I think with gymnastics, you have got to be dedicated because it is only going to get one hell of a lot worse yet.
DD1 (9) does 18 hours a week term time and more in the holidays. That's three school nights and both mornings at the weekend. On top of that, she dances (1 hour group lesson, half hour private lesson) and learns the flute (in school).
DD2 (6) does 8.5 hours of gym, 1.5 hours of dancing and learns the violin (again in school).
Thankfully, DD2s gym classes fit within DD1s.
Sometimes I hate it. Especially over the summer when she was doing 24 hours a week. I felt it ruined my summer tbh. But DD is extremely committed to it, and it is her passion, her reason for living. DD2 knows no different. I think you have to embrace the hours or you do end up resenting it. I have met a great bunch of mums through gymnastics, and we often go for coffee together when the girls are training, did playdates in the summer and so on.
If your daughter is coping fine, then I'd continue as normal. As your daughter progresses and the gymnastics become more consuming and more dangerous, I think it is good for them to have a hobby that is just for fun. DD has to work at gym. Its hard and she makes a lot of sacrifices for it. If she didn't have her dancing, she wouldn't have anything that she just did for fun. I also think that as gym gets more complex, it becomes more dangerous (DD is currently recovering from a fracture she really sustained in gym) I'm conscious that they're only ever one nasty fall away from their gym life being over. If my DD only had the gym, and she couldn't do that because of a nasty fall (and believe me, I've seen a few really nasty falls at comps etc) then that would be her whole life over. At least by letting DD have a second hobby just for fun, she'd have something to fall back on if that happened. Although, I've always thought this, my DD had her second fracture this year. We may be coming to a point when she has to make choices about her gymnastics. I am glad that if she ever has to choose not to do it competitively anymore, she has got a life outside of the gym.
Oh, and her height / weight thing is perfectly fine. she has a six pack to die for, and really chunky shoulders, but she is by no means underweight. Most of her gym friends are the same. They're not big girls, but they're not starved either.
Sorry, for the long post but the last thing I'd say is that you really have to get a tough skin and ignore the people outside of the gym world. I've had lots of mums criticise me for my DDs gym hours, making snidey remarks like I'm some kind of pushy mother. I actually don't mind whether she does gym or not. I'd be quite happy if she gave up. Its DD who wants to do it, not me. People in the gym world understand the hours, the commitment etc. But because it is such a young girls sport and so hard to learn the tricks, the hours have to be intense. People outside of gym often think that your daughter is just doing a few handstands and maybe a cartwheel (I know people think that of my daughter!) They just don't get it, and you have to accept that.
Sorry, that was a bit of a ramble
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