When to eat Energy Gels in the Marathon

From Fellrnr.com, Running tips
Revision as of 17:45, 16 April 2013 by User:Fellrnr (User talk:Fellrnr | contribs)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search

It is not uncommon for Gels to be offered once or twice in the latter miles of a marathon, but is that the right time to eat them? Are one or two Gels the right number?

1 The Problem

The general recommendation is to consume 30-60g of carbohydrate per hour as 8-16 oz drink every 10-15 minutes for optimum performance[1]. More recent evidence on carbohydrate metabolism has shown that up to 60 grams of glucose/Maltodextrin plus 40 grams of Fructose can be absorbed and metabolized per hour. There are problems getting this from sports drink in a marathon…

  • Aid stations are not 10-15 minutes apart for most runners. If aid stations are 2 miles apart, then only the faster runners will move between them in under 15 minutes.
  • It's hard to consume 8-16 oz of drink at each aid station, as each cup provides only ~4 oz, and it's hard to drink it all rather than wear it when running.
  • Drinking 8-16 oz every 10-15 minutes under cool conditions can lead to the need to urinate, which impacts finishing time. I would not recommend this approach for hydration - see Practical Hydration.
  • I have rarely had a sports drink in a marathon that is well made up. Mostly it is too dilute, and occasionally very strong.

2 Carbohydrates from Gels

To get 30-60 grams of carbohydrate an hour from energy gels requires a gel packet every 30 minutes. This would be 8 gels in a four hour marathon, which is much higher than most people consume. There is evidence that this extra intake can not only improve performance, but also reduce muscle damage. (See Nutrient Timing for more details.) I know of some good marathon runners who practice this approach. One of them takes his first gel at mile 1, then every 5 miles after that, which works out as every 30 minutes at his marathon pace.

The guideline of a gel every 30 minutes will need adjustment for each athlete. Heavier athletes may need more and lighter may need less. Faster athletes may need more gels and slower athletes less.

3 Gels at the start

It may be worthwhile to consume a packet a couple of minutes before the start of the race. It is easy to consume a gel at this point, and the body can start to digest it while at relative rest.

4 Adding Protein

There is some evidence that adding protein to the carbohydrate can improve performance[2], as well as attenuate muscle damage in endurance exercise[3].

5 Caffeine in Gels

Caffeine not only improves performance, it also increases the absorption of sugar from the gut, so it will make Gels quicker acting.

6 The Golden Rule

It is vital to remember The Golden Rule of Racing and practice this in training. If you want to try energy gels with protein, you need to try these out at race pace.

7 See Also

8 References

  1. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2575187/ During exercise, CHO should be consumed at a rate of 30 – 60 grams of CHO/hour in a 6 – 8% CHO solution (8 – 16 fluid ounces) every 10 – 15 minutes.
  2. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2575187/ Adding PRO to create a CHO:PRO ratio of 3 – 4:1 may increase endurance performance and maximally promotes Glycogen re-synthesis during acute and subsequent bouts of endurance exercise
  3. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2575187/ The authors concluded that combined ingestion of PRO and CHO improves net PRO balance at rest, as well as during exercise and post-exercise recovery