Revision as of 12:43, 13 March 2014

Maltodextrin is quickly absorbed type of carbohydrate that is used in many sports drinks and gels. It is made up of a chain of 3 to 19 glucose molecules, and so it is sometimes called a 'glucose polymer'. Maltodextrin is a fine white powder that dissolves well in water, though it does tend to form clumps if not mixed quickly. Maltodextrin is almost tasteless, with no real sweetness. Because Maltodextrin is easily digested and quickly absorbed into the blood stream, the Glycemic Index of Maltodextrin is higher even than glucose (105 – 136). Maltodextrin is isotonic at 150g (600 Calories)/16 oz or 9g/oz^[1], meaning you can put a lot of it into a drink and it will still be digested quickly. Maltodextrin can be purchased cheaply in bulk, with a 50 pound bag costing around $60 from Honeyville Grain. While Maltodextrin is technically a 'complex carbohydrate', the term is a little misleading in this context as Maltodextrin is more quickly digested and absorbed than simple carbohydrates (sugars).

1 When do you want Maltodextrin?

Based on Nutrient Timing, it's better to have a quickly absorbed carbohydrate during and immediately after exercise. For most people, the Maltodextrin will not cause a sharp rise in blood sugar during exercise as the muscles will absorb and use the extra carbohydrate. However, when you're not exercising or immediately after exercise you generally want to have slower carbohydrates (those with a lower Glycemic Index). Because Pasta generally has a low Glycemic Index, it has a well-earned reputation for being a good way of restocking your carbohydrate reserves (Glycogen).

2 Vitargo

Vitargo is claimed by the maker to be "The best carbohydrate in the world", but there is not the evidence to support this claim. Vitargo is similar to Maltodextrin, but has a longer chain length and is made from potatoes. The science behind Vitargo is rather limited and I don't find it particularly compelling. There are three published studies that compare Vitargo with "Glucidex IT 38", a mixture 15% glucose, 13% sugar and 72% Maltodextrin. The comparison with Glucidex seems rather strange, as comparison with Maltodextrin or a sport drink would be rather more appropriate.

• Improved stomach emptying^[2]. This study shows faster stomach emptying with Vitargo than Glucidex. Over an hour, that's 486ml rather than 369ml, or a 32% improvement, and the first 10 minutes showed more than double the emptying rate. However, there was no difference in blood glucose or insulin levels. The difference in emptying rate could be down to the additional sugars in the Glucidex.
• Glycogen resynthesis^[3]. This study showed that glycogen replenishment is faster in the first 2 hours, then slower in the subsequent 2 hours. Total glycogen replenishment over the full four hours was greater for Vitargo, though not statistically significant. The protocol used 300 calories every 30 minutes for a total of 1,200 calories, more than I suspect athletes would normally consume. The exercise consisted of 60 minutes running, 60 minutes cycling, and then cycling sprints to exhaustion.
• Improved performance^[4]. This study showed a 10% greater performance with Vitargo than Glucidex, which is remarkable. However, the study is carefully constructed to optimize the benefits seen in the early studies. The subjects exercised to exhaustion, took Glucidex or Vitargo, recovered for 2 hours and then did a 15 minute time trial. It's hard to see that situation being replicated in the real world.

From the evidence, it's hard to see Vitargo being worth the cost, though that would obviously depend on the individual. If you have to run a competitive 5K exactly two hours after a marathon, then it could be useful. On the other hand, Maltodextrin is about $1/pound, so Vitargo is way more expensive. Note that these studies use Vitargo, not Vitargo S2 which is made from Barley rather than Potato. Vitargo S2 is about $10/pound on Amazon.com.

3 Generation UCAN SuperStarch

Generation UCAN has a product called 'SuperStarch' that like Vitargo is a higher molecular weight carbohydrate. However, unlike Vitargo which is absorbed slightly more quickly than Maltodextrin, SuperStarch is absorbed more slowly.

3.1 What is SuperStarch?

SuperStarch is hydrothermally modified waxy maize that was developed for treatment of Glycogen Storage Disease, and for Diabetics. There are other forms of Waxy Maize, but it appears that SuperStarch may be different enough for them to be considered separately.

3.2 Should you use SuperStarch?

The idea of SuperStarch is that it does not lead to a rapid rise in blood sugar, but this is typically not a problem when exercising as your muscles use the extra carbohydrate. SuperStarch might be of use when restocking your glycogen at other times, but typically food based slow carbohydrates will contain other nutrients. It's possible that SuperStarch may be of use if you are training so hard that you cannot get sufficient carbohydrates from food sources, or for Carbohydrate Loading before a race. However, there is little evidence to support this.

