Many people work on “physical fitness”. In that world, feeling the pain isn’t uncommon. Pushing the body to go past its natural limits comes with the territory. If you do that enough, you deaden yourself to pain and learn to ignore your body’s natural wisdom, and then you run a greater risk of becoming seriously injured.
Cultivating awareness of the body is exactly the opposite of “getting ripped”. It has to do with drawing your attention into your body and noticing what, how and where it feels something. If you ask it to do something it typically doesn’t do, you might not get much of a response or have much control. If you are not deeply in touch with your body, you may not only lack strength and coordination but also may not be able to direct specific movements even if you understand exactly what you want to move.
Even dancers and athletes can be out of touch with their bodies when they enter into activities that require a different kind of movement than that which they typically use. All dancers know that they have to adapt to each new choreographer and depending, that can be easy or take a bit of time. Being a great tennis player doesn’t automatically make you good at baseball, even though both require great hand/eye coordination.
Physical awareness happens best in a body that is in good health and decent shape but it is not limited to that condition. People who are ill can have great physical awareness and people who are really strong and powerful can have very poor physical awareness. Also, noticing subtle changes in the body takes some degree of sophistication in awareness, as the smaller the change or reaction, the greater the level of conscious attention (awareness) has to be.
Generally, unless you are familiar with “mindfulness” techniques that are directed specifically towards the body, you may not even know if you are physically aware or not or if the awareness you think you have is all there is. You can only become more knowing by experience and the experience has to be anchored to intention. Anything else is not helpful. Only physical awareness is physical awareness. If you sing and you have not done something to increase your conscious awareness of every part of your body and what it is capable of, you don’t know it well enough to do yourself much good. How would you know that? You wouldn’t until and unless you participated in some kind of bodywork.
If you have the opportunity to work with anyone anywhere who will help you gain a very personal, and perhaps unusual, perspective on what it is to live in, experience through and have a body, take it. This can only benefit you in every aspect of your life but most particularly in your singing.