Tucker - it turns our that metabolic efficiency is relatively low to put out the work that you measure in kJ - somewhere between 20-25% (as I understand it; I am not an expert). That's why Penny says you can't directly use kJ as energy expended.
The conversion between kJ and kCal is 4.184, so for very round numbers, turning the kJ recorded into kcal (or Cal) is not too bad of an approximation in general - that's the approximation you refer to. I am surprised that the Garmin came up with a number that's twice the size rather than just "somewhat larger". That sounds anomalous to me, but I don't have a good explanation.
William that is the number I was looking for. So essentially it appears that the calories expended on the bike is 1.2 * kJ. That is what I have been using instead of what the garmin says. But now Penny says to use the Garmin. So on yesterdays ride the Garmin tells me I burned around 1300 calories in an hour. kJ were 650ish. Again the Garmin has doubled the kJ. Is anyone else seeing this kind of difference? Penny you say use the garmin. Now I had watched a tv report claiming that all of these watches and workout machines overestimate by at least 20%. Do you agree?
I have occasionally gotten very different numbers straight off the Garmin and even using Garmin's software or other third party software. So, to be honest, I don't try to track it to the 100-Cal precision (though I know this is useful). I usually figure that at reasonable intensity, everything is in the neighborhood of 800 Cal/hr and then I adjust from there.
William that is the number I was looking for. So essentially it appears that the calories expended on the bike is 1.2 * kJ. That is what I have been using instead of what the garmin says. But now Penny says to use the Garmin. So on yesterdays ride the Garmin tells me I burned around 1300 calories in an hour. kJ were 650ish. Again the Garmin has doubled the kJ. Is anyone else seeing this kind of difference?
Penny you say use the garmin. Now I had watched a tv report claiming that all of these watches and workout machines overestimate by at least 20%. Do you agree?
Honestly, I'm not comfortable determining calories burned from KJ of work. I do not agree that the watches overestimate but do that the machines do. The only way to really know how much you are expending is to do all of your workouts hooked up to a metabolic cart. I'm more comfortable using the watches and/or comparing it with METs. Here is a website that does the per hour calculation based on METs: http://www.acaloriecalculator.com/calories-burned-calculator/. ; METs aren't perfect, but they are a good starting point.
I think the take home message is to not get too wound about every calorie eaten and expended. Yes, you can track them but they are not going to be perfect. All of this stuff is best guess. The best way is to pay attention to how your body feels and your weight.
I've posted to the sports RD listserv to see if anyone there has ideas on the KJ vs. calories issue. I'll let you know as soon as I hear back from them.
Thanks Penny. I am not trying to be too anal about this, but the fact that I am getting a 2 to 1 ratio between Garmin to Powertap has me looking for the more correct answer.
thanks, Penny! Good questions Tucker... I have often wondered about my Garmin... and I guess I figured that I programmed my height, and HR zones, etc... it should be in the ballpark. So, I'm sticking with that. I've noticed that when I enter the workouts in LoseIt, LoseIt usually guesstimates a tad low, but I stick with that number.
So far so good with me (but Fri is always my low weigh in day)... dropping while eating more than 800 cal per day. a lot more... but the net is in the 1300-1500 range, so I'm good with that.
Thanks Penny. I am not trying to be too anal about this, but the fact that I am getting a 2 to 1 ratio between Garmin to Powertap has me looking for the more correct answer.
Thanks Penny. I am not trying to be too anal about this, but the fact that I am getting a 2 to 1 ratio between Garmin to Powertap has me looking for the more correct answer.
Tucker: I see what you are saying, but you can't equate KJ of work generated to calories burned. Apples and oranges. Let's say we have two people, one highly trained and one just starting out. The highly trained athlete generates 1000 KJ of work and burns X calories. For the less trained person to generate 1000 KJ of work it is going to take more calories because his body isn't used to the workouts, his body hasn't made the adaptations to burn fuel as efficiently as the highly trained person, etc. Does that help?
If the PT is reporting calories burned as KJ, then that is another thing entirely.
For you power Tap users, Allen Lim (Garmin-Transition and now Radio Shack creator of the powertap blah blah) has this to say:
When I do a ride with my PowerTap I can easily find the total number of joules for the ride. Since 4.2KJ is approximately equal to 1Kcal, and the metabolic efficiency when cycling is usually 20-25%, you get a 1:1 relationship between KJ and expended Kcal, e.g. a 1500KJ ride means that my caloric expenditure is roughly 1500Kcal.
