Sip it or Gulp it?

Gulp it

If you have been exercising continuously for over an hour, you know that you have to refuel at some point. Especially if you are participating in a race. Carbohydrate refuelling during a race or a long training session can definitely enhance your exercise performance since there is a limited store of glycogen (carbohydrates) in your liver.

Sip it

The amount of carbohydrates (carbs) in the stomach is one of the main factors that would determine the speed of gastric emptying. A larger volume will empty faster than a smaller volume.*

However, a large volume of carbs in the stomach is not ideal for runners. How many of you runners reading this can drink large volumes of fluid (or eat lots of energy gels) during races and endure the fluids sloshing around in your stomach and intestines? 

When I was still competing in triathlons, I always took small sips while running past the feed stations. I would mostly eat/ drink on the bike leg of the triathlon as it does tend to sit better in my stomach since there is less movement while I'm cycling. 

However, a study I read studied whether ingesting carohydrate sports drinks during prolonged running affects exogenous carbohydrate oxidation (sparing liver glycogen, and yet maintain exercise intensity)  and gastrointestinal discomfort. This means that your glycogen stores are not being used as quickly during exercise since whatever you are drinking is being used to fuel your exercise.

The runners studied did two, 100 minutes of steady state runs at moderate intensity. In the first run, the runners consumed 200mL every 20 min while they took 50 mL every 5 min during the second run.

The researchers found that exogenous carbohydrate oxidation rates were 23 percent higher during exercise when larger volumes were ingested every 20 minutes. They concluded that ingesting larger volumes would be better than frequently sipping small amounts since large volumes will stimulate gastric emptying and makes more carbs available for intestinal absorption.

More importantly, there was no difference in gastrointestinal problems whether a larger or smaller amount was ingested while running. The authors indicated that this was also similar to what was observed in earlier studies. They suggested that runners may be able to tolerate more fluids than they think they can during exercise.

Those who are still competing should try and practice ingesting more carhohydrate gels/ drinks in training to make sure you do not get any stomach upsets. This will train your gut to absorb more carbs and help you race faster.

Reference

Mears SA, Boxer B, Sheldon D et al (2020). Sports Drink Intake Pattern Affects Exogenous Carbohydrate Oxidation During Running. Med Sci Sports Ex. 52(9): 1976-1982. DOI: 10.1249/MSS.0000000000002334

*This topic has been well studied and recommendations are to consume 30-60 g/hr for exercise/ events lasting between 1 to 2.5 hours. For exercise/ events over 2.5 hours, up to 90g/ hr should be consumed. If more than 60g/ hr needs to be ingested, a combination of carbohydrates (e.g. glucose and fructose) needs to be ingested. 

Here's how I fold the paper cup to sip while running