Although I knew I was going to run the SJT 50K this year, it was hard to feel very confident about it. I had to miss some runs due to recurring issues with my shin splints and tendonitis. To make up for those lost runs I put in double time at the gym, taking spinning classes immediately followed by an hour of laps at the pool. I sometimes threw in some weight and core work into the mix. On days when I've felt especially motivated I've spent up to three hours at the gym usually early in the morning before I start work.
As a result I feel that my conditioning has improved even when I had to stay off my feet to help my body recover from whatever may be ailing it.
Running is still my favorite workout, though it is nice to know that when I have to take a break from it, there are other forms of training I can use so that I'm able to maintain my fitness level.