Can anybody give me a good explanation as to how exercise helps one lose weight?

I have blind friends who run marathons, ski, complete Tough Mudders, and climb mountains. There are a lot of resources out there if you’re interested.

I don’t know the science, but I like to think of it this way:

My body is an extremely complex machine. If I pretend to understand special details of how it works, or if I subscribe to theories that do such pretending, I will be limiting my success to the weakest points of the pretentious theorizing. Instead, I do my best to stick to what is both general in scope and provable without the latest theory.

Eating like Stranger described, works. Exercise to me is not a science, it’s a little box that either has a check mark in it or doesn’t. Whatever we may think we know about how exercise works, we know for sure that not exercising is bad. If you eat reasonably, and if there’s a check mark in your “exercise” box, it’s enough. The rest is only for bonus points.

I’d say its number 4 mostly. Diet and exercise work synergistically. You become motivated to eat better things as you do better things with your body. And as this synergistic energy produces tangible results, it provides continuing motivation to stay on track.

Exercise also consumes time that might otherwise be spent eating.

Seriously. My brother lost 117 pounds about twenty five years ago and has kept it off ever since, by replacing his habit of sitting on the couch eating cookies and junk food with first walking, then jogging, then marathons, then triathlons. (And getting tattoos.)

A tribute to the power of positive addictions.


Here is another source for what I am sure is the same information:

Simply put burning fat makes H2O and CO2. And most of the fat is lost thru respiration not sweat.

Blood glucose is our body’s chief source of moment-to-moment energy, with glycogen stored in the liver the second reserve. My understanding is that sustained aerobic exercise (anything you can do for twenty minutes or more) is required before our muscles start utilizing fat as an energy source.

My body follows the Winnie the Pooh Process:

*When I up, down, touch the ground
It puts me in the mood
Up, down, touch the ground
In the mood (smacks lips) for food

I am stout, round and I have found
Speaking poundage-wise,
I improve my appetite
When I exercise

I just get hungrier when I exercise!

I got to get me some of those :proteins. They sound yummy.

Reminds me of the Porky Pig cartoon “Bye Bye Bluebeard”, which opens with Porky following along with an exercise program- “Down! Up! In! Out!”- by moving his fork between his laden plate and his mouth.

I like this analogy I heard the other day:

The pan is your body.
The butter in the pan is the fat on your body.
Exercise is the heat underneath the pan that melts the butter away.

Post snipped, bolding mine. This assumes that the body treats all foods the same.

It doesn’t work that way and, imho, the idea that all calories are equal is one of the main reasons people struggle to lose weight.

Carbs are processed differently than fats and proteins. Link.

Additionally, insulin is released to digest carbs. More carbs == more insulin. Insulin slows down the breakdown of fat.

So, no, a calorie isn’t just a calorie. What form the calorie takes is important.


I am growing to enjoy going to the gym, and I would absolutely hate being tethered to another runner or biker.

“Losing weight” is tough. First of all, most people want to lose fat but not muscle–but the body will happily burn muscle if you just cut calories. Second, when you start cutting calories from your diet, your metabolic baseline can drop so you then burn fewer calories at rest. Exercise burns calories directly, and also increases your basal metabolism.

Does it work as sort of an adjunct to losing weight for the currently fat and sedentary? Probably, and it’s probably also true that a nice moderate amount of excercise is better than heavy exercise. I suspect it’s also true that continuous activity is better than is a 30-minute burst followed by 23 1/2 hours of sitting on your ass.

Here is an interesting (small) study looking at whether adding an exercise regimen helps young overweight men lose weight.

The exercise increases your basal metabolism even at rest story is likely as true as you using only 10% of your brain.
If you are routinely burning more sugar or fat, you are producing more heat, and your temperature should go up.
I’ve seen no evidence that trained athletes run a continuously higher body temperature than regular people.
98.6°F is the standard, regardless of how fit you are.
You want to lose weight, cut Calories. That 60 Calories you run on a treadmill each day won’t even compensate for a single cooked egg, and it’s not going to turn your body into a fat burning machine. That would give you a fever.


The body’s heat dissipation system is adaptive.

If you get warmer you sweat, if you get colder you shiver. The flow of blood to your skin is also increased or decreased. It works really, really hard at maintaining an even temp. Body temperature is not an accurate measure of how many calories you are burning.

Here, learn about thermogenesis:

If an exercise regimen were to up your basal metabolism to require an extra 2000 Calories to maintain weight just sitting around, you’d get hot.
The system’s adaptive but it’s not all that adaptive.

The links do not in any way support an increase in body temp based on fitness.

Note you wrote:

“I’ve seen no evidence that trained athletes run a continuously higher body temperature than regular people.
98.6°F is the standard, regardless of how fit you are.”
Notice the “continuously”! You may get a bit warmer during exercise but otherwise your body temp will be the same regardless of fitness level. (Ignoring weird extremes like starving people on the verge of dying.)

Producing more heat doesn’t automatically mean higher temperature when you have a system well designed to shed or conserve heat as needed.

Burning more calories everyday should generally not increase ones body temperature.


Huh? EPOC (Excess post-exercise oxygen consumption) certainly does happen. You have to execise a lot to get the effect, so the recommended “half hour of moderate exercise three times a week”, or whatever they’re recommending these days, will not do it. You have to change that “moderate” to “vigorous” and increase the time by at least 15 minutes.