Answer: adrenaline

AnswerCrossword Clue
ADRENALINE

It's often in a rush

ADRENALINE

"Fight or flight" chemical

ADRENALINE

It may give you a rush

ADRENALINE
Exercise by-product
ADRENALINE
Source of some rushes
ADRENALINEWhat you feel at jam climax
ADRENALINESomething released while skydiving