An interesting thing my dietition told me

mrogers52

Thank you for taking the time to share this information with us!:glasses:

Zeromilediet

That is a physiological concept I have never heard of. The metabolic demands of exercise pretty much override everything else. Performance might suffer if you don't have enough stored glycogen or circulating glucose, but you won't "conserve" fat. You actually switch to more fat, which is why performance suffers. Unfortunately, that switching to more fat doesn't help w/permanent fat loss.

^^^this^^^
If you don't have adequate circulating blood glucose during exertion, the body will use stored fat--that's the whole reason humans have fat: stored energy (muscle is not used as an energy source except when there's not enough stored fat); therefore it's better to exercise on an empty stomach. After exercising, have a low-glycemic breakfast for the most satiety and fat burning.

From: http://jn.nutrition.org/content/139/5/890.short
© 2009 The American Institute of Nutrition
Fat Oxidation during Exercise and Satiety during Recovery Are Increased following a Low-Glycemic Index Breakfast in Sedentary Women1,2
Emma J. Stevenson * , Nerys M. Astbury, Elizabeth J. Simpson, Moira A. Taylor, and Ian A. Macdonald
School of Biomedical Sciences, University of Nottingham, Nottingham NG 7 2UH, UK

Abstract
Consuming low-glycemic index (LGI) carbohydrates (CHO) before endurance exercise results in increased fat oxidation during exercise in trained men and women. It is not known if this phenomenon occurs during low intensity exercise and in untrained participants. We examined the effects of breakfasts containing high-GI (HGI) or LGI foods on substrate utilization during rest and walking exercise in sedentary women. The metabolic and appetite responses to a standard lunch consumed after exercise were also investigated. Eight healthy sedentary women completed 2 trials. On each occasion, participants were provided with a HGI or LGI breakfast 3 h before walking for 60 min. Following exercise, participants were provided with lunch and remained in the laboratory for a further 2 h. Plasma glucose and serum insulin responses (area under the curve) were higher following the HGI breakfast than following the LGI breakfast (P < 0.05). During the 3-h postprandial period, fat oxidation was suppressed following both breakfasts but remained higher in the LGI trial (P < 0.05). During exercise, total fat oxidation was also greater in the LGI trial (P < 0.001). There were no differences in the metabolic responses to lunch. Participants reported feeling fuller following lunch in the LGI trial (P < 0.05). Consuming a LGI breakfast increases fat oxidation during subsequent exercise and improves satiety during recovery in sedentary females.

lipsticknlattes

I don't eat before I workout. If your body doesn't have food to burn through, it will use the FAT on your body for fuel. I've lost 20 pounds and am in excellent shape. I would vomit if I worked after I ate breakfast. I have a cup of coffee, workout, then breakfast.

McghanK

So...do you have to eat before you work out? I work out at 5am and then I eat a few hours after. So is this wrong? I can't really get myself to eat at 4:45 when I get up and I have to be at work by 7....suggestions?

It's up to you. I get up at 5 am also. I walk our 3 dogs, eat breakfast, go for a 3 mile run, shower and have to be at work by 7 also. (My hubby gets to take care of getting the kids to daycare in the morning so he's the best :happy:)

Wow, good for you! I don't have time unless I want to get up earlier. My commute is about 45 minutes and we carpool so I have to be at the carpool place by 6:30. So I wake up 4:45....excercise till about 5:40 take shower have something quick get in my car an go. Maybe a banana before will do ;0)

Losingitin2011

I don't eat before I workout. If your body doesn't have food to burn through, it will use the FAT on your body for fuel. I've lost 20 pounds and am in excellent shape. I would vomit if I worked after I ate breakfast. I have a cup of coffee, workout, then breakfast.

You're fortunate. If I try anything like that my blood sugar tanks and I either pass out or have to stop because I am about to pass out!

Frozenmango

That is a physiological concept I have never heard of. The metabolic demands of exercise pretty much override everything else. Performance might suffer if you don't have enough stored glycogen or circulating glucose, but you won't "conserve" fat. You actually switch to more fat, which is why performance suffers. Unfortunately, that switching to more fat doesn't help w/permanent fat loss.

^^^this^^^
If you don't have adequate circulating blood glucose during exertion, the body will use stored fat--that's the whole reason humans have fat: stored energy (muscle is not used as an energy source except when there's not enough stored fat); therefore it's better to exercise on an empty stomach. After exercising, have a low-glycemic breakfast for the most satiety and fat burning.

From: http://jn.nutrition.org/content/139/5/890.short
© 2009 The American Institute of Nutrition
Fat Oxidation during Exercise and Satiety during Recovery Are Increased following a Low-Glycemic Index Breakfast in Sedentary Women1,2
Emma J. Stevenson * , Nerys M. Astbury, Elizabeth J. Simpson, Moira A. Taylor, and Ian A. Macdonald
School of Biomedical Sciences, University of Nottingham, Nottingham NG 7 2UH, UK

Abstract
Consuming low-glycemic index (LGI) carbohydrates (CHO) before endurance exercise results in increased fat oxidation during exercise in trained men and women. It is not known if this phenomenon occurs during low intensity exercise and in untrained participants. We examined the effects of breakfasts containing high-GI (HGI) or LGI foods on substrate utilization during rest and walking exercise in sedentary women. The metabolic and appetite responses to a standard lunch consumed after exercise were also investigated. Eight healthy sedentary women completed 2 trials. On each occasion, participants were provided with a HGI or LGI breakfast 3 h before walking for 60 min. Following exercise, participants were provided with lunch and remained in the laboratory for a further 2 h. Plasma glucose and serum insulin responses (area under the curve) were higher following the HGI breakfast than following the LGI breakfast (P < 0.05). During the 3-h postprandial period, fat oxidation was suppressed following both breakfasts but remained higher in the LGI trial (P < 0.05). During exercise, total fat oxidation was also greater in the LGI trial (P < 0.001). There were no differences in the metabolic responses to lunch. Participants reported feeling fuller following lunch in the LGI trial (P < 0.05). Consuming a LGI breakfast increases fat oxidation during subsequent exercise and improves satiety during recovery in sedentary females.

I think I was misunderstood...my dietician didn't say that you wouldn't burn fat AT ALL, her point was that your body will hold back on its maximum burning potential, if you will, if you don't fuel yourself properly throughout the day. Most of us here who are trying to lose weight would like to burn at the best potential we can, so this tidbit is to hopefully helpful.

And for those worrying about eating right before a workout, that is totally up to you/based on how you feel. Some people do a lot better with a quick snack before they workout, others don't need it.

@McghanK - you don't necessarily have to have a meal before you do your morning workout, but since you mentioned that you work out right after waking up (after your body's gone without food for around 6 hrs or more) it would probably help you if you had a small snack, like a banana, and apple, some yogurt with fruit in it or a small shake to get your blood sugar level up and your metabolism going. But if you really don't feel that you need it, making sure you're eating properly the rest of the day is just fine