Relativistic electromagnetic work-energy theorem
= Relativistic electromagnetic work-energy theorem
For $\mathcal E=\gamma mc^2$, the temporal component of the covariant Lorentz-force equation gives
$$
\frac{d\mathcal E}{dt}=q\mathbf E\cdot\mathbf v.
$$
The magnetic field does no work because $\mathbf v\cdot(\mathbf v\times\mathbf B)=0$.