During her warm up diane moves her arms side to side for 12 repetitions using gradual in control movement this type of stretching is called

The answer to this is true

Because without physical activity, the body has extra "energy" if you will, and so when it is time for bed you are not tired, so you end up staying up all night. also there is probably an effect on your internal clock, which messes with your melatonin production which goes hand in hand with your sleep cycle