EE WAS HELPING OTHER TRACKMAN INSTALL ON 85# RAIL TRACK SWITCH. HE WAS BENT OVER ATTEMPTING TO LIFT THE ""FROG"" WHEN HE FELT PAIN IN HIS BACK. BODY POSITIONING WHEN LIFTING CONTRIBUTED TO THE A CCIDENT. EE WAS ATTEMPTING TO LIFT THE ""FROG"" BY HIMSELF. THERE WAS NO DAMAGE OR IMPAIRMENT TO THE MINING OPERATION OR EQUIP. THE INJURY DIDN'T INVOLVE ANY ASPECT OF COMPLIANCE, MINING EQUIP,