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Post-Workout Simple Carbs Necessary?

So, I’m just starting to really learn the science behind our body’s metabolism and how it utilizes food. I was thinking the other day, is eating a post-workout ( That hour window of opportunity) meal really that important? I mean, as long as you still get in enough calories throughout the day, does that post-workout window really matter all that much?

The argument against not eating after is that your muscles are glycogen-depleted and all this, so you’d want to ingest simple carbs to quickly replenish glycogen stores…but wouldn’t most people not on a low-carb diet be very rarely glycogen depleted? I mean it takes people a few days to go into a state of ketosis, so doesn’t that fly in the face of the assumption that you’d be glycogen-depleted after only a 1-1.5 hour workout?

I’m just thinking, your body can also use fat stores and convert it to glycogen, so someone with a fair amount of body fat (10+%) would have plenty of “stored energy” to convert to glycogen. Kind of like the argument that people who are fairly lean shouldn’t do HIIT too much because they don’t have that much “stored energy” and their body could tap into protein stores for energy…

Diet’s the one aspect of bodybuilding that I think is the most variable and individualized, I realize this, but what do you think?

For the record, I’m getting in enough calories, I’m tracking my diet on fitday.com, and I just finished working out and I’m eating my post-workout sandwich but I’m still thinking about this subject.

Feedback?

Your thinking is correct IMO. I don’t know about fat stores being converted into glycogen argument, but I agree with everything else.

I’ve seen many studies to suggest that the “PWO window” is much longer than the 1 hour people would like you to believe and could be as wide as 36 hours. Overall, total daily nutrition/macros are MUCH more important. So much so, its almost not worth fussing about PWO perfection.

Fat won’t convert to glycogen.

Muscle can be broken down and converted into glycogen, but not fat.

[quote]elusive wrote:
Your thinking is correct IMO. I don’t know about fat stores being converted into glycogen argument, but I agree with everything else.

I’ve seen many studies to suggest that the “PWO window” is much longer than the 1 hour people would like you to believe and could be as wide as 36 hours. Overall, total daily nutrition/macros are MUCH more important. So much so, its almost not worth fussing about PWO perfection.[/quote]

I was thinking the same thing, the value of eating in that window though could be seen as beneficial because it gets you in another meal, and another source of calories, in on the day that you wouldn’t have had before.

But if throughout the day, you still get in enough calories then it could be seen as less important.

Good stuff.

[quote]jehovasfitness wrote:
Fat won’t convert to glycogen.

Muscle can be broken down and converted into glycogen, but not fat.[/quote]

Fat can’t be converted into glucose?

I have my peri/post workout shake with some simple carbs in it…and then my PWO meal is either cheerios or eggs (depending on the day)

your thinking is on track w/ my thoughts before I started my C2L diet a few months back.

I used to not use a post workout shake or meal and it took me forever to gain weight and strength. After I started supplementing with them it was like the missing piece to the puzzle, and everything just clicked.

I know it works for me so I will continue to do it.

Its my understanding that most fat oxidation will result in ketones for the body to use. Any gluconeogenesis that creates new glucose will be used primarily by cells (red blood cells ect) and is usually created by lactic acid, glycerol and certain amino’s. Even with the creation of new glucose, it is not a optimal (not even close) way to replenish glycogen.

[quote]That One Guy wrote:
jehovasfitness wrote:
Fat won’t convert to glycogen.

Muscle can be broken down and converted into glycogen, but not fat.

Fat can’t be converted into glucose?[/quote]

Nope… "Oxidation of fatty acids yields enormous amounts of energy on a molar basis, however, the carbons of the fatty acids cannot be utilized for net synthesis of glucose. The two carbon unit of acetyl-CoA derived from b-oxidation of fatty acids can be incorporated into the TCA cycle, however, during the TCA cycle two carbons are lost as CO2. Thus, explaining why fatty acids do not undergo net conversion to carbohydrate.

Training is catabolic in nature. During training, or any stress for that matter, cortisol is released. This is good during the workout as cortisol is the hormone that “breaks things down”. The problem is that if cortisol is left at a high level post-workout you will be breaking things down for a long time. This is why runners look like pencils with heads. Too much catabolic stress.

A spike in sugar we all know releases insulin. Insulin is the “build things up” hormone. Insulin is bad most of the time because in bulk it tells your body to store fat. BUT, if you are in a glycogen depleted state the insulin counteracts the cortisol. Insulin tells your body to “store glycogen”.

It’s not what you eat that matters but WHY and WHEN.

If you want your muscles to recover and grow you need an insulin spike post workout. To achieve this spike you need simple carbs such as fructose.

The window matters because after your workout is when your body is most insulin sensitive. If you wait then the sensitivity is less you won’t readily store those carbs as glycogen as much. Glycogen storage is not a fixed #.

The difference among bodybuilders, and all athletes, is the degree of sensitivity throughout the day. If you’ve been on a high carb diet you whole life you’ll be very insensitive and will readily store carbs as fat. If you’ve very sensitive you could need to consume mass quantities of sugar just to keep from losing muscle!

Alan

All right sounds good, well my understanding was that glucose stores could be replenished through fat oxidation but it seems I was mistaken.

Thanks Alan for that response regarding the insulin spike.

That was one point FOR not eating after a workout, because an insulin spike would stop HGH production, which would stop fat burning. But I hadn’t thought of the cortisol-stopping side effect.

