevant

to us

> > here. What kind of lives did the subjects in this study lead,

> > besides their exercising? It is likely that they were much like

the

> > rest of the population - not entirely a healthy 'lifestyle'.

> > Although the fact that they took exercise suggests they may have

been

> > more health-conscious than average.

> >

> > So, perhaps the explanation for the demonstrated benefit of

exercise

> > shown in these studies is that it can reverse some (but not a

heck of

> > a lot, apparently) of the effects of poor nutrition. For

example, I

> > believe cholesterol levels are considerably reduced after

exercise,

> > as if it gets burnt off in the process of exercising.

> >

> > But what if your LDL is 50 before you even get around to thinking

> > about exercising? Will you see any CHD benefit from exercise? I

> > rather doubt it. But I assume that if there still is a benefit,

it

> > would be less than the 20% shown in the study. Do we know the

> > answer? Given the CHD risk profiles of people on CR, can we

> > reasonably expect to see further CHD benefit from exercise?

> >

> > Clearly, in old age, in addition to clean arteries, one also will

> > need sufficent strength, endurance and flexibility to do the

things

> > one would like to do. Like take a five mile hike across the

hills on

> > a beautiful spring morning if one feels in the mood. One will

not

> > acquire that capacity sitting in a chair watching TV. But how

much

> > exercise does one really need to get it? Hopefully jogging one

mile

> > once a week will do it ; ^ )))

> >

> > But I am interested in evidence indicating otherwise.

> >

> > Rodney.

[Guest guest]

How do you or Dr. Sol define " fit " ?

> > >

> > > Hi folks:

> > >

> > > What is interesting about the first study noted by Jeff below, is

> > > that the apparent protective effect, even for those expending

> more

> > > than 12,600 kj/week on exercise, is only a reduction of 20%. And

> > > that effect is apparently no greater than the benefit from 4,200 -

>

> > > 8,400 kj/week.

> > >

> > > This seems to argue in favor of the view that the benefits of

> > > exercise are modest, and that modest to moderate amounts of it

> will

> > > reap all the benefits that are to be had from exercise.

> > >

> > > But there is another possible issue that may be highly relevant

> to us

> > > here. What kind of lives did the subjects in this study lead,

> > > besides their exercising? It is likely that they were much like

> the

> > > rest of the population - not entirely a healthy 'lifestyle'.

> > > Although the fact that they took exercise suggests they may have

> been

> > > more health-conscious than average.

> > >

> > > So, perhaps the explanation for the demonstrated benefit of

> exercise

> > > shown in these studies is that it can reverse some (but not a

> heck of

> > > a lot, apparently) of the effects of poor nutrition. For

> example, I

> > > believe cholesterol levels are considerably reduced after

> exercise,

> > > as if it gets burnt off in the process of exercising.

> > >

> > > But what if your LDL is 50 before you even get around to thinking

> > > about exercising? Will you see any CHD benefit from exercise? I

> > > rather doubt it. But I assume that if there still is a benefit,

> it

> > > would be less than the 20% shown in the study. Do we know the

> > > answer? Given the CHD risk profiles of people on CR, can we

> > > reasonably expect to see further CHD benefit from exercise?

> > >

> > > Clearly, in old age, in addition to clean arteries, one also will

> > > need sufficent strength, endurance and flexibility to do the

> things

> > > one would like to do. Like take a five mile hike across the

> hills on

> > > a beautiful spring morning if one feels in the mood. One will

> not

> > > acquire that capacity sitting in a chair watching TV. But how

> much

> > > exercise does one really need to get it? Hopefully jogging one

> mile

> > > once a week will do it ; ^ )))

> > >

> > > But I am interested in evidence indicating otherwise.

> > >

> > > Rodney.

[Guest guest]

First of all, you're assuming that a favorable HDL precludes you from

developing IHD (I wouldn't assume this.)

Secondly, you glossed over Jeff's first two studies that show a

SIGNIFICANT relationship b/w exercise intensity/capacity and mortality!!

Thridly, I think it absurd that anyone (let alone a cadiologist) would

claim walking from your bedroom to the bathroom constitutes exercise,

sufficient or otherwise! ROFL!!

