If you ever had a running-related injury you know the importance of strength training. The main reason why it is recommended to increase your weekly mileage by no more than about 10 percent is to allow for physical adaptation of your muscles to the stress of exercise. So to me, a seasoned runner with prior running-related injuries, this means: go to the gym and meet up (finally!!) with my favorite personal trainer Joe for a circuit training! My body will thank me on half-marathon day. In this video Joe demonstrates an easy to follow but very effective routine.