Standing is so Key to Bicycle Riding yet you would be surprised that the minute someone’s seat is taken away (i.e. on a bmx bike ) it is like we have never been on a bike before.
Standing lets us be explosive and use different muscles and positions that are essential to most types of cycling. Just watch a tour de france climb or sprint finish.
Watch any Mountain bike race . We need to be just as comfortable out of the saddle as in the saddle.