> > >

> > > Hi folks:

> > >

> > > What is interesting about the first study noted by Jeff below, is

> > > that the apparent protective effect, even for those expending

> more

> > > than 12,600 kj/week on exercise, is only a reduction of 20%. And

> > > that effect is apparently no greater than the benefit from 4,200 -

>

> > > 8,400 kj/week.

> > >

> > > This seems to argue in favor of the view that the benefits of

> > > exercise are modest, and that modest to moderate amounts of it

> will

> > > reap all the benefits that are to be had from exercise.

> > >

> > > But there is another possible issue that may be highly relevant

> to us

> > > here. What kind of lives did the subjects in this study lead,

> > > besides their exercising? It is likely that they were much like

> the

> > > rest of the population - not entirely a healthy 'lifestyle'.

> > > Although the fact that they took exercise suggests they may have

> been

> > > more health-conscious than average.

> > >

> > > So, perhaps the explanation for the demonstrated benefit of

> exercise

> > > shown in these studies is that it can reverse some (but not a

> heck of

> > > a lot, apparently) of the effects of poor nutrition. For

> example, I

> > > believe cholesterol levels are considerably reduced after

> exercise,

> > > as if it gets burnt off in the process of exercising.

> > >

> > > But what if your LDL is 50 before you even get around to thinking

> > > about exercising? Will you see any CHD benefit from exercise? I

> > > rather doubt it. But I assume that if there still is a benefit,

> it

> > > would be less than the 20% shown in the study. Do we know the

> > > answer? Given the CHD risk profiles of people on CR, can we

> > > reasonably expect to see further CHD benefit from exercise?

> > >

> > > Clearly, in old age, in addition to clean arteries, one also will

> > > need sufficent strength, endurance and flexibility to do the

> things

> > > one would like to do. Like take a five mile hike across the

> hills on

> > > a beautiful spring morning if one feels in the mood. One will

> not

> > > acquire that capacity sitting in a chair watching TV. But how

> much

> > > exercise does one really need to get it? Hopefully jogging one

> mile

> > > once a week will do it ; ^ )))

> > >

> > > But I am interested in evidence indicating otherwise.

> > >

> > > Rodney.

[Guest guest]

Regarding the second point i should clarify: a significant INVERSE

relationship ;-D

> > > >

> > > > Hi folks:

> > > >

> > > > What is interesting about the first study noted by Jeff below, is

> > > > that the apparent protective effect, even for those expending

> > more

> > > > than 12,600 kj/week on exercise, is only a reduction of 20%. And

> > > > that effect is apparently no greater than the benefit from 4,200 -

> >

> > > > 8,400 kj/week.

> > > >

> > > > This seems to argue in favor of the view that the benefits of

> > > > exercise are modest, and that modest to moderate amounts of it

> > will

> > > > reap all the benefits that are to be had from exercise.

> > > >

> > > > But there is another possible issue that may be highly relevant

> > to us

> > > > here. What kind of lives did the subjects in this study lead,

> > > > besides their exercising? It is likely that they were much like

> > the

> > > > rest of the population - not entirely a healthy 'lifestyle'.

> > > > Although the fact that they took exercise suggests they may have

> > been

> > > > more health-conscious than average.

> > > >

> > > > So, perhaps the explanation for the demonstrated benefit of

> > exercise

> > > > shown in these studies is that it can reverse some (but not a

> > heck of

> > > > a lot, apparently) of the effects of poor nutrition. For

> > example, I

> > > > believe cholesterol levels are considerably reduced after

> > exercise,

> > > > as if it gets burnt off in the process of exercising.

> > > >

> > > > But what if your LDL is 50 before you even get around to thinking

> > > > about exercising? Will you see any CHD benefit from exercise? I

> > > > rather doubt it. But I assume that if there still is a benefit,

> > it

> > > > would be less than the 20% shown in the study. Do we know the

> > > > answer? Given the CHD risk profiles of people on CR, can we

> > > > reasonably expect to see further CHD benefit from exercise?

> > > >

> > > > Clearly, in old age, in addition to clean arteries, one also will

> > > > need sufficent strength, endurance and flexibility to do the

> > things

> > > > one would like to do. Like take a five mile hike across the

> > hills on

> > > > a beautiful spring morning if one feels in the mood. One will

> > not

> > > > acquire that capacity sitting in a chair watching TV. But how

> > much

> > > > exercise does one really need to get it? Hopefully jogging one

> > mile

> > > > once a week will do it ; ^ )))

> > > >

> > > > But I am interested in evidence indicating otherwise.

