Send us a text Rachel Tinius had the most perfect build to run a sub-3-hour marathon in Chicago. But the morning of the race, something was off. Her Garmin’s body battery read 8 percent. And the first few miles of the marathon felt like she was running 5k effort. Soon her entire body started cramping. She made it to the finish, deep in the pain cave, and really confused. She was so ready for that race. What happened? Rachel, an exercise scientist and mom of 4, reveals how her struggles were n...