Calories burned during exercise: don't trust anyone?

Yes, these estimates are always going to come with a margin of error. The labels on our food have margins of error. There is human error when we eyeball or weigh things or even with our data entry.

You just have to pick a starting point. Enter in the numbers (with a grain of salt), and observe what happens over time (say 4-8 weeks). If you're trying to lose 1 lb per week, but in reality you're losing too fast or slow, then you can tweak your calories up or down. After a few rounds of this, you will be well dialed in, and as long as you're consistent in your behavior, the errors essentially get rounded out.

It's uncanny how your weight loss or weight gain can work like clockwork once all your numbers are dialed in - even knowing that there is margin of error involved.

Edit: for example, I have my calories set to 2500 right now, and log everything I eat. But I eyeball some things and I'm pretty sure I'm eating a little bit more than what's actually logged. I also record my workouts, including weight training, with my HRM. It is commonly accepted that HRMs overestimate calories burned during weight training. But I enter what the HRM says and "eat back" those calories as well - so again, I'm going above what I "should" be eating. But it all works out and the reason is that the 2500 that I'm starting with is likely a conservative/low estimate. In reality, I'm probably baselining at 2800. But I've been doing this long enough that I have my routine and I get my expected results. And I don't sweat those absolute numbers all that much; just the relative changes I make every few months.

The MFP and lots of other exercise calorie data is, as you say, dodgy.

The best way I've found to estimate calories (short of doing what you did) is based on heart rate.

Here is calorie data from the medically supervised program where I lost most of my weight:

http://www.hmrprogram.com/index.cfm/DietTools/Walk-O-Meter (look at the "Calories for any Activity" tab on the right.)

I mapped their categories to heart rate: Low intensity = 60 to 69% of Max HR; Med. Intensity = 70 to 79% of Max HR, etc.

These guidelines have served me very well.

Bump. I'm interested to hear others' responses...

Interesting. I've followed MFP's calorie recommendation, used the gym machines to give me the calories burned and eat back almost all my calories (I was eating them all back until the last couple of days and since I am heading into my last 20 lbs to lose I have added 200 calories a day and am still trying to convince myself it's okay to eat them) and I have been losing weight steadily. Not fast, but steadily. Since I joined MFP in March, I have lost 15 lbs, I lost the rest in the few months before using another site. I think it's pretty accurate on my calories allotted and calories burned. But I am also not in a race to lose weight, so I'm okay with losing it slowly.

bump

Yes, these estimates are always going to come with a margin of error. The labels on our food have margins of error. There is human error when we eyeball or weigh things or even with our data entry.

You just have to pick a starting point. Enter in the numbers (with a grain of salt), and observe what happens over time (say 4-8 weeks). If you're trying to lose 1 lb per week, but in reality you're losing too fast or slow, then you can tweak your calories up or down. After a few rounds of this, you will be well dialed in, and as long as you're consistent in your behavior, the errors essentially get rounded out.

It's uncanny how your weight loss or weight gain can work like clockwork once all your numbers are dialed in - even knowing that there is margin of error involved.

Edit: for example, I have my calories set to 2500 right now, and log everything I eat. But I eyeball some things and I'm pretty sure I'm eating a little bit more than what's actually logged. I also record my workouts, including weight training, with my HRM. It is commonly accepted that HRMs overestimate calories burned during weight training. But I enter what the HRM says and "eat back" those calories as well - so again, I'm going above what I "should" be eating. But it all works out and the reason is that the 2500 that I'm starting with is likely a conservative/low estimate. In reality, I'm probably baselining at 2800. But I've been doing this long enough that I have my routine and I get my expected results. And I don't sweat those absolute numbers all that much; just the relative changes I make every few months.

This is excellent. I wish more people could read this and comprehend what you're actually trying to get across.

Ok, how important is it to eat back the workout calories? I need to lose about another 30 pounds so there are plenty of fat stores for my body to use when I am in a calorie deficit at the end of the day (which I almost always am). I have read that it's not as important to eat back the exercise calories until to get close to your target weight. I ask because I am concerned about my metabolism getting jacked around.

I use a heart rate monitor too and after an hour of cardio it says I burned 800 cals. That really seems like a lot to me so I usually split it in half.

I am tending to agree with most here in that everyone is different and it's really a matter of proper tracking and analysis to determine what works best for you.