We know what her strengths are, Long Slow Distance. Shelley can go forever, both physically and mentally, as she clearly demonstrated in her Spartan Death Race win. It is important to continue to train to your strengths, after all, that is what is going to continue to bring you success. Additionally, it is probably what you like to do, your strength. It is much harder to get out of bed in morning to go do the workout you are not good at.
While Shelley has good balance and above average athleticism, she could use improvement in these areas. When racing in variable conditions, it is VERY important to have sure footing. In these races, every step is expended energy. If a racer can limit the number of times they slip, loose balance, or have to slow or stop due to unsure footing, they will expend less energy and maintain a better pace.
With this in mind, we perform various foot work, agility, and balance drills such as using a agility ladder, lateral shuttle runs, karaoke, and balance drills such as this one:
Stay tuned for more on how to train for obstacle course races and improve your athleticism.