My twin 4 year olds have recently started gymnastics...they seem to do bridges with ease and have started trying to do kickovers or back walk overs (not really sure what they are called, again I am NEW =) In a bridge and kick back over o do a handstand and fall forward into a bridge and kick back over....some people on this forum mentioned this was too young for their spines etc...have you heard this too? WHat age is it OK? How do I tell their coaches they shouldn't do this? THANKS for all help!