I'd rather my child trained for being an athelete

Toddlers love tumbling around, kicking and punching, I think gymnastics, swimming and karate would be
more suitable to them than playing a musical instrument, sitting tight with a piano or holding a violin.
I can't imagine my three year old sitting down on a bench for over 20 minutes. Not possible even for a four year old.
Playing sports is healthier and more enjoyable for young children as active as mine.