Caffeine
As an athlete, there are a few things you should keep in mind regarding caffeine intake. Caffeine is consumed by many people on a daily basis, and most don’t give it a second thought while drinking multiple cups of coffee in the morning along with using caffeinated sports nutrition products during training at any time of the day. Caffeine affects some people more than others, but it has some effect on almost anyone who consumes it. It may take some trial and error to see how your body uniquely responds to caffeine, but I’ll go over some of the main things to think about.
The first thing to consider is whether you are a fast or slow metabolizer of caffeine. This is primarily genetically predetermined, but if you drink caffeine and the effect of alertness stays with you for a long time, the effect is minimally noticeable, or it disrupts your sleep at night (keeping you awake or waking up early), then you may be a slow metabolizer of caffeine. On the other hand, if you drink caffeine and notice a rapid increase in alertness that doesn’t stay with you long, and you have no problem drinking an afternoon cup of coffee without sleep issues, then you are likely a fast metabolizer.
A cup of coffee has about 100mg of caffeine, which is plenty to affect the stimulation of your nervous system. Caffeine increases your alertness and ramps up your body’s “fight or flight” response.
In normal cases, throughout the day you build up adenosine in your brain which binds to receptors and makes you feel tired. The way caffeine helps you stay alert is that it blocks adenosine from binding to its receptors in the brain.
Some good rules to follow regarding caffeine intake would be to limit morning coffee intake to less than 3mg/kg (3mg of caffeine per kilogram of body weight) or roughly 2 cups of coffee. Caffeine can have a diuretic effect when consumed in excess of 3-6mg/kg. Limiting your morning caffeine intake will also help metabolize the caffeine out of your system throughout the rest of the day so it does not interfere with your sleep. This brings me to my next point. Do not drink caffeine any time past 12:00pm (noon). Caffeine stays in the body for about 6 hours, but how long it stays in your system is different among individuals. Stopping caffeine ingestion at noon ensures that your body can remove it in time so that you can initiate an uninterrupted sleep rhythm.
If you are training in the afternoon, avoid taking caffeinated sports nutrition products for the same reason I mentioned before. Training at high intensity in the afternoon with caffeine ingestion would be a recipe for sleep disaster as high-intensity exercise already tends to keep you more alert and impact your sleep. While it is beneficial to test how you respond to caffeinated sports nutrition products in training, try to do those sessions in the morning and save your caffeine intake in the afternoon for race days.
When it comes to performance, caffeine is well known as an ergogenic aid (it improves performance). Caffeine is known to increase sympathetic activation therefore increasing heart rate, blood flow, and alertness. It is also helpful in lowering RPE during training and you may be surprised at how much your cup of coffee makes your training feel a little easier than it really is, and you won’t know this until you try to train without caffeine (assuming you consistently consume it).
If you stop drinking caffeine, you will likely notice withdrawal symptoms such as headache or abnormal sleepiness. If you are having trouble getting or staying asleep at night, it might be worth trying to stop drinking caffeine for a few days.
There is an idea around caffeine that in order to maximize its performance benefits of increased alertness and decreased RPE that you need to either be a non-habitual user or stop drinking caffeine for at least a month to eliminate any tolerance you may have built up. While caffeine may elicit a greater performance effect on race day to those without a caffeine tolerance, the potential negative effects of withdrawal far outweigh the benefits of abstaining for a month leading into your race. By being a habitual caffeine user, you are gaining a performance advantage on a daily basis, therefore you are getting more out of your sessions. The best strategy would be to continue your daily caffeine habits to help you execute high-quality and consistent training, then increase your dose on race day for a greater performance effect. The problem with abstaining for a month leading into a race in an attempt to have a greater effect on race day is that you will experience withdrawal symptoms that may interfere with your training quality and consistency.
SUMMARY:
Caffeine is an ergogenic aid that lowers RPE and increases alertness.
Limit coffee intake to less than two cups in the morning
If you are having trouble sleeping, limit your coffee intake to 0.5-1.0 cups of coffee in the morning
Avoid drinking caffeine after 12pm noon so it does not negatively impact your sleep, stopping earlier (such as 10am) will only further help your sleep
Avoid using caffeinated sports nutrition products when you are training in the afternoon. If you need to test caffeinated products in training before your race, do so in a morning session if you can. Obviously, if your race is in the afternoon, you will use caffeine
If you are having trouble sleeping at night, try lowering your caffeine intake to decrease your sleep latency and increase your sleep quality/quantity
You do not need to abstain from caffeine to maximize its benefits, rather maintain your caffeine habits and increase your dose slightly on race day for a greater effect
Disclaimer* I am only offering general nutrition advice and I highly recommend working with a registered dietician for more professional nutrition guidance. This is not intended to be medical advice to diagnose or treat diseases.