Cardio before breakfast

[Patronymic]

I heard that doing HIIT cardio before breakfast and having no food before is a good way to increase your metabolic rate and can enhance the loosing weight process. is this ideal? i can't really imagine people being able to push themselves to the limit compared to other times during the day.

[Scrutiny]

I heard that doing HIIT cardio before breakfast and having no food before is a good way to increase your metabolic rate and can enhance the loosing weight process. is this ideal? i can't really imagine people being able to push themselves to the limit compared to other times during the day.

Training fasted, especially high intensity forms of training can be extremely risky, with regards to losing/sacrificing muscle tissue.

Sure training fasted may have some fat-loss benefit, however the fact is that your body will be in a catabolic/breakdown/fasted state which will likely lead to excessive muscle loss.

If your goal is to lose body-fat while retaining your muscle tissue, seek to perform HIIT at a time when your body will be well nourished.
A pre HIIT meal ( much the same like an actual pre workout meal ) will provide your body with the energy and materials it needs to function optimally during the HIIT.

Not only will training fasted likely sacrifice muscle tissue, it will be a time when your body is low on energy, which will most likely lead to a poor performance in your HIIT session. HIIT sessions are the sessions where you will be wanting to dedicate ALL your energy and focus, training fasted won't be doing any favors here.

The only possible way to train without a pre HIIT/workout meal would be if you are supplementing with BCAA's pre/during the HIIT.
Even then, your energy will most likely be short and still have you in a vulnerable state.

You are correct, it is hard to imagine training with absolute maximum intensity and effort with no food/energy in your system.

One thing I will note here is that the HIIT benefits will be maximized post training, not so much during the training to the degree that what occurs with low intensity extended duration forms of cardio. After HIIT, your body's demand for oxygen will still be quite high, your metabolism will be raised and your body will be burning calories for many hours after the completion of the training.