Breathing for singing coordinates a comfortable inhalation with controlled airflow, phonation, and the length of a phrase. No single posture cue or timed exhale proves that support is correct.
Begin with a quiet breath that does not feel full or rushed. Exhale on an unvoiced hiss, then repeat on an easy hum. Notice the difference without trying to maximize the clock.
A hand at the lower ribs can provide external feedback about movement. Keep the neck and shoulders comfortable, but do not force them to remain perfectly still; bodies and breathing strategies vary.
Next, speak the lyric and mark the natural breaths. Sing it at an easy volume and adjust the breath location before adding intensity. Phrase planning is often more useful than simply taking more air.
Over-breathing can feel rigid, while under-preparing can shorten the phrase. Explore a comfortable middle rather than targeting one percentage of lung capacity.
Duration is one observation, not a direct measure of lung capacity, vocal-fold closure, or technique, and it is not a diagnosis. Compare the same task under similar conditions and stop before light-headedness or strain.
Pain, recurring hoarseness, or unusual breathlessness is not a training score. Stop and ask an appropriate health-care provider about persistent concerns.