> > > >

> > > > Rodney.

[Guest guest]

From my personal view...

I point I made earlier is that some of this is " semantics " and how we

define acitivity, exercise and fitness. MET levels is one way as is

caloric expenditure and now we have total steps. METs tells intensity

but not total output, while caloric expenditure tells total output but

not intensity and total steps estimates output. And we have problems

in the way it is measured and/or collected.

The other point I tried to make is that there seems to be some level of

activity, including endurance, strength and range of motion (which I

think is more important than flexibility) that we need to have to

survive. Granted our modern day society has made it so we don't need

those as much to survive and can even get by without them.

I think both of the above add to the confusion in the data and the

apparent conflicts.

My own PERSONAL interpretation (and this is stictly personal) of all I

have read and discussed... (which could be individualized to anyone else

personal lifestyle) is we get the most benefit (without the

consequences of overdoing it) by

- the " equivalent " of a 30-60 minutes brisk walk a week (brisk means

walking as if you had somewhere to go and were running late)

- the equivalent of 2-3 strength training sessions a week of around

15-30 minutes

- the equivalent of some brief but very high intensity endurance

sessions (ie 5-10 fast sprints of 10-15 seconds each 1-3x a week)

- 5-15 minutes of ROM exercises daily if possible, which are basically

just simple calisthenics in which you move all your body parts through

their full Range-Of-Motion a few times each. Doing this will prevent

the loss of flexibility as we age.

All of this can be accomplished in 60 minutes or less a day.

If you get all this in the course of your normal life, than you don't

need to add in.

If you get some of it but not others, just formally add in the parts you

are missing.

Except for the brief sprints, none of this is strenous, most of it can

be fun, and can be fit in simply. And the brief sprints, are actually

invigorating as they are intense, but brief and not done often, so not

draining.

And I say " equivalent " cause for endurance, it can be walking, biking or

whatever. For strength it could be weights, machines, dumbells, body

weight exercises etc, Whatever you prefer.

[Guest guest]

Hi Freebird:

I guess you should take up this argument with Dr. . Or read

his book. Perhaps he knows something you don't. He is a

cardiologist.

But probably more important, all these studies relate to CVD which,

based in the CVD risk factors of people on CR, is unlikely to be a

huge problem for us.

I have searched elsewhere for evidence that lots of exercise helps

protect against other illnesses. For osteoporosis it definitely does

help. For cancer and immunity the studies are conflicting. Some

show a small improvement in immunity with exercise, others do not.

There is a much greater increase in immunity from drinking tea

according to a study posted here about six months ago.

I have also checked the New England Centenarian study website. They

mention eight common factors of the subjects in their study.

Exercise is not on the list.

So what do you believe an older person on CR (say fifty or more)

should do in the way of exercise, and what is the reason for that

belief?

Rodney.

> > > > >

> > > > > Hi folks:

> > > > >

> > > > > What is interesting about the first study noted by Jeff

below, is

> > > > > that the apparent protective effect, even for those

expending

> > > more

> > > > > than 12,600 kj/week on exercise, is only a reduction of

20%. And

> > > > > that effect is apparently no greater than the benefit from

4,200 -

> > >

> > > > > 8,400 kj/week.

> > > > >

> > > > > This seems to argue in favor of the view that the benefits

of

> > > > > exercise are modest, and that modest to moderate amounts of

it

> > > will

> > > > > reap all the benefits that are to be had from exercise.

> > > > >

> > > > > But there is another possible issue that may be highly

relevant

> > > to us

> > > > > here. What kind of lives did the subjects in this study

lead,

> > > > > besides their exercising? It is likely that they were much

like

> > > the

> > > > > rest of the population - not entirely a

healthy 'lifestyle'.

> > > > > Although the fact that they took exercise suggests they may

have

> > > been

> > > > > more health-conscious than average.