3.3 SuperStarch and Exercise

So what's the effect on exercise? I could only find one study on SuperStarch and it showed no difference in exercise performance^[5]. This study compared Maltodextrin with SuperStarch and showed higher blood glucose at rest with Maltodextrin than SuperStarch, which is what you'd expect and is why you don't want a fast absorbed carbohydrate when at rest. However there was no difference in blood sugar levels during exercise, which again is what I'd expect. Here are some more details:

• The protocol was to take 1 g/Kg body weight of Maltodextrin or SuperStarch 30 minutes before exercise. The subjects then cycled at 70% V̇O₂peak for 150 minutes, then raised the intensity to 100% V̇O₂peak until exhaustion. They then took another 1 g/Kg and were monitored for 90 minutes of recovery.
• The Maltodextrin produced higher blood glucose before exercise, but then similar until the recovery period. During recovery, the Maltodextrin again produced higher blood glucose than SuperStarch.
• The SuperStarch had higher levels of blood Non-Esterified Fatty Acid (NEFA) than Maltodextrin, but there was no significant difference in carbohydrate or fat metabolism.
  • The study notes that the SuperStarch did produce a non-significant increase in fat metabolism towards the end of the exercise as measured by Respiratory Exchange Ratio. (0.92 v 0.95, p=0.07).
  • The Generation UCAN web site claims that SuperStarch increases fat oxidation based on the raise in NEFA, but the study clearly states that fat oxidation is not increased.
• During exercise, the Heart Rate was slightly higher with Maltodextrin; 154 rather than 150.
• There was no significant difference in actual performance, with exhaustion occurring after similar times with Maltodextrin and SuperStarch.

4 Waxy Maize

• Waxy Maize has been shown to be digested more slowly than a Maltodextrin/Sucrose mixture, producing a lower rise in blood glucose and insulin, but there was no change in appetite^[6].
• A study that compared Waxy starch (WS) to glucose (GL), resistant starch (RS) and a placebo (P)^[7]:
  • The study gave 1 g/Kg 30 minutes prior to 90 minutes of cycling at 66% V̇O₂max, then a 30 minute time trial.
  • At rest glucose produced a greater increase in blood glucose and insulin than the other conditions. However, during exercise blood glucose and insulin were similar between conditions.
  • Carbohydrate oxidation was lower in the placebo condition compared with all others.
  • Subjects performed better with glucose or waxy starch than the placebo.

5 Comparison of Carbohydrates

6 References

1. ↑ Nutrition of Maltodextrin (pdf of slides) http://www.arniebakercycling.com/pubs/Free/Nutrition%20Maltodextrin%20SS.pdf
2. ↑ JB. Leiper, KP. Aulin, K. Söderlund, Improved gastric emptying rate in humans of a unique glucose polymer with gel-forming properties., Scand J Gastroenterol, volume 35, issue 11, pages 1143-9, Nov 2000, PMID 11145284
3. ↑ K. Piehl Aulin, K. Söderlund, E. Hultman, Muscle glycogen resynthesis rate in humans after supplementation of drinks containing carbohydrates with low and high molecular masses., Eur J Appl Physiol, volume 81, issue 4, pages 346-51, Mar 2000, PMID 10664095
4. ↑ FB. Stephens, M. Roig, G. Armstrong, PL. Greenhaff, Post-exercise ingestion of a unique, high molecular weight glucose polymer solution improves performance during a subsequent bout of cycling exercise., J Sports Sci, volume 26, issue 2, pages 149-54, Jan 2008, doi 10.1080/02640410701361548, PMID 17852670
5. ↑ MD. Roberts, C. Lockwood, VJ. Dalbo, J. Volek, CM. Kerksick, Ingestion of a high-molecular-weight hydrothermally modified waxy maize starch alters metabolic responses to prolonged exercise in trained cyclists., Nutrition, volume 27, issue 6, pages 659-65, Jun 2011, doi 10.1016/j.nut.2010.07.008, PMID 20951003
6. ↑ AL. Sands, HJ. Leidy, BR. Hamaker, P. Maguire, WW. Campbell, Consumption of the slow-digesting waxy maize starch leads to blunted plasma glucose and insulin response but does not influence energy expenditure or appetite in humans., Nutr Res, volume 29, issue 6, pages 383-90, Jun 2009, doi 10.1016/j.nutres.2009.05.009, PMID 19628104
7. ↑ AC. Jozsi, TA. Trappe, RD. Starling, B. Goodpaster, SW. Trappe, WJ. Fink, DL. Costill, The influence of starch structure on glycogen resynthesis and subsequent cycling performance., Int J Sports Med, volume 17, issue 5, pages 373-8, Jul 1996, doi 10.1055/s-2007-972863, PMID 8858410
8. ↑ Y. Rong, M. Sillick, C.M. Gregson, Determination of Dextrose Equivalent Value and Number Average Molecular Weight of Maltodextrin by Osmometry, Journal of Food Science, volume 74, issue 1, 2009, pages C33–C40, ISSN 00221147, doi 10.1111/j.1750-3841.2008.00993.x