How they do it is warp mode in star trek?
Let aside theoretical physics and logic but if it happens, ohh…
In reality, when you achieve speeds closer to the speed of light, the mass become heavy, very heavy and one can say that tending to infinity.
Say, m0 be mass at rest
mrelative= m0/(sqrt(1-v^2/c^2)), where, c is speed of light 300000 kms/s, v is the object velocity
now plug in the data as v->c
mrelative also tends to infinity.