I'm sure the young woman cyclist (probably in her 20's or early 30's), was cheekily just showing off abit:

Today she and I were both cycling in a separate cycle track downtown in light car traffic. At red traffic light, she balanced trackstanding on her bike (which had a few gears, not just a fixie), then dropped left hand off her handlebar and reached in her knapsack side pocket for her iPhone. While still trackstanding and hanging onto bike on only 1 handlebar, she was scrolling up and down her thumb on the iPhone screen with left hand.

I noticed she carried 2 small hula hoops on her knapsack that looked acrobatic, colourful ....a clue that maybe she was already athletic in another sport. She was small under 5 ft. and petite with strong leg muscles.

For once, I thought it was fun she showed off abit. You don't see women commuters showing off lightly in that way. Excellent balance.

The traffic light was over 1 min. long.