In all protocols, MD simulations were carried out with the CHARMM 36m force field or a modified version in combination with explicit water molecules described by the CHARMM version of the TIP3P water model. For locPREFMD and during the local relaxation of the averaged structure, the original version of the CHARMM 36m force field was used. For the simulations during the main sampling stage and its preceding equilibration step, a modified version of CHARMM 36m force field was applied except when running our previous CASP12 procedure for benchmark purposes. In the modified force field version, lower energy barriers for backbone dihedral angles terms between major secondary structure regions were implemented via alternative CMAP terms. This modification was meant to accelerate transitions between backbone dihedral angles but without significantly affecting protein stability since relative free energies of the conformational minima were retained. For nonbonded interactions, we used a switching function between 8 and 10 Å. Particle-mesh Ewald summation was applied to evaluate full electrostatic energy in a periodic system. Bonds involving hydrogens were kept rigid with the SHAKE algorithm. Hydrogen mass repartitioning was applied, where heavier hydrogen masses (3 a.m.u.) allowed simulations to be run with a 4-fs integration time step in combination with the SHAKE algorithm. This allowed us to sample twice as much at the same computational cost.