I think the body’s ability to use lactic acid for fuel is really fascinating and should be exploited.

[quote]That One Guy wrote:
All right sounds good, well my understanding was that glucose stores could be replenished through fat oxidation but it seems I was mistaken.

Thanks Alan for that response regarding the insulin spike.

That was one point FOR not eating after a workout, because an insulin spike would stop HGH production, which would stop fat burning. But I hadn’t thought of the cortisol-stopping side effect.[/quote]

Yeah, this is why I find it important to keep protein levels higher on a diet (1.5 grams per pound of BW). This allows gluconeogenesis to occur from the protein that you eat from food rather than digging into your muscles to get the protein. Fat stores can supply energy for your daily activities, but hard training wants to use glucose.

[quote]PonceDeLeon wrote:
I think the body’s ability to use lactic acid for fuel is really fascinating and should be exploited.[/quote]

Hmm…so you’d be FOR delaying post-workout nutrition? At least in theory if not in practice.

Wait a minute here… Why delay PWO nutrition?

Also, just to bring some food for thought up. Chris Aceto (very successful BodyBuilding Prep Coach and intelligent individual) claims that cortisol is not the evil hormone people claim and that it is indeed actually very good for fatloss/overall body comp. If anyone is interested, you can look up his thoughts on the subject.

sometimes im blown away at the level of indepth knowledge attained by people on this site…

then im knocked off my feet at how ignorant some people are at the same time, theres always a few.

good posts guys, i swear i learn more on here than in uni :wink:

[quote]That One Guy wrote:
So, I’m just starting to really learn the science behind our body’s metabolism and how it utilizes food. I was thinking the other day, is eating a post-workout ( That hour window of opportunity) meal really that important? I mean, as long as you still get in enough calories throughout the day, does that post-workout window really matter all that much?

The argument against not eating after is that your muscles are glycogen-depleted and all this, so you’d want to ingest simple carbs to quickly replenish glycogen stores…but wouldn’t most people not on a low-carb diet be very rarely glycogen depleted? I mean it takes people a few days to go into a state of ketosis, so doesn’t that fly in the face of the assumption that you’d be glycogen-depleted after only a 1-1.5 hour workout?

I’m just thinking, your body can also use fat stores and convert it to glycogen, so someone with a fair amount of body fat (10+%) would have plenty of “stored energy” to convert to glycogen. Kind of like the argument that people who are fairly lean shouldn’t do HIIT too much because they don’t have that much “stored energy” and their body could tap into protein stores for energy…

Diet’s the one aspect of bodybuilding that I think is the most variable and individualized, I realize this, but what do you think?

For the record, I’m getting in enough calories, I’m tracking my diet on fitday.com, and I just finished working out and I’m eating my post-workout sandwich but I’m still thinking about this subject.

Feedback?

[/quote]

Thinking out loud here, for arguments’ sake:

If you’re saying that it takes a couple days to get to ketosis, which to me means that your body has adapted to using fat for fuel due to the chronic lack of glycogen and carbohydrates, then someone who ISN’T in a ketogenic state would rely exclusively on that stored glycogen for fuel. Thereby, after a glycogen depleting workout (Squating til you puke), your body would require more uptake immediately to get back to either homeostasis, or to repair itself beyond previous standards. So, I guess my theory there is that if you’re in ketosis, it’s not as big a deal (though I wouldn’t avoid it), but if you’re not on a low carb diet, it would be much more critical.

This article (I only read the abstract, got lazy) has some interesting findings
http://www3.interscience.wiley.com/journal/119076813/abstract?CRETRY=1&SRETRY=0

[quote]elusive wrote:
Wait a minute here… Why delay PWO nutrition?

[/quote]

No reason, just wasn’t sure what he was saying.

[quote]

Also, just to bring some food for thought up. Chris Aceto (very successful BodyBuilding Prep Coach and intelligent individual) claims that cortisol is not the evil hormone people claim and that it is indeed actually very good for fatloss/overall body comp. If anyone is interested, you can look up his thoughts on the subject.[/quote]

Yes, I looked around on him…It seems only recently has he been touting cortisol as a possible good thing…right around the time that he is releasing a new product. Maybe trying to get some attention? If anything, most of his writings so far, from what I could see, have been to minimize cortisol.

Hmmm… found this.

Interesting.

Yeah, I always thought of cortisol as the “break down” hormone, not only with respect to muscle tissue (obviously bad) but also fat tissue (good).

The sad thing is, if you’ve been reading articles long enough, you will notice a trend of authors parroting each other without questioning what was originally said.

[quote)That One Guy wrote:
Hmm…so you’d be FOR delaying post-workout nutrition? At least in theory if not in practice.
[/quote]

No. What I am saying is you can do lactate training (circuits, HIIT) but perhaps take a 5 min break, pop some BCAAs, then do SS cardio and have your body use the lactic acid built up as fuel, which it will do if you provide it with increased oxygen consumption (aerobic activity by way of SS cardio).

I am starting to believe the member who posted in the Alpha thread “Things you can’t prove” regarding fat intake prior to a fat loss workout. I think priming the body for mobilizing/storing fat, before a fat loss centric workout session, keeps the body focused on mobilizing fat stores and using them for fuel. I don’t know the science, though.