essensen skrev:En kombination af begge er ganske optimalt Dr. John Berardi påpeger de begge har fordele, og det er derfor nærliggende at blande det.

J-S-O skrev:

essensen skrev:En kombination af begge er ganske optimalt Dr. John Berardi påpeger de begge har fordele, og det er derfor nærliggende at blande det.

Må man høre et uddybende svar; eventult link til den pågældende artikel? Jeg har nemlig aldrig helt fået svar på hvorfor man burde blande de to kulhydrater udover at forsøg har vist at fruktose bliver optaget hurtigere sammen med et andet kulhydrat fremfor at blive indtaget alene; men det kan man selvfølgelig ikke bare overføre på druesukker og maltodextrin!

Next, I'd like to illustrate the differences between popular liquid carbohydrates including maltodextrin, dextrose, fructose, and sucrose.
Maltodextrin is a glucose polymer (a string of glucose units put together, similar to the protein peptide). It is therefore, by definition, a complex carbohydrate. However it's more complex nature does NOT slow digestion. Therefore, the GI and II remain high. Maltodextrin is the absolute best carbohydrate to consume during exercise for rapidly delivering blood glucose and for muscle glycogen recovery. It's also best for fluid uptake.
Dextrose (glucose) is a simple carbohydrate unit (similar to the amino acid). While it's good for exercise situations (malto is better), you're probably better off adding some dextrose to your maltodextrin formula. A little bit of dextrose may enhance the already excellent fluid uptake that occurs with maltodextrin during exercise.
Fructose is a simple carbohydrate unit, but it's structurally different from glucose. Due to its structure, it can possibly cause GI problems and/or decrease fluid uptake with exercise. Fructose, unlike other simple carbs, has to be "treated" in the liver and it reaches the muscle slowly.
Finally, sucrose consists of glucose and fructose units bonded together. Therefore, upon digestion, you get glucose and fructose in the GI (and the benefits and consequences of each).
Based on the three studies I reviewed (Blom et al 1987, ven Den Burgh et al 1996, Piehl et al 2000), it appears that dextrose is 72% faster than fructose for muscle glycogen resynthesis . As a result, at the end of 8 hours, muscle glycogen was 30% higher with dextrose ingestion. However, in another study, at the end of 4 hours, muscle glycogen was 15% higher with maltodextrin ingestion vs. dextrose. So dextrose kicks fructose's butt although malto beats up on dextrose.

Smeden skrev:Men det forklarer jo ikke hvorfor der er en fordel i at kombinere maltodextrin og glukose.

Dextrose (glucose) is a simple carbohydrate unit (similar to the amino acid). While it's good for exercise situations (malto is better), you're probably better off adding some dextrose to your maltodextrin formula. A little bit of dextrose may enhance the already excellent fluid uptake that occurs with maltodextrin during exercise.

Smeden skrev:Men det forklarer jo ikke hvorfor der er en fordel i at kombinere maltodextrin og glukose.

J-S-O skrev:

Smeden skrev:Men det forklarer jo ikke hvorfor der er en fordel i at kombinere maltodextrin og glukose.

Dejligt at høre, at jeg ikke er ene om forundrelse over forslaget! Det eneste forklaring jeg har hørt, er den du finder mest logisk; altså at maltodextrin betragtes som en partikel, men er et polysaccarid!

essensen skrev:

J-S-O skrev:

Smeden skrev:Men det forklarer jo ikke hvorfor der er en fordel i at kombinere maltodextrin og glukose.

Dejligt at høre, at jeg ikke er ene om forundrelse over forslaget! Det eneste forklaring jeg har hørt, er den du finder mest logisk; altså at maltodextrin betragtes som en partikel, men er et polysaccarid!

Tjaa - begge ting er jo gode at indtage efter træning - og har Berardi ret i sin antagelse, kan det vel på ingen måde skade at blande det - tværtimod (:

you're probably better off adding some dextrose to your maltodextrin formula. A little bit of dextrose may enhance the already excellent fluid uptake that occurs with maltodextrin during exercise.

essensen skrev:Det har jeg jo skrevet - Berardis antagelse:

you're probably better off adding some dextrose to your maltodextrin formula. A little bit of dextrose may enhance the already excellent fluid uptake that occurs with maltodextrin during exercise.