> > > > >

> > > > > So, perhaps the explanation for the demonstrated benefit of

> > > exercise

> > > > > shown in these studies is that it can reverse some (but not

a

> > > heck of

> > > > > a lot, apparently) of the effects of poor nutrition. For

> > > example, I

> > > > > believe cholesterol levels are considerably reduced after

> > > exercise,

> > > > > as if it gets burnt off in the process of exercising.

> > > > >

> > > > > But what if your LDL is 50 before you even get around to

thinking

> > > > > about exercising? Will you see any CHD benefit from

exercise? I

> > > > > rather doubt it. But I assume that if there still is a

benefit,

> > > it

> > > > > would be less than the 20% shown in the study. Do we know

the

> > > > > answer? Given the CHD risk profiles of people on CR, can

we

> > > > > reasonably expect to see further CHD benefit from exercise?

> > > > >

> > > > > Clearly, in old age, in addition to clean arteries, one

also will

> > > > > need sufficent strength, endurance and flexibility to do

the

> > > things

> > > > > one would like to do. Like take a five mile hike across

the

> > > hills on

> > > > > a beautiful spring morning if one feels in the mood. One

will

> > > not

> > > > > acquire that capacity sitting in a chair watching TV. But

how

> > > much

> > > > > exercise does one really need to get it? Hopefully jogging

one

> > > mile

> > > > > once a week will do it ; ^ )))

> > > > >

> > > > > But I am interested in evidence indicating otherwise.

> > > > >

> > > > > Rodney.

[Guest guest]

Thanks, Jeff, I had not thought of sprints of 10 - 15 secs. I can probably do that. (It may look a lot like jogging to start).

----- Original Message -----

From: Jeff Novick

Sent: Tuesday, October 05, 2004 3:02 PM

Subject: RE: [ ] Re: what constitutes enough exercise?

From my personal view...I point I made earlier is that some of this is "semantics" and how wedefine acitivity, exercise and fitness. MET levels is one way as iscaloric expenditure and now we have total steps. METs tells intensitybut not total output, while caloric expenditure tells total output butnot intensity and total steps estimates output. And we have problemsin the way it is measured and/or collected.The other point I tried to make is that there seems to be some level ofactivity, including endurance, strength and range of motion (which Ithink is more important than flexibility) that we need to have tosurvive. Granted our modern day society has made it so we don't needthose as much to survive and can even get by without them. I think both of the above add to the confusion in the data and theapparent conflicts.My own PERSONAL interpretation (and this is stictly personal) of all Ihave read and discussed... (which could be individualized to anyone elsepersonal lifestyle) is we get the most benefit (without theconsequences of overdoing it) by- the "equivalent" of a 30-60 minutes brisk walk a week (brisk meanswalking as if you had somewhere to go and were running late) - the equivalent of 2-3 strength training sessions a week of around15-30 minutes- the equivalent of some brief but very high intensity endurancesessions (ie 5-10 fast sprints of 10-15 seconds each 1-3x a week) - 5-15 minutes of ROM exercises daily if possible, which are basicallyjust simple calisthenics in which you move all your body parts throughtheir full Range-Of-Motion a few times each. Doing this will preventthe loss of flexibility as we age.All of this can be accomplished in 60 minutes or less a day.If you get all this in the course of your normal life, than you don'tneed to add in.If you get some of it but not others, just formally add in the parts youare missing. Except for the brief sprints, none of this is strenous, most of it canbe fun, and can be fit in simply. And the brief sprints, are actuallyinvigorating as they are intense, but brief and not done often, so notdraining. And I say "equivalent" cause for endurance, it can be walking, biking orwhatever. For strength it could be weights, machines, dumbells, bodyweight exercises etc, Whatever you prefer.

[Guest guest]

>> Thanks, Jeff, I had not thought of sprints of 10 - 15 secs. I can probably do that. (It may look a lot like jogging to start).

The energy system we use during short intense sprints is seperate from the two common energy systems , aerobic and anerobic. It's the P-Cr (Phospho-creatine) system (ita also been given other names) which we only have enough to last about 10-15 seconds. Past that, you go into anerobic. P-Cr wil regenerate itself rather quickly, although you may not.

