Not sure I understand this study, then again I might just be odd in general so since I only have myself to compair things with that might be where i'm not understanding things.

My RHR is 53, I will hit the weight room for just over 60 minutes and get my HR into the 130s range (harder to get it higher, I can for higher weights, but that doesn't last long till my body gets use to the new weight). Anyhow, after that i'll hit the elliptical for a solid 65 minutes (no resting at all) and get my HR between 150 and 160 and keep it there for about 45 of the 65 minues. Now cooling down my rate will go from that range to 110 in the 5 min cool down period and once i stop the elliptical its back down to 85 aveage (walking around average for me)

I don't understand how breaking something up if ones heart rate goes back down in a short amout of time (within norm I am told) how that will help with weight loss or maintance for that matter.

We need to be careful not to confuse an association with cause and effect. It is more likely that a break between intervals allowed the participants to work harder. Higher intensity exercise = more calories burned. How did they measure fat loss anyway? A studies conclusions are only as accurate as it's testing tools.

- I fail to see the direct correlation between heart rate and calories burned. A person with a resting HR of 100 is not burning more calories than a person with a resting HR of 50. And what if I down 800mg of caffeine pills. Now I am at a "fat burning" HR. But I'm sitting on my butt. Am I burning calories? No. An elevated HR void of muscular work is meaningless with regards to energy expenditure.

Bruce H:

Your metabolism has changed for one reason. Muscle tissue loss. After age 25 humans lose ~0.5 lb of muscle per year, unless a stimulus is in place to maintain it. www.sarcopenia.com Muscle tissue contributes to about 23% of your overall metabolism and is the only part that you have control over.

What can you do about this? Strength Training.

Have there been any similar tests on 50 year olds? My metabolism has changed, so I am interested what would work best for me. At 20 I was not too worried about which style of exercise burns more fat.

I do 6-10K steady runs during the week but often sneak in a walk break or two with the 10K. I always do my long runs with walk breaks. That's the only way I could have gone from non-runner to marathon training. And I'm quite sure it's the only way I'll be able to run a marathon - period. I've heard that you can increase your race time by up to ten minutes by adding walk breaks. Makes sense given how much longer my steady runs are when I don't get stuck at a red traffic light (sneaky walk breaks I call them). I also use the walk break to stretch a little.

Seems to me that athletic success is all about balance. Knowing when you can go all out and knowing when to pull it back or even take a break (i.e., when that old injury starts flaring up).

it is interesting , that it always takes a "research group " to come up with something we know since a long time by simply measuring the metabolic rate of each person exercising.
The reason of the above result is given by the fact , that after any workout you may stop physically moving , but your physiological apparatus does not stop immediatly , but has, depending on the intensity of the workout a ( so called hidden stress - see FaCT- canada )
What is a hidden stress.
Well you bike 20 km and you see that on your kilometer counter on the bike, You stop your workout, but that is only tru for your bike , you body still keeps burning higher amounts of calories , than if you would have done no bike ride.
So you add up 60 min workout plus 20 min as an example "hidden workout"
= 80 min calorie burns

30 min workout plsu 20 min "hidden stress"
+ 30 min workout + 20 min "hiiden stress" = 100 min workout.
The key is to verufy what the hidden stress realy is doing ( time wise , energy source wise and. so . on )
After that we can see the different ideas of interruotions in different work outs.
Golf is a very interesting activity with walk and stop as an ( interval activity ) and interestingly enough more glucose burn than fat burn , ) Important to know for people with juvenile diabetic and risk of hypoglycamia. )
have fun to think this ideas through

Once again researchers manage to prove the blindingly obvious. If your heart rate stays elevated for 15 minutes post-exercise then there will be greater calorie burn with the exercise in two 30 min segments (90 mins elevated heart rate) than one 60 minute segment (75 mins elevated heart rate) - assuming that the same heart rate is reached in each segment. However, if your aim is to increase endurance rather than burn fat, then a single exercise period is surely better.

An hour sounds like a lot, but if you go to the gym and warm up, hit the weights/machines for half an hour, then stair climb/run/skip for another half hour, it doesn't feel all that long.

And if you're short on time, go with a high-intensity workout instead. Circuit training, or an intense 30 min cardio workout can provide you with all of the same benefits of a longer but more moderate workout.

Usually, exercising is easy. The toughest part is getting off the couch.

I couldn't agree more with the findings in these reports. However, if moderate aerobic exercise is not coupled with, anaerobic (strength training), a healthy diet (5 or 6 smaller meals per day)and adequate sleep, then only part of the big picture is being addressed. If you add it all up, it amounts to a change in lifestyle. This I am sure is what creates the greatest difficulty for anyone who aspires to a higher level of health.