Breakfast before or after running?

I've always heard if you're doing a light workout it's okay to eat after but if you're like marathon training//an hour+ workout first thing try to get at least something small to fuel it.. Honestly tho it's prob personal preference tho I imagine if you are doing an intense workout after not eating for 5+ hours you could get fatigued more than you might if you have a pre-workout snack.

If you want to switch from burning glycogen to burning fat, fast then exercise.

There's no set rule. If you eat immediately before you exercise, you aren't really fueling the body for that workout... you're just inputting sugar to spike your blood sugar for a while, which will give you quick energy, and telling your body to start metabolizing faster again after its fast. It is a matter of preference. Some people with very fast metabolisms will get up an hour or so before their workout to eat something that they can use as fuel during. Others will rather use the energy they've stored overnight before inputting newer, not as clean energy, so they will exercise on an empty stomach.
That being said: Running, it does not matter. Heavier workouts which include strength training will probably have better benefits with quick fuel to contract/detract those muscles. Unless you're at a consistent deficit in your eating, with little body-fat, your body will always have enough fuel to get through a 3 miles run or less. The quality of that workout is another matter.

By the way, this is all mostly personal opinion backed by experience and some research. If you want professional/medically informed information, maybe try some of the articles from Runner's World.com?

edited to add that I almost always do my morning run, sometimes up to 15 miles, on an empty stomach. 13+ milers, I'll maybe bring a Gu or sommat, and my run usually consists of 6-8 miles and I can run them sub-9 minute no problem even on an extra stomach. I've trained my body to be that way though. At the beginning of the running regimen, it may be a bit difficult. And it is VERY important after a morning run on an empty stomach to refuel properly afterward, otherwise you will most definitely crash.

I can't workout after meal. so I always go fasted
Try both and see what suits you best...

There isn't a right way or a wrong way. C25k isn't THAT intense, so you could try doing it fasted if that suits you. But if you find you run out of energy, then you should try fuelling beforehand with something light like a banana or a piece of toast with peanut butter.

Most research points to evidence that cardio first thing in the morning before eating will burn more calories from fat than exercising later on in the day after eating. Mike Matthews explains this quite well and cites the relevant research.

If you do train early on an empty stomach, make sure you hydrate really well beforehand. Get some serios water down first!

Interestingly, there is also strong reserach to show that weight training and cardio should not be done back-to-back. Again, the reasoning is quite complicated, but in a nutshell - cardio prevents / reduces production of growth chemicals, so the cardio is likely to reduce the usefulness of the weights. The suggestion is that if you must do both types of training in the day, do cardio before breakfast, and weights late afternoon.

I can't workout after meal. so I always go fasted
Try both and see what suits you best...

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I can't workout after meal. so I always go fasted
Try both and see what suits you best...

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^Another for this. Do what works for you.

I'm looking to start my C25K soon and I just had to know what way worked better.
I used to do competitive sports before and for my personal training, I always ran a few minutes before eating breakfast.

So, what would be better?
I'm looking to tone my body up as a lose the last 20lbs. I just dieted my way through those 15lbs and I'm going to start running again not only to maybe fast track my weight loss but also to tone myself up.

(FYI, I'm also going to start bringing back some light weight training with this.)

For body composition purposes, it doesn't matter. The question is how your body responds. Do you feel sick if you eat first? Do you feel sick if you don't?

I've done it both ways and either works for me, personally.

I wish my body were consistent enough for me to have advice to give, but figured I'd mention it because nobody else had - what works best for a given person can also vary. Some days I'm a champ running 8 miles on empty. Other days I drag 3 miles and wonder why on earth I didn't swig some OJ first. I normally try to eat, but often forget (AM isn't terribly lucid for me). Before a race, I can usually get down some yogurt and a tiny bit of oatmeal, the jitters keep me from wanting more. But I've also had amazing long runs on evenings only an hour after a decent sized dinner.

So not only try it and see what works for you, but understand that even that may vary wildly from day to day. In the C25K, the MOST important thing to do is to put your shoes on and get the run done. Let it be ugly, slow, annoying, but get the miles under your shoes. Once (if ever) you start working on performance (distance or speed or both), it will start to matter how/when you eat much more.