What problems do you think athletes/people can run into when they are tracking their HR from a fitness standpoint?

Which type of nerve creates a 'mental map" of the relative positioning of the body at any given point in time?

Ineed i have a headace and ive had 3 bottles of water as well as milk and i cant take any pain meds cause they will interfere with my current what else can i do?

For a break to relieve stress, it needs to be at least half an hour. true or false