By Dr. Luke Bucci, PhD
Discover how your body turns every carb source into glucose in order to generate ATP and power muscles. Also learn why increasing ATP production is much (much!) more complicated than simply gobbling up glucose.
One of the most frequent questions we get is how much carbs do I need to take (or, often, how much can I take) during my long-duration events, races, or training? This blog is a follow-up to the previous blog about increasing carbs/hour during endurance exercise, where Dr. Bucci answered that question. One thing he didn’t cover in that last blog is that, with higher carb intake, timing is everything, so in this blog, Dr. Bucci addresses when to go big on carbs.
One of the most frequent questions we get is: How many carbs do I need to take during my long-duration events, races or training lasting more than three hours? The prevailing wisdom has long been set at 30-60 grams per hour (120-240 calories/hour), and usage directions for EFS & EFS-PRO are based on this time-tested range. But emerging research suggests athletes can ingest more and more carbs per hour: 90-140 grams or 360-560 Calories. That’s 1.5 to 19 times MORE carbs than the endurance experts have agreed upon for years!
The Glycemic Index (GI) is a characteristic of carbs in different foodstuffs that affects choosing what carbs to use during long-term exercise. Since glucose is by far the main sugar in the bloodstream, glycemic index tracks the change in blood glucose levels for 4-6 hours after eating on an empty stomach, and it’s measured by administering 100 grams (about a quarter pound) dry weight of a specific carb source. The area under the curve for the rise in blood sugar from 100 grams of glucose is defined as a GI = 100.