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Study: Caffeine Co-ingested with Carbs


"High rates of muscle glycogen resynthesis after exhaustive exercise when carbohydrate is coingested with caffeine."

We determined the effect of coingestion of caffeine (Caff) with carbohydrate (CHO) on rates of muscle glycogen resynthesis during recovery from exhaustive exercise in seven trained subjects who completed two experimental trials in a randomized, double-blind crossover design. The evening before an experiment subjects performed intermittent exhaustive cycling and then consumed a low-CHO meal. The next morning subjects rode until volitional fatigue. On completion of this ride subjects consumed either CHO [4 g/kg body mass (BM)] or the same amount of CHO + Caff (8 mg/kg BM) during 4 h of passive recovery. Muscle biopsies and blood samples were taken at regular intervals throughout recovery. Muscle glycogen levels were similar at exhaustion [ approximately 75 mmol/kg dry wt (dw)] and increased by a similar amount ( approximately 80%) after 1 h of recovery (133 +/- 37.8 vs. 149 +/- 48 mmol/kg dw for CHO and Caff, respectively). After 4 h of recovery Caff resulted in higher glycogen accumulation (313 +/- 69 vs. 234 +/- 50 mmol/kg dw, P < 0.001). Accordingly, the overall rate of resynthesis for the 4-h recovery period was 66% higher in Caff compared with CHO (57.7 +/- 18.5 vs. 38.0 +/- 7.7 mmol x kg dw(-1) x h(-1), P < 0.05). After 1 h of recovery plasma Caff levels had increased to 31 +/- 11 microM (P < 0.001) and at the end of the recovery reached 77 +/- 11 microM (P < 0.001) with Caff. Phosphorylation of CaMK(Thr286) was similar after exercise and after 1 h of recovery, but after 4 h CaMK(Thr286) phosphorylation was higher in Caff than CHO (P < 0.05). Phosphorylation of AMP-activated protein kinase (AMPK)(Thr172) and Akt(Ser473) was similar for both treatments at all time points.

We provide the first evidence that in trained subjects coingestion of large amounts of Caff (8 mg/kg BM) with CHO has an additive effect on rates of postexercise muscle glycogen accumulation compared with consumption of CHO alone.

Anyone seen this?

I take it that it could be a good strategy to be on something like ReceptorMax or R-ALA on carb-up days and to use the caffeine+CHO strategy for glycogen resynthesis during that time.

Any thoughts?


I saw it in a MuscularDevelopment mag a few months ago.

Occasionally I like to train really early in the A.M. and have some coffee with my pwo meal.

I like the thought and theory, I'll have to do more research but I remember seeing a flaw somewhere. Or that the positives reguarding the uptake of glycogen with caffiene were outweighed by the dose of caffiene you'd have to take and the sides that come with that.

I'll see if I can find the article.

I think it's worth a shot tho. I think that coming home, Grubbing, then passing out for an hr or two would do more good tho personally. I know many of us don't have the time for that.



Right, I agree that a dose of 8 mg / kg BW is pretty high. For me, that is about 600 mg of caffeine in one shot. If I am not well rested and hydrated that day, I risk getting jittery and possible heart palpitations. That's two cans of Spike Shooter in one shot. Again, if I were to even consider this, I would only use the strategy once every 7-10 days (assuming a carb cycling approach to diet) when I have a PWO, carb-up meal, along with something like R-ALA to maximize muscle glycogen uptake.

I am sure there is a lower dosage of caffeine that is still beneficial, but I also think there must be a point where such tricks aren't necessary, i.e. when your insulin sensitivity is already high enough to where the side effect of such a high dose of caffeine would not warrant the marginal benefit on glycogen resynthesis.

I just thought it was interesting and I am sure there are other compounds that can yield similar effects.


I am not sure if that is what is happening when the caffeine is given post workout, but Jen Heath gave a great article on FigureAthlete about this.

Basically, caffeine or adrenaline rising causes insulin resistance in all the tissues. However, as we know, resistance training and supplements like RECEPTORMAX increase insulin sensitivity in the muscles. So, you'd basically end up with insulin resistant fat cells and insulin sensitive muscles... the perfect time for a high-carb meal to resynthesize glycogen.

Again, I don't know if that it what is happening in the study, but I wouldn't be surprised if it was related.


Exactly. I'm not sure a little extra glycogen is worth seeing if 800mg of caffeine makes one of my eyeballs shoot out of my head.


I like the theory with the carb cycle approach.