Do you prefer to have a snack first or workout on an empty stomach?
As with most exercise and nutrition related advice, the answer to this question depends on many factors. This can come down to a personal preference and what works for you. What works with some may not work for others. It can also come down to the time of day and your schedule.
I must have something in my stomach before I can work out, otherwise I have no energy and feel like I’m going to throw up. For some people, eating before exercising can make them feel unwell and then other people may not eat before exercising and feel unwell. But how do you know what you should do?
We will go through the pros and cons to help you to decide if you wanted to try fasted exercise for yourself.
What does fasted cardio mean?
Fasted cardio is the exercise you do when your body has entered a ‘fasted state’ which happens when your body is no longer processing food which, on average, is around 3-6 hours after eating.
Fasted cardio is commonly done first thing in the morning before having breakfast, but this doesn’t mean that is when you have to. It can be done at any time of the day when your body is in a fasted state.
Once you are in a fasted state your insulin levels are at a low or baseline level. When insulin levels are low, there isn’t readily available energy in the form of glucose so your body must rely on stored energy such as glycogen and fat to fuel muscle movement instead.
Fasted cardio is sometimes recommended as it might help you burn more fat throughout the day. The idea is that when you work out when you haven't eaten recently, you are burning fat (stored energy) versus the energy from the food that you just consumed.
If your blood glucose and glycogen are completely depleted this can sometimes result in muscle tissue being used for energy (usually if you were at this stage, you wouldn’t be feeling great either). This is a extreme situation as most of us would have a meal before going to sleep and the likelihood of completely depleting your blood glucose and glycogen stores while sleeping is pretty slim.
You may feel too depleted and sluggish so working out while fasted might not be the best idea.
What type of exercise should I be doing on an empty stomach?
Low – moderate intensity aerobic exercise is best on an empty stomach.
As long as fasted cardio isn’t taken to the extreme it is safe. You need to remember your body needs fuel to function, so an intense 2-hour cardio session or a heavy weight session may lead to a safety risk. You might also be more likely to get dehydrated during fasted training so keep drinking plenty of water.
So when should you eat before a workout?
If you are doing a high intensity workout you should have a light snack first. Something that is easy to digest, and have a larger meal after your workout. If you do have a larger meal before exercise I recommend leaving at least an hour between eating and starting a workout, just to give your food time to digest. Having a snack before you exercise can also mean you will be less likely to overeat after your workout.
If you are someone who prefers to train after dinner, allow a couple of hours for digestion or split your meal into two smaller meals to have one before and one after your workout.
Another time you should eat before training is if you are someone who feels nauseous during your training sessions even though you haven’t eaten anything for a few hours. This is a sign that you should have a light snack before you exercise, even if i is just a banana. That way you have something in your stomach but not so much that it will make you feel sick. This is a good thing to do if you are training before you next main meal, whether it is first thing in the morning or late afternoon. Some people just do not suit fasted cardio and that is okay.
Should you try fasted cardio?
It is completely up to you. If you are someone who feels drained or gets nauseous training on an empty stomach, I wouldn’t recommend it. If not, then you can always give it a go and see if it is for you.
If you do decide to try, start off small, try eating something light like a banana or piece of toast before the workout and see how you feel. If you feel good, next time try without food, but still make sure you consume enough water.
To get the most out of your workouts, you should do what works best for you. This could be eating a pre-workout snack to give you the energy for exercise, or exercise on an empty stomach. Do what makes you feel the best, when you feel good you will be more likely to train consistently.
Training consistently is going to give you better results than whether you eat before a workout or not. At the end of the day, no amount of ‘fitness hacks’ can get you the results that you will get if you simply train consistently, over time and follow a healthy lifestyle. Lasting results need to be sustainable over time and form a natural part of your life.
Let me know in the comments, what works best for you? (I’m a pre-workout snacker)