Creatine helps protect tiny muscle cells from shrinking when they're starved, but only when there's no sugar around — it seems to work only when energy is low.

When chicken muscle cells are starved, adding creatine seems to lower levels of two proteins that make muscles waste away — this might mean creatine helps protect muscles when there's not enough energy.

In chicken muscle cells with normal energy, adding creatine seems to boost protein building and turn on key muscle growth switches in the cells.

When chicken muscle cells are starved, adding creatine seems to boost a key protein for energy and reduce harmful molecules, which might help the cells' powerhouses work better under stress.