At the starting line as Lakitu holds the traffic light, don't be too hasty with holding the accelerate button.
Try to select a car that has 3 Nitros already in the tank and get a good jump off the starting line.
After the dribbler shoots the ball, have him run straight back to the starting line and tag the next person.
Again, any list of the best abdominal exercises will vary a little by the person you ask, but here's a good starting line for anyone looking to get in shape.