Running uphill is a great workout that you can do to help build strength for your running. There are some form techniques that you should be aware of while you're doing that. When you're going uphill use your arms. I'm always telling people use your arms to get yourself uphill. Watch where you're going, keep your chin up, keep your eyes up. If you're going up, don't keep your eyes down because that makes the workout even harder to do. Look at the top of the hill, watch where you're going, pump your arms, keep your chest open. Sometimes when people get tired they tend to slouch forward and kind of bend forward, slouch your shoulders forward.
Keep your torso open, watch where you're going. Get your knees up and push off of the ball of your feet, use your legs to get us there. Go at a steady pace. You don't have to speed up. You don't have to charge up. Watch the tension in your hands. Watch the tension in your arms. Keep that pace steady, as you're cresting the hill work the pace a little bit, but follow through. Just because you get to the top of the hill it's not a reason to slow down. Keep that pace steady and work your way over the hill.