I'll add a little to what Pete said.
1) There's a part of you that may know certain excercises will be more beneficial to you, so by all means, do what you gotta do.
2)In front of a mirror can also help in visualizing which directs the energy better(yi guides the chi).
3)The ideas presented in Qigong can be used while performing any activity to make them/you more efficient/healthy.
4)Try eating after excercising. If you shower after excercising and your body temperature is up, don't take a cold shower, the drastic change in body temperature could cause you to faint.
Stay curious.
