What to eat for each workout
In a typical week for most runners, there are 3 types of runs in your training plan:
- Easy/recovery runs and base line
- Long runs
- Strength or speed workouts, usually repeats, tempo runs or track sessions.
- Easy/recovery runs are at a comfortable, conversational pace and usually don’t last longer than 60 minutes. Base runs are the core of your workout plan
- Long runs vary by pace and are longer than 90 minutes.
- Strength and speed workouts are shorter in duration but higher in intensity than the other two types of runs.
Each type of run is associated with different fueling needs and different physiologic responses. So, you need to plan accordingly.
Reasons for having something to eat before a run
Liver glycogen, which maintains a normal level of blood sugar, can be depleted overnight. A small amount of food before exercise will increase your blood sugar and help prevent hypoglycemia, which could cause lightheadedness, blurred vision and fatigue.
Food also helps settle your stomach and absorb some of the stomach juices that can cause discomfort, especially if you haven’t eaten in a while.
Finally, a pre-exercise snack is a last chance to fuel your muscles. Food eaten far in advance of a workout will be stored as muscle glycogen, but food eaten in the hour before exercise can be used as instant fuel if the exercise intensity is low enough to still allow for digestion.
Possible reasons not to eat
It is a common belief that exercising on an empty stomach will enhance the body’s use of fat as a fuel source, allowing one to burn more body fat. While this is true, understand that burning body fat to fuel exercise does not necessarily mean that one will lose body fat overall.
To lose body fat, you still need to have an overall calorie deficit by the end of the day. If exercising on an empty stomach just sets you up to eat more later in the day than you would have if you ate before running, then there is no benefit.
Also, consider the fact that a small snack before may allow you to exercise harder and run longer, which would result in burning more calories.
Fears of getting an upset stomach, diarrhea, or just feeling sluggish are other reasons why one might choose not to eat before exercise. Avoiding foods that are known to cause distress and eating the right kinds of foods can resolve these issues. Also, getting an adequate amount of food the day and night before a morning workout will decrease your need to eat much in the hours before.
What to eat before each workout
Now you know the arguments for and against eating before a run. The next questions to consider are the intensity of the run and the timing of the run.
The body’s ability to digest a recent meal depends on the intensity of the workout. If the pace is generally easy and is something you could easily keep up for 30 or more minutes, then your body should still be able to digest a recent meal or snack and use it for fuel.
The more intense a workout is, the more blood flow will be shifted away from the stomach and to the muscles, decreasing the body’s ability to digest. Therefore, more planning needs to go into pre-workout meals as compared to meals before easier runs.
Now let’s consider the timing of workouts
As mentioned before, liver glycogen can be depleted overnight and you may wake with low blood sugar. Care should be taken in the day and night before a workout to make sure muscle glycogen stores are full. However, a small snack before a workout can help bring your blood sugar back up and maintain normal levels.
What to eat before each workout
A general rule of thumb is to eat about 0.5 grams of carbohydrate per pound of bodyweight up to one hour before a workout. For a 150 pound runner that would be 75 grams, or 300 calories worth of carbohydrate. This carbohydrate load can be achieved through a combination of solid and liquid carbohydrate, such as a bowl of cereal and 1 or 2 cups of sports drink. The sooner you eat the better so that the body has ample time to digest before an intense workout.
Afternoon or evening workouts
Afternoon and evening workouts give you more time to fuel your body with good carbohydrates and adequate amounts of fluids. It is important on these days to start off with a good breakfast and continue with a healthy lunch 3-4 hours before the workout.
Choose foods that are high in carbohydrate, moderate in protein, and low in fat. Fats and proteins delay gastric emptying. Focus on complex carbohydrates for a sustained source of energy, but avoid very high fiber foods.
Tolerances vary from person to person so you must use trial and error to find out what foods work for you and if you exercise better with having something to eat.
My recommendation would be to have something to eat before long runs and workouts so that you can get the best training effect out of your run. Easy and recovery runs do not require pre-exercise foods most of the time, just be sure to fuel your body well throughout the day for your workouts later in the week.
Final tips for eating before a run
Eat adequate, high-carbohydrate meals on a daily basis so that your body is always ready for a run or workout.
For longer runs (more than 60 minutes), choose slowly digested carbohydrates like yogurt, apples, bananas, and oatmeal. Also, consider similar foods for fueling during the long run.
Avoid sugary foods like soft drinks, candy, and sugary gels that can quickly spike the blood sugar and lead to hypoglycemia.
The more calories you eat, the more time you need to give your body to digest, especially before intense workouts.
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Here is another interesting article. Key Running Metrics . Be healthier stronger faster
Always remember that you need to do your own experiments and find what suit you best.