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Delphi
06-29-2003, 02:47 PM
I think I had been doing something good by drinking Gatorade with whey right after workouts, thinking I'd be getting in some quick protein as well as replacing glycogen stores. I looked on the label for the first time today and Gatorade is mainly sucrose and dextrose. I've heard some of y'all talking about taking fructose after a workout.

Fructose and glucose are monosaccharides

sucrose = fructose + glucose
dextrose = D-glucose

glycogen = chain of glucose molecules linked 1,4

From my understanding of this, fructose post-workout does nothing to restore glycogen. Is it going to help assimilate the whey protein?

Are there any sports drinks that have fructose, if so are they worth buying?

Blood&Iron
06-29-2003, 03:01 PM
Drinks like Gatorade are primarily intended for use during exercise. Typically, such drinks are quite dilute, generally being ~6% glucose/sucrose solution; they are not really intended as postworkout drinks (i.e. to replenish muscle glycogen)

Blood&Iron
06-29-2003, 03:10 PM
Some studies that, while not directly related to your question, should shed a little light on the subject:

(There are a ton more on PubMed)

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3285117&dopt=Abstract

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12739159&dopt=Abstract

bradley
06-29-2003, 05:12 PM
Originally posted by Delphi
From my understanding of this, fructose post-workout does nothing to restore glycogen. Is it going to help assimilate the whey protein?

You want some fructose post workout so as to refill liver glycogen. The status of liver glycogen (full or empty) is one of the factors in determining if the body is in an anabolic or catatbolic state. Also when you provide the body with fructose post workout it will allow more of the glucose to be used to refill muscle glycogen.



Are there any sports drinks that have fructose, if so are they worth buying?

I know Twinlab has a product called Ultra Fuel that contains a small amount of fructose.

Delphi
06-29-2003, 11:19 PM
Maybe I should just eat a couple of bananas?

bradley
06-30-2003, 03:06 AM
Originally posted by Delphi
Maybe I should just eat a couple of bananas?

The above would probably be fine, but I would go with maybe one banana along with a whey/malto shake.

http://www.wannabebigforums.com/showthread.php?s=&threadid=18019&highlight=bananas+post+workout

Maki Riddington
06-30-2003, 11:23 AM
*** Why consume fructose when glucose will do the job?

Effects of glucose or fructose feeding on glycogen repletion in muscle and liver after exercise or fasting.

Conlee RK, Lawler RM, Ross PE.

In athletics, muscle and liver glycogen content is critical to endurance. This study compared the effectiveness of glucose and fructose feeding on restoring glycogen content after glycogen was decreased by exercise (90-min swim) or fasting (24 h). After 2 h of recovery from either exercise or fasting there was no measurable glycogen repletion in red vastus lateralis muscle in response to fructose. In contrast, glucose feeding induced a similar and significant carbohydrate storage after both depletion treatments (8.44 mumol X g-1 X 2 h-1). In the liver, following 2 h of recovery, the rates of glycogen storage were similar after either glucose or fructose ingestion, but fasting caused a greater rate of repletion (83 mumol X g-1 X 2 h-1) than exercise (50 mumol X g-1 X 2 h-1). After 4 h of recovery fructose-fed exercised animals had the highest glycogen concentration (165 mumol X g-1) followed by the glucose-fed exercised group (119 mumol X g-1). These values were 50 and 36%, respectively, of that measured in the normal-fed liver (327 mumol X g-1). In contrast, liver glycogen values in the fasted group decreased between the 2nd and 4th hour of recovery in response to both feeding regimens. From these results we conclude that fructose is a poor nutritional precursor for rapid glycogen restoration in muscle after exercise, but that both glucose and fructose promote rapid accumulation of glycogen in the liver.

Ironman8
06-30-2003, 11:25 AM
If I consume complex carbs instead of simple carbs post-workout, would be still restore my muscle glycogen as effectively?

Maki Riddington
06-30-2003, 11:29 AM
Yes.

bradley
06-30-2003, 01:51 PM
Originally posted by Maki Riddington
*** Why consume fructose when glucose will do the job?


Would liver glycogen be replenished by the same amount if one were to consume only glucose as opposed to a combination of glucose and fructose, assuming same amount of glucose and fructose were consumed?

I am not disputing the fact that glucose can refill liver glycogen.

NPursuit
06-30-2003, 02:04 PM
Originally posted by Ironman8
If I consume complex carbs instead of simple carbs post-workout, would be still restore my muscle glycogen as effectively?

Yes and it's a healthier choice.

Holto
06-30-2003, 02:24 PM
how is is healthier?

Ironman8
06-30-2003, 03:29 PM
Originally posted by NPursuit


Yes and it's a healthier choice.

:withstupi

Please elaborate.

Maki Riddington
06-30-2003, 07:00 PM
Originally posted by bradley


Would liver glycogen be replenished by the same amount if one were to consume only glucose as opposed to a combination of glucose and fructose, assuming same amount of glucose and fructose were consumed?


*** Would it make a noticeable difference if I decided to forgo the fructose and simply use glucose?

Holto
06-30-2003, 07:34 PM
I'm sure you want Bradleys opinion but it seems our liver is pretty authoritative about these things and can absorb all it wants from the circulation

bradley
07-01-2003, 03:27 AM
Originally posted by Maki Riddington


*** Would it make a noticeable difference if I decided to forgo the fructose and simply use glucose?

What I am saying is that glucose preferentially goes to muscle glycogen, where as fructose will go to liver glycogen. By including both of these in your post workout shake you would be assuring that both the liver and muscle glycogen were being refilled.

I believe that by including fructose in your post workout shake you will be refilling liver glycogen faster than by consuming glucose alone, which would cause you to reach an anabolic state faster.

Maki Riddington
07-01-2003, 10:02 AM
Originally posted by bradley


What I am saying is that glucose preferentially goes to muscle glycogen, where as fructose will go to liver glycogen. By including both of these in your post workout shake you would be assuring that both the liver and muscle glycogen were being refilled.

I believe that by including fructose in your post workout shake you will be refilling liver glycogen faster than by consuming glucose alone, which would cause you to reach an anabolic state faster.

*** Although what you may believe appears to be sound in 'theory' I do not believe that using fructose post workout will make a world of difference in establishing an anabolic enviroment.

As I have pointed out, glucose gets the job done. Of course it doesn't hurt if you decide to throw a little fructose into the mix.