With this question firstly you can think beyond football players. Technology can be used to better understand everyone's health, including people and animals. Think about things like injuries that cant be seen, such as concussions. If a football player wanted to better understand their health they could get an MRI or use other forms of technology. Outside of injuries there is also the health aspect, you can check your cholesterol and blood rate and all that very easily now a days, making it quite easy to check if you are healthy.
Endurance
cardiorespiratory
nutrition
I'm not 100% sure but those would be my best guess
You can set up a game and have some of the kids play with her, you could ask a few kids to play with her, or the best way would be to talk to Rachel and find out why she dont want to play with the others.<span />