It is a very good prompt because the modulation in the vocal chords are impacted to a great extent by the way one regulates breathing.
There must be fundamentally a natural synergy or one nurtured through intelligent and rigorous practice.
When we listen to some singers and some compositions we can notice this and appreciate.
That's why classical music vibrates with subtle frequencies of our biological cells, though we may not be analysing it in labs but relishing it, more powerfully, if we are also fortunate enough to nourish some additional ingredient called aesthetic sensitivity as a part of culture or tradition.
Actually most of the compositions of Saint Tyagaraja and Saint Sadasiva Brahhendra are actually carved for easy and enjoyable rendering soothing to the brain, nerves and breathing system as a whole.
If learners, practitioners and performing artists observe closely and grab that then they would be naturally able to develop these skills.
Old films in most Indian and Italian had compositions in such a way that the emphasis was on sound structures based on simple harmonic motions or lilting notes which synchronized with body pulses.
Listen to Mukesh or Hemanth Kumar or MKT one can notice this.
Like the sonnets in literary poems the songs of classical music and tunes have a nice structure of what we call in classical carnatic music Pallavi, Anu pallavi, Sharanam, Chittaswarams etc.
The multiple sangadhis ( refrains or repetions) are gradually and incrementally improvised to ensure the voice and breathing do a synthetic display like synchronized swimming.
Now to a few nicely nurtured ones:-
In the following listen to Brochevarevare ninnu vina in 1972 krishna gana sabha concert with Lalgudi Jayaraman and Trichy Sankaran
Now coming to Naturally gifted ones:-
GNB's Radhasamedha listen to when he sings ' krishna'
All time favourite of grand rendering and great gimmicks
Some compositions of Saint Tyagaraja are the most nutritious, elaborate and tasty Thali( full meal) one can ever taste.