Sensation of needing to urinate when jumping?

Factual Questions
1

My sister started a “Boot Camp” fitness program this morning and noticed that when doing jumping jacks or other explosive movements, she felt like she was going to pee her pants. She did say that she had just gone and shouldn’t need to go again.

I suggested she should work on her kegel muscles (she is a mother of three), but she pooh-poohed me and asked me to post it here.

Another girl from the same class said she had the same feeling. The both drink coffee, if that makes a difference.

Any thoughts dopers?

2

Well, maybe she actually needed to pee? I don’t know about other coffee drinkers, but when I wake up in the morning, my bladder’s pretty distended; after a couple of years of this, it takes quite a volume of urine before I start realizing I need to pee.

Or perhaps the various suspensory ligaments and whatnot are a little weak and being jostled by the jumping-jacks.