Its also why you can sprint "all out" for more than that brief period. Peak sprint time can only be maintained for a short burst. If you interested I can send you some articles/data on the proposed benefit in this but I am not sure it relates exactly to CR-ON but more to overall fitness and QOL. Shorter more intense sprints improve overall fitness levels better than longer less intense ones. It doesnt take alot to make a difference. Mix it in with some walking and you have the best of both worlds without hurting yourself or having to work out hard for long periods.

My personal pattern is that I like to do them on my Schwinn Air-Dyne. After about -15 minutes at a moderate pace, I will do a 10-15 second intense sprint, than go back to moderate for the rest of the minute, about 45-50 seconds, than repeat 5-10x or whatever feels right that day. Than finish off the half hour at a moderate pace even though I dont know what "moderate" means . Do fewer of them and rest more if you need in the beginning because you dont want to hurt or strain yourself. Also, if you are doing this on the street or road, watch out for trash, loose rocks, gravel, etc. Its easy to trip.

You can read an lay article I contributed to about this very topic and there is a citation in it of one of my favorites studies on this whole concept.

http://www.cbass.com/EACAPING.HTM

[Guest guest]

this might be of some small interest to anyone following the portion of this thread on interval training. (I post it because it's brand new.)

Int J Sports Med. 2004 Oct;25(7):509-15. Related Articles, Links

 

Fatigue and Recovery After High-Intensity Exercise Part II: Recovery Interventions.

"These results show that the recovery... after an intermittent high-intensity uphill running exercise do not depend on [either doing nothing, running slowly, or using electrostimulation]

PMID: 15459831

--

Ken

[Guest guest]

In a message dated 10/5/04 8:24:22 AM Eastern Daylight Time, perspect1111@... writes:

What is interesting about the first study noted by Jeff below, is

that the apparent protective effect... is only a reduction of 20%.

This seems to argue in favor of the view that the benefits of

exercise are modest

regarding the use of the term "modest": that depends on whether they are using risk ratio or odds ratio. Please see my post, with Subject: changed to STATS.

So, an odds ratio of .8 might equate to a risk ratio of .5, e.g.

And, to confuse things even more, the use of the term "risk ratio" might now be a catchall phrase, and be used even when it is really an odds ratio. At this point, it seems to me that mention of 'multivariate' or 'logistic regression' means it is an odds, not a risk, ratio.

--

Ken

[Guest guest]

oops, correction and additional comment..

>>Its also why you can sprint " all out " for more than that brief period.

I meant " can't " sprint....

If you do the estimated calculations on the amount of exercise I mentioned, on

the low end, its about 1200-1500 calories per week, and at the high end about

2500-3000. At 6 days per week thats 200 -500 per day. Both of those are

clearly within any data that has shown benefit and not over and data that has

shown to be too much. (Intensity will be individualized and will only move

estimates to the higher end but still within reason).

Also, those numbers are clearly within the range that anyone could achieve

" naturally " within the context of an " active " lifestyle without formally

engaging in " exercise "

[Guest guest]

Good stuff Ken, thank you.

So when a study says: " Compared with men expending <2,100 kJ/wk, men

expending 2,100 to 4,199, 4,200 to 8,399, 8,400 to 12,599, and

>/=12,600 kJ/wk had multivariate relative risks of 0.90, 0.81, 0.80,

and 0.81, respectively " , what does it mean?

Does the 0.80 number mean that the risk of an event for that group

relative to the base group (in this case the '<2,100kJ/wk' group) was

20% less? Or does it mean something else? Surely those numbers do

not signify the risk in each group compared with the people who had

no events (or compared with a group all members of which had an

event)?

Before I read your post I hadn't realized I had been confused. Now,

after reading it, I am more confused than ever ;; ^ )))

Rodney.

> In a message dated 10/5/04 8:24:22 AM Eastern Daylight Time,

> perspect1111@y... writes:

>

> > What is interesting about the first study noted by Jeff below, is

> > that the apparent protective effect... is only a reduction of

20%.

> >

> > This seems to argue in favor of the view that the benefits of

> > exercise are modest

>

> regarding the use of the term " modest " : that depends on whether

they are

> using risk ratio or odds ratio. Please see my post, with Subject:

changed to

> STATS.

>

> So, an odds ratio of .8 might equate to a risk ratio of .5, e.g.

