to ze cos jest głosniej nie znaczy ze masz dodawać do tego siły, głosnośc nie bierze sie z tego ze wyrzucisz z siebie wiecej powietrza i rykniesz, bo to nie jest specjalnie techniczne i dobre (zazwyczaj) brzuch sie nie moze zaciskać w zadnym trybie itd itd.

Support requires physical strength and body control.

Singing requires energy
It is immportant to realise that whatever the mode or style of music, it requires energy to sing in a healthy way.
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When beginners have problems reaching high notes it often because they are afraid of using physical energy or simply because they lack it. They falsely believe that singing must be a relaxed process because that is what they have been told.

The high and low parts of voice usually require more energy than the middle part and therefore are usually more difficult to sing.