My personal experience here suggests a some thoughts. 1) intense exercise
is more likely to induce additional drive to eat. 2) moderate exercise
doesn't increase appetite and may lower it. 3) Extended duration exercise
ramps appetite unless the intensity is held under a certain level.4) Certain
kinds of extended exercise might contain periods of highly intense activity
and low intensity activity. 5) The more high intensiy exercise present, the
greater the desire to compensate via overeating. Even if the intensity is
low, if done long enough, it will ramp appetite.

I think what is intense depends on the person. Achieving 90% or more of max
heart rate is intense.

I think that for weight loss, one can use high intensity exercise, but one
much be careful not to do too much, Again, that depends on the person. Over
time, one can work up a curve so that more intense exercise can be done
without a response to compensate by eating. I think high intensity exercise
is more protective of the heart than low intensity, assuming of course that
one survives the HI exercise.

It is possible for two people who weigh the same to have very different
ability and background for exercise, and thus have completely different
responses to a 500-kcal session of exercise. Furthermore, there is a huge
difference in 500-kcals burned over and hour vs 30 minutes. Looking only at
work done without paying attention to power output is not going to make for
a good study, IMO.

"Jim" wrote in message
...
SUMMARY

Results vary in 12 week supervised exercise induced weight loss trials
with 35 obese and overweight subjects. "Compensatory Responses", including
eating more (working up an appetite?) were observed as some of the reason
for individual variations in weight loss response.

Reminds me of Mr. Banning's 1862 comments about exercise not reducing
weight but givng rise to a healthy appetite.

================================================== ==============
http://www.sciencedaily.com/releases...1101092802.htm

Weight Loss: Not One Size Fits All

ScienceDaily (Nov. 7, 2007) — There is no "one size fits all" when it
comes to weight loss through exercise, says Queensland University of
Technology behavioural scientist Neil King.

Dr Neil King, from QUT's Institute of Health and Biomedical Innovation, is
the lead author of a study conducted in collaboration with the University
of Leeds in the UK, which has been published recently in the International
Journal of Obesity.

"When it comes to losing weight, a lot of people assume if you lose less
than the predicted weight then you aren't exercising enough, and that is
why you aren't getting the desired results," Dr King said.

"This study is the first evidence-based study that shows despite people
doing the same amount of supervised exercise people lose different amounts
of weight."

The study, which focused on 35 overweight and obese people from the UK,
sought to identify and characterise the variability in exercise-induced
weight loss.

Participants undertook a 12-week supervised exercise program that was
individually tailored to expend 500 calories per session. During this time
their weight loss and behavioural outcomes were monitored.

Dr King said the study found the role of exercise as an effective weight
management method could be undermined by "compensatory responses" such as
a person's increased hunger and food intake as a result of their increased
energy expenditure.

"People, who we refer to as compensators, are those who compensate for the
increase in exercise-induced energy expenditure, by adjusting their food
intake" he said.

"For some people this might be in responses to an automatic biological
drive, whereas for others it might be a deliberate reward-based increase."

Dr King said what this study showed was that some individuals were
predisposed to compensatory responses, rendering them resistant to the
theoretical weight loss benefits of exercise.

"The individual variability here demonstrates the need to treat people as
individuals," he said.

"It also highlights the importance of determining the mechanisms that may
explain this variability, such as how to treat the more resistant
compensatory person to improve their weight management outcomes.

"Those resistant to exercise might be better suited to weight management
strategies which include controlled dietary intake, in addition to
exercise."

Dr King said the novelty and therefore the strength of this study, was
that the exercise was supervised.

"Therefore, unlike unsupervised exercise interventions, any variability in
weight loss cannot be explained by differences in exercise compliance," he
said.

Adapted from materials provided by Queensland University of Technology.