>

> And, to confuse things even more, the use of the term " risk ratio "

might now

> be a catchall phrase, and be used even when it is really an odds

ratio. At

> this point, it seems to me that mention of 'multivariate'

or 'logistic

> regression' means it is an odds, not a risk, ratio.

>

> --

>

> Ken

[Guest guest]

Well Ken:

Tell us what the 'odds ratio' means in this study (please):

" Effects of green tea intake on the development of coronary artery

disease.

Sano J, Inami S, Seimiya K, Ohba T, Sakai S, Takano T, Mizuno K.

Department of Medicine, Chiba Hokusoh Hospital, Nippon Medical

School, Chiba, Japan. sano-123@...

BACKGROUND: Green tea, a popular beverage in Japan, contains many

polyphenolic antioxidants, which might prevent atherosclerosis. This

study was designed to determine whether the consumption of green tea

is proportionately associated with a decreased incidence of coronary

artery disease (CAD) and the cardiovascular and cerebrovascular

prognosis. METHODS AND RESULTS: The study group comprised 203

patients who underwent coronary angiography (109 patients with

significant coronary stenosis and 94 patients without). Predictors

for CAD were analyzed and the patients' cardiovascular and

cerebrovascular events were followed. Green tea consumption was

significantly higher in patients without CAD than in those with CAD

(5.9+/-0.5 vs 3.5+/-0.3 cups/day; p<0.001). An inverse relationship

between the intake of green tea and the incidence of CAD was observed

(p<0.001). The green tea intake per day was an independent predictor

for CAD based on a multivariate logistic regression analysis (odds

ratio: 0.84 and 95% confidence interval: 0.76-0.91). In contrast, the

green tea intake was not a predictor of cardiovascular and

cerebrovascular events based on the proportional hazard model.

CONCLUSIONS: Green tea consumption was associated with a lower

incidence of CAD in the present study population in Japan. Therefore,

the more green tea patients consume, the less likely they are to have

CAD. "

I am glad you raised the issue of this terminology, Ken. It is

something that it would be good to understand clearly.

Rodney.

> In a message dated 10/5/04 8:24:22 AM Eastern Daylight Time,

> perspect1111@y... writes:

>

> > What is interesting about the first study noted by Jeff below, is

> > that the apparent protective effect... is only a reduction of

20%.

> >

> > This seems to argue in favor of the view that the benefits of

> > exercise are modest

>

> regarding the use of the term " modest " : that depends on whether

they are

> using risk ratio or odds ratio. Please see my post, with Subject:

changed to

> STATS.

>

> So, an odds ratio of .8 might equate to a risk ratio of .5, e.g.

>

> And, to confuse things even more, the use of the term " risk ratio "

might now

> be a catchall phrase, and be used even when it is really an odds

ratio. At

> this point, it seems to me that mention of 'multivariate'

or 'logistic

> regression' means it is an odds, not a risk, ratio.

>

> --

>

> Ken

[Guest guest]

>>Tell us what the 'odds ratio' means in this study (please):

Its simple....

The " ODDS " are that the " RISK " for dying young is " RELATIVE " to how I live my

life.

[Guest guest]

In a message dated 10/6/04 10:06:49 PM Eastern Daylight Time, perspect1111@... writes:

Well Ken:

Tell us what the 'odds ratio' means in this study (please):

"Effects of green tea intake on the development of coronary artery

disease.The green tea intake per day was an independent predictor

for CAD based on a multivariate logistic regression analysis (odds

ratio: 0.84 and 95% confidence interval: 0.76-0.91). In contrast, the

green tea intake was not a predictor of cardiovascular and

cerebrovascular events based on the proportional hazard model.

Rodney, I only know (so far) what i've read since noticing in an abstract that the figures for "risk ratio" (aka "relative risk") were different than the figures for an odds ratio. So, not being an expert on this, here's my view: you can't know the risk ratio from the abstract, since the abstract gives an odds ratio. But if the risk ratio were .84, then yes, that means a person drinking the tea has only 84% predicted chance of getting CAD as the non-tea-drinker. (...but having an actual vascular event is not related to ho w much green tea you drink.)

Judging from the chart on http://jama.ama-assn.org/cgi/reprint/280/19/1690.pdf

the risk ratio might actually be higher than .84, depending on the incidence of CAD in the study group: with greater and greater incidence of the effect (i.e., more have CAD), the spread between risk and odds ratios becomes greater and graeter. This wold have been nore clear, I think, if the logic in the chart was not inverted.)

