I cut and pasted this from the 100-pound club, but I think my questions were probably a little too technical for that forum, and Idealmuse suggested I post them here. I know it's a lot of questions, but I'd appreciate any answers to any of them. I actually have gotten some good suggestions about what to wear when I walk/run in the cold weather, but I would love any additional suggestions, especially if they are things that have worked for you. I've also added a question about my sister.

Here's the original post:

There has been a lot of discussion about exercise and burning calories on different threads, and I have been thinking about it. Since my questions are an amalgamation of different threads, I thought I would just start a new one.

In response to a question by Cara, Meg mentioned that calories burned are more accurately determined based on heart rate than on a machine print-out. Having seen the variations in different machines when it felt like my effort was similar, I was not at all surprised to hear it. However, it made me wonder - I have been really excited to watch my resting heart rate go down as a result of my consistent exercise. Does this mean that because I'm getting in better shape, I'm burning fewer calories when I'm not exercising? Also on that same line, doesn't weight fit into the formula somewhere for how many calories are burned? The heart rate variable seems to make sense to me, but doesn't the heart have to work harder to push blood through all of the extra mass of a larger person? Thus, wouldn't a person at a higher weight burn more calories than a person at a lower weight, even when they had identical heart rates?

I also have heard a lot about a "fat burning" zone. On the stationary bike that I ride, it tells me whether I'm working out in the "fat burning" zone, the "aerobic" zone, the "endurance" zone, or the "training" zone. Since I think it's better to push myself as hard as I can, I spend most of my time in the "endurance" zone. Does this mean that I'm burning less fat than if I reduced my effort?

And, finally, I hate to be posting a cold weather exercise question this early in the season, but it's been really chilly here lately. I went on my walk / run last night, and it was about 30 degrees. I started out in a coat - and was freezing even then! - then as my body temperature went up, I opened the zipper, then took the coat off. At the end, my core temperature was warm, but my extremities, particularly my arms, were uncomfortably cold. Any thoughts on the best work-out gear for outside in the cold weather? I can't stand wearing sweats when I work out - I don't like to be uncomfortably warm, and it inevitably happens when I wear sweats.

And, my sister's question:

She is about 235 pounds, having lost about 15 from diet alone. She added in exercise last Saturday, and is walking about an hour a day in an area with lots of hills. She says she is completely exhausted by the walks, to the point that she could fall asleep at any time of day. I asked about TOM, whether her walks were so strenuous she couldn't speak, and her previous fitness level. She said it wasn't TOM, the walks weren't overly strenuous, and her fitness level - while not great - wasn't sedentary either. I also asked about whether she had simultaneously decided to highly restrict calories, and she said that she isn't doing that either. (In fact, she says she increased cals a bit when she started her exercise program.) So, I'm out of ideas. Any thoughts about how exercise - which has always really energized me - could cause these issues?

Very long post, I know. But I would love any wisdom regarding any or all of the questions above.

And I just read the "Top Ten Myths" sticky - again - and noticed that Meg had already answered the question about the intensity. Sorry. I guess I need to do a little bit of mind exercises to increase my retention of important information that I read on here.

I don't know the answer to a lot of your questions but I DO know about exercising in the cold! The key is to layer 2-3 tops, keep them all light weight and long sleeved, as you warm up you can take one off and tie it around your waist and still have long sleeves underneath. Also wear gloves and instead of a hat wear one of those ear bands to keep your ears warm.

For cold weather running I wear tights - thick ones, rather than sweats. I also wear gloves - my hands get colder than the rest of me. As wisher advised - wear a few long sleeved layers and that will help if you get too hot.

A relatively light windproof breathable top layer keeps the wind off but doesn't let you build up sweat inside. Undoing the zipper will help. Also keep with the synthetic wicking fabrics - avoid cotton (which many sweat pants are made of). Some places sell arm/leg warmers (not the 1970's type!) to put on over a shirt and keep those bits warm. I think they are mostly aimed at cyclists but you could use them if your arms are cold.

I do wear a hat when I run in the winter, not a big wool one, usually a fleece one. It keeps my head warm.

On your other question (calories burned) from what I know it's very difficult to estimate how much you're burning at any exercise. Yes, weight comes into it, if you are heavier then you'll burn more in weight bearing exercises - but your body also gets more efficient as it gets used to an activity so you burn less. There's also some research suggesting formerly obese people burn less calories in activity than never obese people - there are some great posts on that in the maintainers section. Check them out.

Stay warm,
Jax

I don't have answers to all your questions, but I do have answers for some.

Yes. Fitter people burn fewer calories during exercise. In part, this is because they have to work increasingly harder to get their heart rates up. Overweight people burn more calories than slim people during exercise, sitting around and sleeping. It takes more fuel to run a 250 pound body than it does to run a 150 pound body. That said, because muscle burns more calories than fat, muscular people have higher resting metabolic rates (RMRs) than people without much muscle tone.

The readouts on the exercise machines are really inaccurate. The ones that *should* be more accurate (but aren't always) are the ones that ask for your height, weight and gender; otherwise they're just giving data for a 150lb male. If you really want to be more certain about how many calories you're burning, you should look into buying a Heart Rate Monitor. Those are still not 100% accurate, because they can't gauge your fat-muscle ratio or your RMR, but they're pretty close. You enter your age, height, weight and gender and it estimates calories burned by tracking your heart rate. I LOVE mine. Couldn't do without it.

The best thing, however, is to keep on exercising and losing and exercising. It's just good for you.

My guess is that this is just about the body needing to adapt to the new regime. A 60 minute walk with lots of hills is a lot for a person who isn't used to getting much exercise. Whenever I have re-started exercising after a long hiatus and weight gain, I've spent the first few weeks tired and ravenously hungry after exercising. After a couple of weeks, the body adapts and the exercise eventually becomes energizing rather than exhausting. If she's really worried about it, she could cut the time a little bit--say, 30 or 45 minutes rather than 60, but eventually her body is going to need to get used to it.

She might also want to plan to have a carb and protein snack directly after her exercise, just to refuel the body.

Hope all that helps!

i really can only answer the cold exercise question. They key is to invest in good exercise appearal. They now make underlayers that wick sweat away while keeping you warm...and that is a biggggg key component. layers also help.