For you power Tap users, Allen Lim (Garmin-Transition and now Radio Shack creator of the powertap blah blah) has this to say:
When I do a ride with my PowerTap I can easily find the total number of joules for the ride. Since 4.2KJ is approximately equal to 1Kcal, and the metabolic efficiency when cycling is usually 20-25%, you get a 1:1 relationship between KJ and expended Kcal, e.g. a 1500KJ ride means that my caloric expenditure is roughly 1500Kcal.
Second slide down explains the relationship. The power tap will always be pretty close. The only variable in it is your cycling efficiency, which sits in a pretty narrow range across lots of different studies. Bottom line is that to do 1000 kj of work requires between about 950 and 1050 calories, regardless of your weight, etc. Unless you have a thermodynamic efficiency that is an outlier (which is why Penny is right to say that the only truly accurate way to know).
Since, for basic health maintenance, accuracy should take a back seat to 'close enough', the powertap should be the data of choice, as it is usually going to be pretty close. The garmin may or may not be, for a variety of reasons. If you don't have a power tap, then the garmin is better than nothing. But if you have a power tap, use the kj number for your calories.
That Lose It! app has made a ton of difference for me . . . well, 3 pounds in the last week. Logging it makes all the difference. Here's the hard part. I have it on a 2 lbs per week loss and that means 1175 calories a day net. That is hard on a rest day. Makes me eager for Friday/Saturday when I get 1200 to 1500 calories of workout. I never eat as many calories as I burn on those days. I'm tempted to move a couple hundred over to Monday when I'm recovering, but so far I'm sticking to the discipline of each day standing alone. Down to 147, looking for 132.
I was in a similar boat of never being able to take in enough calories on one day... My nutritionist said it was fine to move a couple hundred to the next day (or even spread it over two days). I hated feeling like I was trying to stuff myself and then feel hungry the next day. Why feel all out of whack, right? It doesn't always just take one day to recover, so why not eat accordingly? Just my two cents... hope it helps you out!
I did not read through all the postings so perhaps this has been mentioned... Another good way to go is with a bodybugg. For those that like the "game" aspect of keeping calories under control it is pretty fun. If you've ever watched the biggest loser, this is what they are all wearing on their arms. It is a small band that has sensors. It tracks movement, heat, and other "stuff" and calculates your calorie burn based on that. It also has a very good food tracker with lots of stuff in it.
The biggest weakness I've found is you have to pay for it. The arm band is a couple hundred I think and then you need a subscription to the site. The subscription is pretty cheap. Anyway, I've dropped from 260 to 200 with it...and am going to hit 185 in a couple months if I don't eat a bunch of brownies. I really like using it and update my food a few times a day. I believe it also has apps for the bb and iphone.
Another important thing I've noticed...I've found I can maintain a 2lb/week weight loss just so long as I eat enough calories to maintain my normal daily calroie burn. Not the little tiny base metabolism number...I'm talking about the number you'd burn if you didn't work out that day. So if my base metabolism is 1600 calories at 6'2, 200lbs...my normal day has me burning about 2600-2700. (Those are actual numbers for me). Doing that I can still get faster and lose weight at the same time.
My goal for all workout days is to eat around 2700 calories and use the workout calories as my weightloss. If I go on a really long ride or something like that I will increase my calories for the day too. I just notice a defecit that was too big caused some weaknesses both mentally and physically. On days I don't workout, of which there will now be 2, I just try to maintain or have a slightly smaller defecit.
iphone users: my lose it app just crashed, froze. all i see is a blank grey screen now when i click on it. what do i do? i've only had the phone a week, so i'm clueless. thanks, Keith
my lose it app just crashed, froze. all i see is a blank grey screen now when i click on it. what do i do? i've only had the phone a week, so i'm clueless.
thanks,
Keith
Sometimes powering the phone off works to reset it. Otherwise, check and make sure you have the latest updates to the program. After that I'd uninstall it and then reinstall it. After that, you'll want to contact ATT/Apple cause it's probably not the program (I just checked mine and haven't had any recent issues.)
I read Racing Weight. It does have some good ideas, but not the magic bullet I hoped for. :-) (OK, that's not fair...)
