Have you heard of fasted workouts? It’s okay if you haven’t, but it’s becoming a more well-known practice and is definitely a not-so-hidden secret for fitness trainers. So, here’s the scoop on doing a fasted workout.
What exactly is a fasted workout?
As with any conversation in the fitness industry, there is mixed information out there for you on what a fasted workout actually is. You’ll read a lot of articles that suggest at least 3 hours after any type of meal before you workout, but a true fasted workout would be a workout done after at least 6 hours without any food ingested.
Some suggest as much as 18 hours of fasting, but if you’re just starting, let’s start slowly, shall we?!
Personally, my fasted workouts range from 10-12 hours after my last meal. I don’t eat after 8pm (unless there’s’ wine, then all bets are off) typically and I workout around 7am every morning.
What are the benefits of fasted workouts?
Fat burning. A lot of people have heard to do fasted workouts because of its magical power of fat burning. And, they’re not wrong. Starting your workouts in a fasted state allows your body to start burning fat faster for energy. This is a trained result, so don’t expect immediate results (as with all things fitness).
A quick lesson on how your body gets energy: Your body breaks down sugar for energy. Insulin is released to drag sugar into the cells to be converted to energy (sugar can’t go directly into the cell, it neeeeeeds insulin). After about 6 hours of fasting, your body enters a fasting state and quickly burns off stored sugar and moves on to breaking down fat, converting it into ketone bodies to be used for fuel.
During a fasted workout, if done correctly, you start your workout already getting some of your energy from fat. You’re already in a fat-burning “zone” and can increase your fat burning with a workout in this fasted state.
Insulin levels decrease. Excess insulin in your body is not good for you, in fact, it results in fat gain and can lead to Type 2 Diabetes. How can you decrease your insulin levels? Fasting works. So does exercise. Pair them together and BOOM…you’re an insulin decreasing ninja!
Exercise performance. We walk around carrying a huge energy supply in the form of fat. However, our bodies first burn sugar for energy and once that sugar is depleted, it’ll move into burning fat for energy. By doing fasted workouts, you train your body to tap into fat burning faster. You’re really just training your body to tap a different energy supply sooner. So, you train your pathways to train your body. Fun!
I like to call this metabolic flexibility. When your body can bend and twist and find different ways to get energy faster, you’re metabolically flexible and you get to burn a lot more fat during your workouts.
Muscle and brain fountain of youth? Okay, I could start spouting off about a bunch of different hormones, brain-derived neurotropic factor and muscle regulatory factors but I think I may lose you. So, let’s just say by exercising while fasted you may lay down some new neurons and new muscle cells. Basically by doing this type of workout you’re keeping your brain, neuro-motors and muscle fibers young.
Do’s & Don’t of Fasting Workouts
If you’ve never fasted before, please try fasting before you combine fasting with a workout! You need to train your body to tap into your fat stores and that takes time. So, allow your body time to train and figure out how to tap that fat quickly!
Start slowly. Try doing a walk or hike or an easy workout while fasted before you try any type of interval workout. You need to see how you feel and again, you need to train your body and get used to working out in a fasted state.
Do not do a long duration fasted workout. If you’re planning on a long run or anything over 40 minutes, you’re going to want to fuel properly before your workout/event/race. Your body does need fuel for those longer duration workouts, so a fasted long run is a terrible idea.
Eat after your workout. This is particularly true if you’re doing a weight session. Your body needs protein to help build and repair the muscles you destroy and tear to shreds (you beast!) when you strength train, so you need to refuel with a healthy meal after your workout. So eat all the good stuff.
Listen to your body. This is probably my best piece of advice. If you feel faint or nauseous while doing a fasted workout…STOP! Today is not your day. You can try again another day, but go eat an apple, drink your water and let your body catch up.