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# Convert grams of fat in % of calories? (Read 105 times)

zitroo

How convert grams of fat in % of calories, my watch Beurer PM26, display at the end of workout, calories and grams of fat

In Beurer, non respondmy question.

THANKS.

Kilkee could prolly tell you how to do it. Or, maybe google it.

Labrat

A gram of fat burnt is about 9 calories, the math is simple from there.

5K  20:23  (Vdot 48.7)   9/9/17

10K  44:06  (Vdot 46.3)  3/11/17

HM 1:33:48 (Vdot 48.6) 11/11/17

FM 4:13:43 (Vdot 35.4) 3/4/18

protein & carbs 4 kcalories per gram   fat 9 per gram.

zitroo

To skyedog: 9 calories is when you ate a gram of fat, but not when you burn fat.

AmoresPerros

Options,Account, Forums

What if you put it in a melted marshmallow, and then put that and a square of chocolate between two graham crackers?

It's a 5k. It hurt like hell...then I tried to pick it up. The end.

strambo

For bonus pts, alcohol is about 7 cals per g.

How many calories of energy does a gram of body fat provide when burned?  Nevermind-easy google.  I knew a lb of body fat is worth about 3500 cals.  I never bothered to convert to grams.  A lb is 453.6 grams, times 9 cals is a little over 4,000.  Fat tissue is only about 87% fat, hence the lower 3500 cal estimate.

zitroo - I would guess your watch likely is using heart rate or pace to estimate the amount of total calories... and then also the amount of fat burned.   While running your body uses a mix of fuels for power - mainly sugars and fat - when doing very low intensity activity it is using a majority of fat... when getting up to an easy run... maybe 50/50%.... during a hard tempo run maybe 70% glycogen(sugar) and 30% fat...  everyone is different and the shift I don't think is very linear.

So if you go out and do a mellow 4mile run... burning 100cal per mile.... it would then say 400 calories total.... 200 calories of fat or ~22 grams of fat    However, the amount of fat would be fairly big guesstimate - as fat oxidation rates are very variable among a group of people.  If the watch doesn't have a barometric altimeter for elevation... the calories would also be very off on a hill climb...etc.   Also footing and terain would effect work done as well.

5k: 19:29  Oct'17      26.2:  4:03 Oct'15  3:22 Grandmas June'17       Upcoming: Grandmas Marathon June'18

runktrun

So if you go out and do a mellow 4mile run... burning 100cal per mile.... it would then say 400 calories total.... 200 calories of fat or ~22 grams of fat    However, the amount of fat would be fairly big guesstimate - as fat oxidation rates are very variable among a group of people.

This.  I guess I'm curious WHY you want this data.  Knowing your intent may get you a better answer.

Not running for my health, but in spite of it.

I can imagine the curiosity could come from... wow - i just burned 1500 calories on a long run.... i "need" to refuel/recover, eat big!... so that i'm hopefully restored as best I can for my hard workout in a couple days.  However 1500cal is a lot... along with my 2000 cal diet.  But then I need to remind myself - that was 1500 cal of easier aerobic running (probably <50% from glycogen) so really I am in no need of 1500 to get back to 'even' in muscle glycogen - just 700 maybe.    A number presented on a watch or app could maybe shed light on that aspect of it.  Besides a basic... burned 1500.... aka "go eat all the food!"

In the end it might be helpful slightly or at least another indicator for someone looking to gain, lose, or maintain weight - where maybe hunger cues and long term weight trends alone haven't proven successful.

5k: 19:29  Oct'17      26.2:  4:03 Oct'15  3:22 Grandmas June'17       Upcoming: Grandmas Marathon June'18

strambo

All I know is I'm new to the endurance running world, but based on casual reading, interactions with marathoners I know, and a 25k race experience last week...it seems like endurance runners eat way too much junk food!

I mean, I did the 25k (muddy trail run) which started at 9am on nothing but coffee and water, skipping both aid stations and I was passing folks at the end (not fading or "bonking". )  When I finished, I'm not gonna lie, I enjoyed a 1/2 banana, cup of soup and a grilled cheese.  Most of all, about a pint and a half of micro-brew!  However, I wasn't all that hungry.

Seeing the big tubs of cookies, candy, chips etc. was a bit jarring...anyway it would be easy to out-eat any glycogen you actually burned during the run in that environment.

I'm pretty fat-adapted (generally eat low carb and I've done mulit-day fasts) so I'm approaching the nutrition angle from the opposite end.  How little can I eat and when will I bonk? Then, eat a little more than that.  I'm new enough at it that my long runs are neither long enough nor fast enough for me to bonk even in a fasted state.

Seeing the big tubs of cookies, candy, chips etc. was a bit jarring...anyway it would be easy to out-eat any glycogen you actually burned during the run in that environment.

Seems like that is true (agree for a 25k...) - but really most people can NOT and do not eat their way safely through a long race bonk.  Humans can generally only metabolize and use a certain amount of ingested sugar per hour. (~60g carb/HR lets say)  However that number goes further down during periods extended exertion (race pace) due to lowered bloodflow to digestive track, stomach quizeness while running, dehydration, etc.   There have been quite a few studies showing that as well as 'wasted' sugars that pass through system late in races.  You can train your body to better use fuel late in races by practicing it.   However if you are running a brisk pace at 100-150cal per mile... possibly burning 1040calories in an hour (7.5min miles at 130cal).... even at a 'fat adapted' 50/50 split at race pace that is +500cal of sugars.  After a few hours your ~1600cal of glycogen is very low or gone...bonk symptoms have already started a mile or two back!!!  At this point your body can't use sugar effectively...plus a ingest vs availability lag.... enjoy the struggle...

solid article on topic: https://minneapolisrunning.com/3-things-know-fueling-marathon/

Trying to get enough solid food into a stomach while at a hard race pace... eek.   Most people would never be able to keep that up!

I do agree that running more runs 'low' without fuel and also trying to skirt the wall occasionally in training (early surges in long run, high caffeine).  Sure seems like a smart route to hopefully shift your fuel use from maybe a typical 60gly/40%fat at race pace... to maybe 40%sugar/60%fat... however, iirc numerous studies have shown that 'fat adapted' vs high carb users... have similar/same marathon results.   However some other studies have shown in substantial other benefits to training 'low' (one great example was cycling...one leg always fully fueled... other leg same workouts, glycogen depleted).

During endurance events - working hard as possible (maybe harder then recommended at times) - will shift your fat/sugar burn curve towards more sugars... so eating as much food as comfortable, creates a method to run faster then your aerobic system would be able to do otherwise.  Things like sugars/starches are fairly easily digested and usable making it even more possible to keep up with a high calorie burn.

5k: 19:29  Oct'17      26.2:  4:03 Oct'15  3:22 Grandmas June'17       Upcoming: Grandmas Marathon June'18

strambo

^^^^^^^Good post and article, thanks!