Isaiah 40:31 But those who wait (to bind together by twisting– which means to be inseparably involved with one another) on the Lord. Shall renew (to change) their strength (power or might); They shall mount up with wings like eagles, they shall run and not be weary, they shall walk and not faint.
I study the original manuscripts of the Bible, and what the words mean in the language there were written.
It basically means to exchange your strength for the Lords. Where you catch the air currents like an Eagle and soar, the wind carries you. You are able to do things that are otherwise impossible with your own human strength of ability.