Also, we probably can't always know when an actual risk ratio is being given, because researchers often seem to be calling everything a risk ratio, even when it's not. So, I agree with you that it is quite important, since you can't make a judgment relating to the absolute size of an effect unless you have an actual risk ratio figure.

BUT, I'd suppose this chart means that the risk ratio cannot be a lower figure than the odds ratio. And that is in direct confliuct with actual numbers shown in the study at:

http://content.nejm.org/cgi/content/abstract/347/10/716

...unless the numbers reported for "relative risks" there are really odds ratios. So, it seems to go round and round.

Btw, IIRC, you can't get a risk ratio in a case-control study.

And also btw: the other part from your abstract which says: "95% confidence interval: 0.76-0.91"

means that we can be 95% sure that the actual odds ratio lies somewhere between .76 and .91. I'd guess this relates to the number of subjects and to the size of the observed effect. Some of these intervals are much larger.

--

Ken

[Guest guest]

In a message dated 10/5/04 4:57:45 PM Eastern Daylight Time, perspect1111@... writes:

I guess you should take up this argument with Dr. . Or read

his book. Perhaps he knows something you don't. He is a

cardiologist.

yes, but I'd bet you can find a book written by MDs, PhDs, or whomever, that says just about anything. I recall one that claimed that hGH is not related to PCa. It was written by an anti-aging MD, and he used for evidence reports from a practice that was selling (oops, I mean prescribing) lots of recombinant (synthetic) hGH injections to their patients.

Doctors are not immune from expressing their own prejudices, having to do with their source of income, status, politics or whatever.

--

Ken

[Guest guest]

Hi Ken:

After reading that I am now glad I had said " perhaps " !

Rodney.

> In a message dated 10/5/04 4:57:45 PM Eastern Daylight Time,

> perspect1111@y... writes:

>

> > I guess you should take up this argument with Dr. . Or

read

> > his book. Perhaps he knows something you don't. He is a

> > cardiologist.

>

> yes, but I'd bet you can find a book written by MDs, PhDs, or

whomever, that

> says just about anything. I recall one that claimed that hGH is not

related to

> PCa. It was written by an anti-aging MD, and he used for evidence

reports

> from a practice that was selling (oops, I mean prescribing) lots of

recombinant

> (synthetic) hGH injections to their patients.

>

> Doctors are not immune from expressing their own prejudices, having

to do

> with their source of income, status, politics or whatever.

>

> --

>

> Ken

[Guest guest]

> Here, it is the-more-the-better... in terms of risk of coronary

events:

> " Women in increasing quintiles of energy expenditure measured in

metabolic

> equivalents (the MET score) had age-adjusted relative risks of

coronary events of

> 1.00, 0.73, 0.69, 0.68, and 0.47 "

>

> Walking Compared with Vigorous Exercise for the Prevention of

Cardiovascular

> Events in Women

> JoAnn E. Manson et al

> http://content.nejm.org/cgi/content/abstract/347/10/716

> NEJM 2002

>

> --

>

> Ken

Dont neglect the mood aspect, happiness definitely can add to

health. If running 4 times a week makes you miserable then it might

be good to find another alternative. However if sitting on the

couch 24/7 makes you happy, you might should consider doing some

exercise anyway:)

[Guest guest]

In a message dated 10/13/04 2:51:56 AM Eastern Daylight Time, edwin_boyette@... writes:

Dont neglect the mood aspect, happiness definitely can add to

health.

I couldn't agree with you more, Edwin. Besides, it's innately enjoyable for me. If I heard that the world would end in a week, I'd be sure to spend some of that time lifting weights, maybe doing some sprints, too.

Intense exercise, especially, makes me *feel* good. I don't believe that's limited to or even necessarily caused by endorphins. Tv doctor Bob Arnot was once stumping fo r his anti-aging book several years ago, and even he proposed that exercise that is fun (like mountain biking) will stimulate your system in beneficial ways that a treadmill or exercise bike won't. I'm also struck that hormones (like adrenaline) are also neuro-transmitters (usually then referred to as epinephrine). So the connection works both ways.

--

Ken