Early morning workout and weight loss.

To reduce weight, early morning exercise is recommended but question is why?
Let's get back to basics before answering this question.

Body has three sources of blood glucose to maintain level uniformly.
1) Food.
2) Liver Glycogen.
3) ‎Gluconeogenesis.

Now, Liver Glycogen can provide energy for around 12-18 hours. Gluconeogenesis uses lots of energy to maintain blood glucose level. Between dinner and breakfast we have gap of around 12 hours. This mean before taking breakfast  liver glycogen stock is null! And body is using now gluconeogenesis to maintain blood glucose level and as you know it's going to take hell lots of ATPs to maintain it. Also, exercise uses lots of energy. Hence both in turn helps in reducing body weight.

What is wrong with evening workout?

Suppose a person has taken lunch around 2 pm and he's working out around 5-6 pm. Which stores will be used by body to maintain glucose level - food obviously! Hardly any Liver glycogen is used up. Also extra food will be stored.

That's all!

-Demotional bloke