So you have 2 things here, both very important. On the one hand you have this "born again" thing. On the other hand you have this issue of there being "no life in you". Clearly Jesus was talking to living people when he said this so the "life" he was referring to was something more than just existing, being. What do you think that was?
I know this wasn't asked of me, but I would enjoy giving my answer to your question.
The additional life which is mentioned is what comes along with the Holy Spirit within followers. It is the LIFE Jesus was talking about when he spoke to the woman at the well. It is an additional measure of life given as a gift from God unto people already living. I suggest humanity was given
two measures of life in the very beginning. We were
first a living spiritual entity existing within God. Then
we were imparted into a living physical body.
The measure of life granted unto our flesh came by the addition of a mist of water upon the ground just before God formed the body for Adam. Genesis 2. An example of such a miracle of creations was recorded in the NT. Jesus took the ground and added a measure of divine/water/spittle from his mouth to form living functioning eye balls for a man who had had none since birth ... Well, so did the Lord God take the ground and added a mist coming straight from Him as God to form eyeballs for mankind in the beginning. Plus these elements called ground having life in it was used to form the rest of Adam's body. Therefore, if we have the Holy Spirit of life in us, we have the additional measure of life eternal promised to follows of the Messiah.
Secondly, The Holy Spirit is also a personage/individual of the God Head. As God in us he has an additional work to perform toward our salvation. He is the power which holds us until we appear in the Kingdom of our Lord. He is our comforter, our teacher, our strength in times of trouble...
A long time ago after seeing people pass out under the power of the Holy Spirit on TV ministries, I asked God why didn't I as a Christian feel the power of the Holy Spirit?
God answered this way, "Do you feel your liver?" I said, "No." He said, "Why not?" I said, "Because it is created to be a part of me. I wouldn't notice it unless something went wrong." He said, "So?" Then I understood: The Holy Spirit was designed to become a natural part of me; so, it is like the wind which is invisible and I cannot discern from where it comes or goes.
Yet, I know it is there for sometimes God the Spirit has chosen to speak to me as he had answered my questions just above.
In times of trouble and sometimes with little things, he has let me know he is there. Those times have really strengthen my faith that God is real, alive, knows what is going on in my life and cares and keeps his promises. Learning to listen for his voice is a challenge and I hope he is not speaking all the time and I'm just not listening... and missing the great things he may want to say. ???