For example, his way of determining your best racing weight is basically to race at several weights and see where you do the best.
He asserts some things that I've read at least the secondary literature are wrong without citing much primary literature and is big into nutrient timing. If you buy into that or are willing to, he gives you some good practical advice. There is other good practical advice about managing your eating and nutrition profile. It's definitely not going to be a favorite of those who are big into the paleo diet, either.
Bottom line: worth a read, and it's not too expensive from Amazon. Free from the library. Don't expect miracles.
yes paul, there is a version i like better by the CoreDiet nutritionist I used, she is re-enabling a link for me. I think rich's was really good and want my daughter to listen to it!
yes paul, there is a version i like better by the CoreDiet nutritionist I used, she is re-enabling a link for me. I think rich's was really good and want my daughter to listen to it!
If I did this you'd find it either on our Podcast Channel or our YouTube channel. Considering that it's the day before Thanksgiving and Kandi called me "juicy" and that my junk is back in the trunk, I may want to redo this anyway, to get my mind right...
did a quick search of those places with no luck, but wil look again - as my daughter asked for a donut on the way home from the turkey trot, I really wanted to just play your line about the exercise earning you the right to eat nutrient dense foods! by all maens get a great video out there!
How and where do I get on the body composition tracker/challenge? I know I saw it but now I'm having trouble locating it again. Is there someone to sign up with?
Comments
The conversion between kJ and kCal is 4.184, so for very round numbers, turning the kJ recorded into kcal (or Cal) is not too bad of an approximation in general - that's the approximation you refer to. I am surprised that the Garmin came up with a number that's twice the size rather than just "somewhat larger". That sounds anomalous to me, but I don't have a good explanation.
Penny you say use the garmin. Now I had watched a tv report claiming that all of these watches and workout machines overestimate by at least 20%. Do you agree?
Honestly, I'm not comfortable determining calories burned from KJ of work. I do not agree that the watches overestimate but do that the machines do. The only way to really know how much you are expending is to do all of your workouts hooked up to a metabolic cart. I'm more comfortable using the watches and/or comparing it with METs. Here is a website that does the per hour calculation based on METs: http://www.acaloriecalculator.com/calories-burned-calculator/. ; METs aren't perfect, but they are a good starting point.
I think the take home message is to not get too wound about every calorie eaten and expended. Yes, you can track them but they are not going to be perfect. All of this stuff is best guess. The best way is to pay attention to how your body feels and your weight.
I've posted to the sports RD listserv to see if anyone there has ideas on the KJ vs. calories issue. I'll let you know as soon as I hear back from them.
thanks, Penny! Good questions Tucker... I have often wondered about my Garmin... and I guess I figured that I programmed my height, and HR zones, etc... it should be in the ballpark. So, I'm sticking with that. I've noticed that when I enter the workouts in LoseIt, LoseIt usually guesstimates a tad low, but I stick with that number.
So far so good with me (but Fri is always my low weigh in day)... dropping while eating more than 800 cal per day.
a lot more... but the net is in the 1300-1500 range, so I'm good with that.
Does your PT give you calories or KJ?
@Penny: PT reports KJ
Tucker: I see what you are saying, but you can't equate KJ of work generated to calories burned. Apples and oranges. Let's say we have two people, one highly trained and one just starting out. The highly trained athlete generates 1000 KJ of work and burns X calories. For the less trained person to generate 1000 KJ of work it is going to take more calories because his body isn't used to the workouts, his body hasn't made the adaptations to burn fuel as efficiently as the highly trained person, etc. Does that help?
If the PT is reporting calories burned as KJ, then that is another thing entirely.
For you power Tap users, Allen Lim (Garmin-Transition and now Radio Shack creator of the powertap blah blah) has this to say:
@Hayes: Thanks for posting that!
http://www.cycleops.com/power-basics.html
Second slide down explains the relationship. The power tap will always be pretty close. The only variable in it is your cycling efficiency, which sits in a pretty narrow range across lots of different studies. Bottom line is that to do 1000 kj of work requires between about 950 and 1050 calories, regardless of your weight, etc. Unless you have a thermodynamic efficiency that is an outlier (which is why Penny is right to say that the only truly accurate way to know).
