When practicing IF as a lifestyle it is important to understand when and how to train optimally. Training done in the fed state will have a different impact on your body than training during the fasting state. There are a lot of myths and confusions regarding training during the fasting state and whether or not we should do it.
Let’s discuss the different impacts of training (depending on when you do it) so we can clear up these confusions.
Training during the Fasting State
(anytime during your fasting hours – preferably after six hours of fasting)
Training whilst fasting can increase glucose tolerance, reduce insulin sensitivity, increase abdominal fat burning blood flow as well as increase muscle building with strength exercises. During training the body relies on stored glucose (glycogen) and fats to power itself. As the digestive system is in stand-by and there is no food from which to draw energy, the efficiency of training during fasting is improved.
“Exercise in the fasted state facilitates fibre type-specific intramyocellular lipid breakdown and stimulates glycogen resynthesis in humans.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1464435/
Note: You are only allowed zero calorie drinks before training. ANY calories consumed (like on The 5:2 Diet) will put you in a Fed State for your training. Even a handful of nuts or an apple will put you into a Fed Training State. In other words, no matter what type of IF you practice, pay close attention to your calorie intake prior to any training as the restrictions for Fasting Training may be stricter than your chosen IF fasting guidelines.
Training during the Fed State
(anytime after you have broken your fast)
No matter if you eat 30 minutes or three hours after breaking your fast, you are in the fed state. Training during the fed state means that there is food still digesting in your body hence your Parasympathetic Nervous System is activated, promoting a state of rest and digestion. If you must train during the fed state, a gap of 2.5 to 3 hours between your meal and your training is ideal. Of course, this timing depends on what your meal consisted of as well as how large it was – it could take up to 6 hours (or more!) to completely absorb your food and for your insulin levels to return to baseline.
If you train prior to your insulin levels returning to baseline, the insulin still present in your body will inhibit the breakdown of fat both during and after your training session. Your body, while burning some fat, will not be functioning optimally as your body can more easily access the digesting food for energy rather than your stored energy (glycogen).
“After a meal, insulin suppresses lipolysis through the activation of its downstream kinase, Akt, resulting in the inhibition of protein kinase A (PKA), the main positive effector of lipolysis.” https://www.ncbi.nlm.nih.gov/pubmed/20733001
What happens after training when we eat?
Well, this also depends on whether you trained during the fasting or fed state. There is a concept known as ‘calorie partitioning’ which simply defines what percentage of calories consumed at any given meal will go towards muscle building and what percentage will go towards fat storage. Food consumed after a Fasted Training Session will use the majority of the calories consumed to restore glycogen stores and towards the building of lean muscle. Food consumed after a Fed Training Session will use the majority of the calories consumed to restore fat reserves. This is because we have not depleted our glycogen stores (carbs stored in the liver and muscles) and so the body does not need to replenish them, leaving the calories floating about looking for a ‘forever home’ and the body’s fat cells are a welcoming place indeed.
As with all decisions regarding your health and wellness level, choose wisely when and how to train. Awareness of your bodies limitations and abilities during fasting is your best guide to optimal training.
Always remember ...
A key component to successful IF is your nutrition during your feeding window. Be sure to focus on nutrient dense foods to ensure your body receives the vitamins and minerals it needs to perform optimally.
Remember – IF is a lifestyle choice, one that can be practiced each and every day of your life. Explore the IF options and find the one that fits best into your schedule and preferences.
Keep at it … it has taken some time for your body to learn its current feeding schedule, allow it time to adjust to a new schedule now so that you can fully reap the health benefits of IF.
IF is a way of eating that employs a fasting window of 24 hours or less. IF has been used to facilitate weight loss, build lean muscle mass, improve digestion, decrease inflammation throughout the body as well as to increase energy levels.
IF is a way of life, not a diet. Our bodies are designed to fast and feed in regular cycles – our first meal of the day is after all called BreakFast!
We are all very good at the feeding part but we miss the opportunity to take full advantage of the fasting part. During fasting hours, our bodies continue working and when not overwhelmed with the work of digesting food, our bodies can focus on repairing cells, healing illness as well as detoxifying our blood.
Employing IF as a lifestyle choice facilitates our physiological organism to function at a more optimal frequency, thereby impacting our health and well-being in a plethora of ways – from digestive health to emotional balance, it all begins (and ends!) in the gastrointestinal track.