Timing & Dosage

Some of the most common questions asked by athletes is ‘When should I take the first gel during my X event (X being marathon, triathlon, adventure race, etc)’? Followed by… ‘How often should I be taking gels during the event’? The answers depend primarily on the duration of exercise, but are also affected by intensity and whether you’re starting the event in a fed or fasted state. A brief outline is shown in Table 6.

 

 

Table 6. Recommended Gel Intake

Exercise Duration	Event Example	Fed State	Fasted State
< 45 minutes	5K/10K Race	No gels needed	1 gel 15-30 min pre-event
45-75 minutes	Sprint Triathlon	Mouth rinse of CHO at halfway point (small squirt of gel or sip of sports drink)	1 gel 15-30 min pre-event; mouth rinse of CHO at halfway point (small squirt of gel or sip of sports drink)
1-2 hours	Half Marathon	1 gel at the 1 hr mark	1 gel 15-30 min pre-event; 1 gel at the 1 hr mark
2-3 hours	Olympic Distance Triathlon	1-2 gels per hour starting at the 1 hr mark (Up to 60g CHO/hr)	Pre-event meal or 1-2 gels 15-30 min prior to start; 1-2 gels per hour starting at the 1 hr mark during event. (Up to 60g CHO/hr)
3+ hours	Marathon+, Ironman Distance Triathlon+, Half Century+, Adventure Race	2-3 gels per hour starting at the 1 hr mark (60-90g CHO/hr)	Pre-event meal or 2 gels 15-30 prior to start; 2-3 gels per hour starting at the 1 hr mark during event. (60-90g of CHO/hr)

 

*This table relies on the assumption that most competitions have early morning start times. In the case of an afternoon or evening competition, most athletes consume one or two meals during the day, so the ‘Fasted State’ column can largely be ignored.

Fed state = breakfast or other meal prior to event

Fasted state=no breakfast/meal or very small amount of calories consumed prior to event

Here's a link to an article showing a detailed energy gel plan for a Half Marathon.

 

Some athletes don’t like to eat a lot before their race due to stomach issues, particularly with events that take place early in the morning. For this reason, two columns of ‘Recommended Gel Intake’ are shown in Table 6 to address being in a fed or fasted state. The human body stores carbohydrate in a molecule called glycogen, which can be quickly broken down into glucose for energy. Glycogen is stored in your muscles and liver and although muscle glycogen stores change very little overnight as you sleep, liver glycogen can be depleted by as much as 50%. Eating breakfast helps to restore liver glycogen levels so that your energy reserves are topped off prior to the beginning of competition. Skipping out on breakfast however, puts you at the starting line in a fasted state, which means you’ll need to consume a quickly digestible carbohydrate either immediately before or during the event to make up for your depleted liver glycogen.

Recent studies have shown that doing a simple carbohydrate mouth rinse (sloshing some sport drink around in your mouth and then spitting it out) is all that is needed to improve endurance performance in high intensity short duration exercise (lasting <75 minutes). It is thought that carbohydrate receptors in the mouth (previously unknown) are essentially relaying a message to the brain that ‘fuel is coming’, which enables the athlete to push a little harder and faster. For prolonged exercise (2+ hours), it’s well known that carbohydrate should be ingested during exercise to benefit performance. Use Table 6 above as a general guideline and tweak it to best fit your personal needs.

One last note: Obviously, a pre-event meal becomes more important the longer the race duration. For example, if I have a 10K race first thing in the morning I tend to opt for a very light breakfast (granola bar or ½ bagel) or 1 gel prior to the race start, whereas if I know I’m going to be out there for more than 2 hours I make a point to get in a decent sized meal.