What is the real deal with the rate of burning calories? Im quite a portly fellow and am trying to lose some weight, but have a few questions about it i wouldnt mind having answered!
If i run for 40 minutes, will i burn twice the calories as if i run for 20mins (ie is it a linear relationship?)
Which is better, time spent exercising or distance travelled? for example if i run at 6mph for half an hour and 8mph for half an hour, is that the same as running at 7mph for an hour?
Also if im in a rush, can i cram my 3mile run in half an hour, compared to if ive got a free evening and can take twice as long to go the same distance?
Any other info/discussions are wholey welcome, please help this fat b*stard fight the tub!!!
If you’re really looking to cut weight I’d recommend using a high intensity interval training (HIIT) type plan. Basically you cycle your level of effort over the course of the cardio workout so essentially you run for a bit, then jog/walk for a bit, then run some more. Continue for the duration of your workout.
I’m in good shape, but cycling 20s sprints with 20s jog will knock me on my ass after just a few minutes. I don’t have a cite handy right now, but there is a good deal of legitimate research to backup this technique. You end up not burning quite as much during the actual workout, but it creates an elevation in metabolism that results in higher net caloric cost than regular low/moderate level cardio for the same workout duration.
interesting. (and exactly the type of answer i was after!)
I know this is going to be an impossible question to answer, but ill ask it anyway - your opinion rather than scientific fact would suffice! What is the relationship between your HIIT training compared to my current training? For example is 1/2 hour jogging equivalent to 20minutes of sprint/slow/sprint/slow?
Im just interested to know because fitness is unfortunately bottom of my priority list, and so if i can get away with working harder for 20minutes rather than a gentle 30mins then i would opt for that everytime! I have heard somewhere that duration is the overriding winner when it comes to losing weight.
My non-scientific opinion would be that 20 min of true HIIT would be more beneficial than 30 min of low intensity. However, one important aspect of HIIT is that the sprint portions MUST truly be high intensity. Some folks call for balls to the wall, all out sprinting which will tire you out well before you hit the 20 min mark. Others don’t take it quite to that extreme, but still keep it intense enough that the “sprint” portions are still a struggle to finish, especially toward the end of the workout.
Is the sprint section in speed or duration? because my treadmill will only go to 8mph which isnt exactly a sprint… although is hard to do for more than a few mins.
I believe that the number of calories burned depends on your heart rate. So the more you exert yourself, the more calories you burn. If you do a search for “calories burn heart rate”, you’ll get lots of hits.
When researching this a few years ago, this is what I found -
Exercise hard enough to get your heartrate high enough that the heart was working fairly hard, but not enough that you were straining or getting short of breath.
You needed to do this for at least 40-45 minutes to get any lasting benefit from it.
This would kick your metabolism up enough, that when you stopped, your metabolism would still remain high for several hours afterwards. A few minutes of hard exercise would get your rate up, but your metabolism would fall quickly also.
This was recommended for someone would was not in good shape, but wanted to get in better shape and burn calories.
Does this sound about right to those of you who have used an exercise program for weight loss?
Keep in mind, for weight loss you will build a calorie deficit (and lose weight) far more quickly and efficiently from calorie restriction than you will from exercise.
Exercise has lots of wonderful health benefits and I would never dissuade you from it. But in terms of weight loss, “burning” calories through physical exertion is far more effort than simply not taking in the calories in the first place.
Consider - Let’s say you’re pretty good, you exercise 5 / week. Each session you burn 500 calories (estimate from WebMD for a 200 lb man, 40 minutes of jogging at 11.5 minutes / mile)
Over the course of the week you’ve burned 2500 extra calories, with the caveat that your diet hasn’t changed and you aren’t eating more to compensate for the exercise. Not bad. 3 hours, 20 minutes of exercise over the week.
But you would have gotten the exact same energetic effect by simply restricting your diet by about 350 calories a day for the week. One bagel or one less slice of pizza per day. Easy, easy, easy.
IMO, the real way to look at it is: Calorie restriction makes you lose weight. Exercise improves your health. Exercise is great and important, but it’s the inefficient way to lose weight. Moderate calorie restriction is the quickest way to drop body fat.
… all of which assumes that your metabolism remains the same whether you are on a diet or not, and whether you are fit or not. None of which I understand to be true. Perhaps GameHat, you should give us some cites, this being GQ and all.
The four studies you cite discuss caloric intakes of 800-1200 kcal / day, 1194 kcal/day, 900-1100 kcal / day and 800 kcal / day. This is fairly severe calorie restriction, and signifcantly more than the example I gave of cutting 350 kcal a day (assuming adult male who needs maybe 2000 kcal / day to maintain weight).
The studies you linked aren’t all in agreement. From the Kraemer WJ, Volek JS, Clark KL et al study.
Which does not support the hypothesis of dieting -> metabolic loss. Granted, I think two of the other studies did find a drop in resting metabolic rate of something like 10%-15%, but none of them extended the study past the severe calorie restriction phase to see what happened after the subject resumed a normal diet.
Even if we grant that under a severely restricted calorie diet depresses the resting metabolic rate by 15%
a) I never advocated specifically a severely restricted calorie diet
b) A resting metabolic rate depressed by 15% does not preclude weight loss. Let’s grant, for arguments sake, that you do in fact lose 15% of your metabolic rate by dieting. Assume a man needing 2000 kcal / day for maintenance.
situation 1) Man burns 500 calories, 5 times a week while continuing to eat 2000 kcal / day. Net deficit is 2500 kcal / wk.
situation 2) Man drops to starvation diet of 1200 kcal /day. Base metabolism drops to 1700 kcal / day. Net deficit is 3500 kcal / wk.
…I still fail to see how situation 1 will come out ahead, in terms of weight loss alone. Overall health may be another story, but that’s a different topic.
But, you say - jogging will increase metabolic rate!
c) All of the restricted calorie groups in the studies you link lost a significant amount of body weight. This alone should be good evidence - calorie restriction -> weight loss. Unfortunately none of the studies in your link have a group who exercised alone and did not decrease caloric consumption compared to a group that did not exercise but practiced reduced calorie diets.
Look, I’m not trying to rag on exercise. Like I said in my first post, exercise has lots of wonderful health benefits. But you haven’t answered my cites, that say that exercise alone simply won’t do as much as calorie restriction. If you are diligent about exercising, will you lose weight? Sure. But it’s simply not the most efficient path towards weight loss. It will improve your overall health, but the fastest way to a calorie deficit is simply not to eat them in the first place. And you don’t even need to adopt an extreme starvation diet - like the example I gave, just cutting out 350 kcal / day (which is really not hard) will put you energetically ahead of burning 500 kcal / day, five times a week. And I doubt it would lead to significant metabolic losses. Which, honestly, is easier to do?
All I said was that your simple calculation was invalid. You seem to be assuming I’m disagreeing with you to an extent I have not expressed.
You are correct that aerobic fitness will not of itself increase metabolic rate and I have expressed that badly.
The more muscle mass you have the more calories you will burn at rest. The studies you link to just show that increasing your fitness will not increase your metabolism per unit of non-fat mass. That is an interesting academic finding, but in the real world the more you exercise the more muscle you are likely to have and the more muscle you have the more calories you will burn overall (even if the rate per unit remains the same).