Since, for basic health maintenance, accuracy should take a back seat to 'close enough', the powertap should be the data of choice, as it is usually going to be pretty close. The garmin may or may not be, for a variety of reasons. If you don't have a power tap, then the garmin is better than nothing. But if you have a power tap, use the kj number for your calories.
Mike
That Lose It! app has made a ton of difference for me . . . well, 3 pounds in the last week. Logging it makes all the difference. Here's the hard part. I have it on a 2 lbs per week loss and that means 1175 calories a day net. That is hard on a rest day. Makes me eager for Friday/Saturday when I get 1200 to 1500 calories of workout. I never eat as many calories as I burn on those days. I'm tempted to move a couple hundred over to Monday when I'm recovering, but so far I'm sticking to the discipline of each day standing alone. Down to 147, looking for 132.
I was in a similar boat of never being able to take in enough calories on one day... My nutritionist said it was fine to move a couple hundred to the next day (or even spread it over two days). I hated feeling like I was trying to stuff myself and then feel hungry the next day. Why feel all out of whack, right? It doesn't always just take one day to recover, so why not eat accordingly? Just my two cents... hope it helps you out!
For those of us that don't have an iphone, LoseIt! is available online for free at: www.loseit.com
Another good way to go is with a bodybugg. For those that like the "game" aspect of keeping calories under control it is pretty fun. If you've ever watched the biggest loser, this is what they are all wearing on their arms. It is a small band that has sensors. It tracks movement, heat, and other "stuff" and calculates your calorie burn based on that. It also has a very good food tracker with lots of stuff in it.
The biggest weakness I've found is you have to pay for it. The arm band is a couple hundred I think and then you need a subscription to the site. The subscription is pretty cheap. Anyway, I've dropped from 260 to 200 with it...and am going to hit 185 in a couple months if I don't eat a bunch of brownies. I really like using it and update my food a few times a day. I believe it also has apps for the bb and iphone.
Another important thing I've noticed...I've found I can maintain a 2lb/week weight loss just so long as I eat enough calories to maintain my normal daily calroie burn. Not the little tiny base metabolism number...I'm talking about the number you'd burn if you didn't work out that day. So if my base metabolism is 1600 calories at 6'2, 200lbs...my normal day has me burning about 2600-2700. (Those are actual numbers for me). Doing that I can still get faster and lose weight at the same time.
My goal for all workout days is to eat around 2700 calories and use the workout calories as my weightloss. If I go on a really long ride or something like that I will increase my calories for the day too. I just notice a defecit that was too big caused some weaknesses both mentally and physically. On days I don't workout, of which there will now be 2, I just try to maintain or have a slightly smaller defecit.
Anyone ever read Racing Weight by Matt Fitzgerald and if so what are your opinions.
my lose it app just crashed, froze. all i see is a blank grey screen now when i click on it. what do i do? i've only had the phone a week, so i'm clueless.
thanks,
Keith
Sometimes powering the phone off works to reset it. Otherwise, check and make sure you have the latest updates to the program. After that I'd uninstall it and then reinstall it. After that, you'll want to contact ATT/Apple cause it's probably not the program (I just checked mine and haven't had any recent issues.)
For example, his way of determining your best racing weight is basically to race at several weights and see where you do the best.
He asserts some things that I've read at least the secondary literature are wrong without citing much primary literature and is big into nutrient timing. If you buy into that or are willing to, he gives you some good practical advice. There is other good practical advice about managing your eating and nutrition profile. It's definitely not going to be a favorite of those who are big into the paleo diet, either.
Bottom line: worth a read, and it's not too expensive from Amazon. Free from the library. Don't expect miracles.
Thanks William. Is EN a big supporter of the Paleo Diet?
The "lots of veggies" diet in all its forms won't steer you wrong around here. :-)
If I did this you'd find it either on our Podcast Channel or our YouTube channel. Considering that it's the day before Thanksgiving and Kandi called me "juicy" and that my junk is back in the trunk, I may want to redo this anyway, to get my mind right...
did a quick search of those places with no luck, but wil look again - as my daughter asked for a donut on the way home from the turkey trot, I really wanted to just play your line about the exercise earning you the right to eat nutrient dense foods! by all maens get a great video out there!
How and where do I get on the body composition tracker/challenge? I know I saw it but now I'm having trouble locating it again. Is there someone to sign up with?
TIA!
Patti