Going to the gym really early

do what works for you. you don't necessarily have to eat breakfast, and this is coming from a person who never ever sets foot out the house without eating breakfast, except very rarely.

but at 5 in the morning, you can skip on breakfast if you like

i usually eat banana/cereal/milk/tea/(and take my fish oil) or waffle/eggs/banana or oatmeal/banana

but fasted cardio is good if it doesn't make you feel sick/weak.

I often work out without eating first.

I do cardio at 6am. I usually eat a very light snack before. Its usually a mix of both carbs and protein. I have noticed that it always makes me feel better through my workouts. After, I eat another light snack that is mostly protein. Later on I will eat breakfast. It works for me.

I'm starting at a new school at the end of the month for my teaching placement and I KNOW that if I leave it until the end of the day to workout, I'll be too tired and have too much to do. My gym is just a few minutes from the school, I chose it for that very reason, so I plan to get there 3 times a week for when it opens at 7am, workout for 45 minutes, quick shower and be at school for as soon after 8 as possible. Like you I've had to try and think about food and how to do it so I've had some earlyish sessions this morning to test it out.

Like others have said, you really do need to eat before the gym. Not eating for 24 hours isn't healthy anyway but then going to the gym at the end of that is even worse, so ignore that advice!

Here's what I've found works personally. Wake up, have a glass of water (stops my post gym headache) and grab a banana and then get ready. That gives my body at least 40 minutes to deal with the banana before I get to the gym and then I'll do my workout, drink plenty of water and eat breakfast after. The breakfast bit I'm still working on as I'll be at the school so can't have just anything. People have suggested things like egg sandwich, protein shakes, muffin in a cup type things if you have to eat after whilst on the move. I usually do carbs before to fuel the workout and then high protein after to refuel my muscles and help them recover, works well for me.

Regardless of what time I go to the gym, if I don't eat something, even if it's one piece of toast, I get really dizzy.

Like others have said, you really do need to eat before the gym. Not eating for 24 hours isn't healthy anyway but then going to the gym at the end of that is even worse, so ignore that advice!

Evidence that not eating for 24 hours isn't healthy, please?

It's called common sense. Your body needs fuel to run. Food is fuel. Food gives us energy. It's like driving a car with no gas and wondering why it won't go.

Here, read this. http://www.livestrong.com/article/134155-what-are-side-effects-not-eating/

Like others have said, you really do need to eat before the gym. Not eating for 24 hours isn't healthy anyway but then going to the gym at the end of that is even worse, so ignore that advice!

Evidence that not eating for 24 hours isn't healthy, please?

It's called common sense. Your body needs fuel to run. Food is fuel. Food gives us energy. It's like driving a car with no gas and wondering why it won't go.

Here, read this. http://www.livestrong.com/article/134155-what-are-side-effects-not-eating/

Your fat stores are used for fuel as well as food. That's what your body uses once it stops using food for fuel and that's how you lose weight. Not eating for 24 hours will not make you starve, your body still uses food that it ate the day before for fuel. Then it starts using fat stores for energy. That's the brilliant thing about the body, it was DESIGNED to last without food.

Here, read this:
http://www.marksdailyapple.com/fasting/#axzz1s6cQdupu
http://www.leangains.com/2010/10/top-ten-fasting-myths-debunked.html

The link you sent me describes what would happen if you stopped eating for a long period of time - eg. LONGER than 24 hours. You will not start starving after 24 hours.

And just because something is believed and accepted by the general populace doesn't make it true.

Like others have said, you really do need to eat before the gym. Not eating for 24 hours isn't healthy anyway but then going to the gym at the end of that is even worse, so ignore that advice!

Evidence that not eating for 24 hours isn't healthy, please?

It's called common sense. Your body needs fuel to run. Food is fuel. Food gives us energy. It's like driving a car with no gas and wondering why it won't go.

Here, read this. http://www.livestrong.com/article/134155-what-are-side-effects-not-eating/

Your fat stores are used for fuel as well as food. That's what your body uses once it stops using food for fuel and that's how you lose weight. Not eating for 24 hours will not make you starve, your body still uses food that it ate the day before for fuel. Then it starts using fat stores for energy. That's the brilliant thing about the body, it was DESIGNED to last without food.

Here, read this:
http://www.marksdailyapple.com/fasting/#axzz1s6cQdupu
http://www.leangains.com/2010/10/top-ten-fasting-myths-debunked.h

The link you sent me describes what would happen if you stopped eating for a long period of time - eg. LONGER than 24 hours. You will not start starving after 24 hours.

And just because something is believed and accepted by the general populace doesn't make it true.

The problem with your logic is that when your body doesn't have the proper food stores to use as energy to fuel your workouts, it will use muscle FIRST for energy. Only AFTER a large portion of your muscle is depleted will it attack fat storage. When trying to lose weight muscle is your friend....the more muscle you have the more calories you will burn, even in a rested state.

I usually just take a coffee with protein with me to the gym and drink that while I'm working out. If I eat anything before makes me feel pukey.

Like others have said, you really do need to eat before the gym. Not eating for 24 hours isn't healthy anyway but then going to the gym at the end of that is even worse, so ignore that advice!

Evidence that not eating for 24 hours isn't healthy, please?

It's called common sense. Your body needs fuel to run. Food is fuel. Food gives us energy. It's like driving a car with no gas and wondering why it won't go.

Here, read this. http://www.livestrong.com/article/134155-what-are-side-effects-not-eating/

Your fat stores are used for fuel as well as food. That's what your body uses once it stops using food for fuel and that's how you lose weight. Not eating for 24 hours will not make you starve, your body still uses food that it ate the day before for fuel. Then it starts using fat stores for energy. That's the brilliant thing about the body, it was DESIGNED to last without food.

Here, read this:
http://www.marksdailyapple.com/fasting/#axzz1s6cQdupu
http://www.leangains.com/2010/10/top-ten-fasting-myths-debunked.h

The link you sent me describes what would happen if you stopped eating for a long period of time - eg. LONGER than 24 hours. You will not start starving after 24 hours.

And just because something is believed and accepted by the general populace doesn't make it true.

The problem with your logic is that when your body doesn't have the proper food stores to use as energy to fuel your workouts, it will use muscle FIRST for energy. Only AFTER a large portion of your muscle is depleted will it attack fat storage. When trying to lose weight muscle is your friend....the more muscle you have the more calories you will burn, even in a rested state.

Only in prolonged fasting does protein catabolism become an issue. This happens when stored liver glycogen becomes depleted. In order to maintain blood glucose, conversion of amino acids into glucose must occur (DNG: de novo glucogenesis). This happens gradually and if amino acids are not available from food, protein must be taken from bodily stores such as muscle. Cahill looked at the contribution of amino acids to DNG after a 100 gram glucose load. He found that amino acids from muscle contributed 50% to glucose maintenance after 16 hours and almost 100% after 28 hours (when stored liver glycogen was fully depleted). Obviously, for someone who eats a high protein meal before fasting, this is a moot point as you will have plenty of aminos available from food during the fast.

source - leangains.com