Og jeg fastslår lige - hvis han har ret i sin antagelse er der jo en lille fordel i at blande de to ting (: Jeg ved godt det ikke forklarer noget som helst - men hvis du vil have en grund til jeg blander de to ting, har du den der!

J-S-O skrev:

essensen skrev:Det har jeg jo skrevet - Berardis antagelse:

you're probably better off adding some dextrose to your maltodextrin formula. A little bit of dextrose may enhance the already excellent fluid uptake that occurs with maltodextrin during exercise.

Og jeg fastslår lige - hvis han har ret i sin antagelse er der jo en lille fordel i at blande de to ting (: Jeg ved godt det ikke forklarer noget som helst - men hvis du vil have en grund til jeg blander de to ting, har du den der!

Ja, problemet er bare at denne antagelse er baseret på undersøgelser der bygger på at fruktose optages hurtigere, hvis man kombinerer det med en anden type kulhydrat, fremfor at indtage det alene! Man kan ikke bare overføre dette resultat på andre kulhydrater, og sige at det samme må være gældende for dem; det er netop den problematik jeg gerne vil fremhæve! Men du har ret i, at den almene mening, er at man bør blande de to kulhydrater (glukose og maltodextrin)

From ABCBodybuilding:

Importance of consuming a combination of Maltodextrin & Dextrose


After reading Old School’s excellent article on post workout nutrition, the reader is now aware of the importance of consuming easily digested, high Gl carbohydrates at this time. But the question is, why a combination of dextrose and maltodextrin? Both are high in Gl rating, and easily digested right? True, but there is more logic than Gl rating to stacking these two powerhouses. Read on for the answer.

Beginning with the first concept discussed called, “gastric emptying.” Our goal post workout is to maintain a prompt digestion rate so nutrients can transport swiftly and efficiently to our muscles. With that said, it has been shown that this process slows when the ingested fluid contains a high osmolarity concentration (the second concept studied). Osmolarity is dependent on the number of particles in a solution. That is, a100-milliliter solution with 20 glucose molecules will have a higher osmolarity then a100-millileter solution that only contains 10 molecules. The shorter chain length a carbohydrate has, the higher it raises the solution's osmolarity. Therefore, it is no surprise that a pure glucose solution (or dextrose, a monosaccharide) induces very high concentrations of solute (1,3,10).

Fortunately these negative effects become greatly reduced when the drink contains a glucose polymer stacked with dextrose. However, a carbohydrate that is easily digested, and has a high Gl is still desired. Hence, a combination of dextrose and maltodextrin is advised. Osmolarity will be decreased, and glucose will still enter the blood stream at a proficient rate, thus maintaining its anabolic nature (1,3).

A second factor concerning osmolarity must now be examined. From a clinical standpoint, it is vital to take into consideration the fact that plasma (the liquid portion of blood) has an Osmolarity of 300 mOsm. This means that if one were to inject a solution with a greater concentration of solute into their blood, it would cause water from inside their red blood cells to leave by Osmosis (water always travels down its concentration gradient) and move into the plasma, in turn shrinking the erythrocytes (red blood cells). This is because the cells are iso-osmotic to the plasma (both have the same concentration of solute) (11).

A similar concept can be applied to your post workout meal. If a competitor were to consume a solution that was hypertonic or had a higher concentration of solute then 300 mOsm, it could dehydrate them (showing why digestion is rightfully slowed in a high concentrated solution). The addition of maltodextrin once again solves this problem (2,13).

The next question is, why not just use maltodextrin, and eliminate dextrose since it is so proficient? Ah, once again it is not that simple. Shi. X et al. in an outstanding study, tested the digestive effects of two substrates (any substance acted upon by an enzyme) as opposed to only one substrate in the small intestine. What they found was quite fascinating. The solution containing two substrates stimulated the activation of more transport mechanisms in the intestinal lumen, than did its singular counterpart. Therefore, more carbohydrates were transported out of the small intestine (absorbed into the blood), which additionally aided a greater absorption rate of water into the blood stream (by osmosis). Thus, the higher activation rate of transport mechanisms, even with higher osmolarity facilitated faster energy uptake and hydration (12)!