Exercise while Fasting - How to time your workouts with fasting | Jason Fung

can you exercise while fasting i'm going to cover that coming right up and stick around to the end when i'm going to go over james's story who was able to lose almost 50 pounds and what regimen he was following so stay tuned [Music] a lot of people think that they can't do anything while they're fasting i hear this a lot i have work to do i am i have a very physically active job so i need to eat for energy so a lot of people feel that if they are not eating that is fasting they really should be trying to limit their exercise limit their activities remember that your body has the ability to store calories which is just food energy so when you store it you also have the ability to take it back out of storage and that's what happens when you're fasting your body is essentially like a hybrid car which sometimes can use gas and sometimes can use electricity and it can switch between the two well it's really the same thing with our body our body has the ability to use energy that's coming in like the glucose from your food but it can store some of that away so that you have energy when you're not eating and you can either use the food which is calories or you can use the calories that are stored away which is body fat that's really all body fat is so if you are carrying body fat you could have 100 000 200 000 calories worth of energy just sitting in those stores so you can use them that's really why you have them so the answer to the question can you exercise during fasting is yes your body is going to be able to find energy whether you're eating and it's going to take the energy from your food or whether you're fasting in which case it's going to take the energy from your body fat and also from your blood glucose because it needs that source of energy the simple thing to think about when you're fasting is really that you should be doing everything that you normally do when you're not fasting the only difference is that you're allowing your body to use the energy that's been stored away so if you're normally going to go for a run even if you're fasting you should go for a run if you normally are doing a full-time job then you do exactly the same thing but you don't eat and that's the only difference there are some nuances in terms of high intensity workouts but for most people exercise while fasting is totally acceptable and you shouldn't think twice about it the second question i often get is what's the best time to train and the answer to that really is whenever you have time however the best thing is really to do it towards the end of your fast and this is something called training in the fasted state so if you're doing a 16 hour fast for example or a 24 hour fast you might eat breakfast and then you're not going to eat again until the next day's breakfast so what you would do is go all the way through and then just before your meal that's when you would put in your training or your exercise so you're going to get your body in the state where it's around 16 24 hours fasted and then you exercise and then you eat that's when you break your fast there's a couple of good reasons why training in the fasted state makes a lot of sense remember that when you're not eating certain hormones are going to go down and certain hormones are going to go up insulin is going to go down and that's going to tell your body hey there's no food coming in there's no calories that are coming from food we need to look for our sources of stored energy which is the glucose in the blood and also the body fat so it's going to switch over the the energy for to that source and then the second thing is that certain hormones are going to go up and these are called the counter regulatory hormones and one of the most important counter regulatory hormone is part of the sympathetic nervous system and this is the so-called fight-or-flight response and the hormone often associated with that is norepinephrine and the effect of this norepinephrine an increase in sympathetic tone which is often mediated by the vagus nerve is that it's going to activate the body so when you're fasting you're not actually shutting down your body you're activating the body into this fight or flight response so the reason it does that is that it wants to take the energy that's stored away and push it out into the blood so you have ready access to energy in case you need to fight or you need to run away very very fast so when you have the increased sympathetic nervous system the increased noradrenaline well the training is going to be a little bit easier because you've already started to activate the body and therefore the training is going to be easier the second thing is that growth hormone is another one of these counter regulatory hormones and when you don't eat insulin falls growth hormone goes up so that might seem very strange why is your body activating growth at a time that there's no nutrients and it's because it's a balance it actually doesn't want to grow because it's shutting down its nutrient sensors at the same time it's increasing the growth so overall the net effect is zero however when your body starts to eat and it has all this growth hormone it's going to start to repair all of the things that are needing to be fixed so when you do exercise remember you're doing a little bit of damage to the body when you lift a heavy weight you're actually causing little microscopic tears in the muscle which sounds really really bad but in fact that's how you get stronger it's in the process of repairing those little microscopic tears that the body has to make it stronger in order to withstand the stress so you have to put the stress on the body and then repair it in order to get stronger you don't just get stronger by itself and so having this uh training in the fasted state is beneficial from two hormonal standpoints one is that you're activating the system so you're going to be able to train harder and second is that your growth hormone is going to go up so that you're going to recover faster so that's a huge advantage to training in the fasted state so once again that is doing your fast doing your exercise and then eating and hopefully you eat plenty of protein and all the good nutrients that you need in order to build the muscle because there's a period of time just after the exercise where your body is primed to build muscle and that's when eating more protein and so on can be very advantageous let's get back to james's story james had always been on and off dieting he had tried lots of different diets he had lost weight but he was never able to keep it off in fact he had even tried ketogenic diets and intermittent fasting and he sort of lost faith in it because he was never able to maintain his weight however there was a difference this time in that he decided to book a coach with the fastingmethod.com and this is somebody that's going to be able to give advice but more importantly keep people accountable and this is the exact reason why people in athletics always use coaches michael jordan might have been the greatest basketball player ever but he always had a coach why because you don't want to let your coach down it's somebody who's going to say hey come out to the gym make sure you work hard and that's what a weight loss coach can do as well and luckily james was able to find one with john and he was able to lose almost 50 pounds his regimen was starting with a 22-hour fast sort of a one meal a day monday wednesday friday and then as he began began to get used to it to go to a 40-hour fast and then doing that in order to get some of the weight down and when he did that he started feeling better he lost the weight he stopped snoring and that's great news he continues to work with the coach so that he can maintain it off which really is much harder than losing weight in the first place that's great work you did there jane hopefully you learned something this week if you did please share it maybe you can help somebody else as well and i'll see you next week

Channel: Jason Fung

Views: 570,866

Keywords: exercise while fasting, working out while fasting, intermittent fasting and working out, intermittent fasting and exercise, intermittent fasting workout, fasted training, exercise while fasting - how to time your workouts with fasting, how to time your workouts with fasting, time your workouts with fasting, workout while fasting, fasting workout, fasting workout benefits, can you exercise while fasting?, physiology of fasting and exercise, training in the fasted state

Id: Hun9pmORChw

Length: 9min 23sec (563 seconds)

Published: Sun Apr 10 2022