Ive deal with and use photoshop daily.. upon reviewing images, I see no reason to conclude it was definitively used. Pixelations such as the one near his left bicep can happen when the jpeg algorithm encounters sharp gradations of contrast, such as the shadow falling on his chest from the bicep itself. Also, following his singlet from the shoulder down, seems it would be covered completely by the dumbell as shown. Even if it should be partly visible, this is still not conclusive evidence because the strap could be shifted on his body.