Why Eat before a workout

The main goal of eating before a workout is to replenish your glycogen, the short-term storage form of carbohydrate.
Glycogen supplies immediate energy needs and is especially crucial for morning workouts, as the liver is glycogen depleted from fuelling the nervous system during sleep. The muscles, on the other hand, should be glycogen-loaded from proper recovery nutrition the previous day if you hit the post workout routine right. 

The body does not necessarily need a lot (depending on the timing and type of session), but it does need something to prime the metabolism, provide a direct energy source, and allow you to perform the session at the planned intensity and for the given 

As for what the something is, following the basic guidelines it is best to experiment with a few different snack and meal choices and see which works best for you. 

What to Eat Before a Workout

As stated above, this will come down to personal preference. 

The majority of nutrients in a pre workout meal should come from carbohydrates. You also need some protein, but not a significant amount as protein takes longer to digest and does not serve an immediate need at the beginning of your workout. Fat and dietary fibre also should be marginal to minimise the potential for gastrointestinal upset – we’ve all been there right! 

Research has shown that the type of carbohydrate consumed does not directly affect performance across the board. Some thrive on regular foods (e.g., my personal favourite; a bagel with peanut butter). Some reach for the convenience options such as an energy bars or replacement shakes.

One crucial element that is often overlooked is Pre-workout fluid intake. This is critical to prevent dehydration, which results in a severe drop in performance as best and serious help issues at worst. Be sure to time your fluid intake so that you are not busting for the loo during your workout. Ideally start 4 hours before and aim for 5-7mls per kilo of bodyweight. 

When to Eat Before a Workout

When is a huge consideration for pre workout nutrition and almost as important as what. 

Eat too early and the calories are gone by the time the exercise begins. Eat too late and the stomach is stealing all your energy trying to do its digestion thing, and making you feel uncomfortable in the process. 

As a general rule the ideal time for most people to eat is about 2-4 hours before activity. Again, you can play with this depending on the session/day you have and figure out in different situations, what works best. 

If your meal time is 4 hours before your workout you can safely consume up to 1,000 calories. If the gaps between eating and training are much shorter (a pre-7 a.m. workout, for example), eating a smaller meal of around 300-400 calories or less, about an hour before the workout, can suffice.

A general recommendation that can be a good jumping off point to figure out what works for you is to consume about 1 gram of carbohydrate per kilogram of body weight if working out 1 hour after eating, 2 g of carbohydrate per kg of body weight if working out 2 hours after eating… and so on. 

To avoid GI issues it is advised that anything consumed less than 1 hour before an event or workout be in liquid form, such as a sports drink or smoothie.

Get it Right

An effective pre workout nutrition plan should be planned based on the duration and intensity of session. You should also take into consideration your ability to supplement during the activity (if longer than 45-60 minutes), your personal energy needs and environmental factors; is it hot, humid, cold etc.

Determining how much is too much or too little and getting the timing right can be frustrating, but experimenting is vital for success.