big mare filling out - and feeling good = a very forward horse, help please!

[cobface]

My 5yo TB is always a very poor doer, but recently shes put the weight on and looks like a different horse! (will upload some before and afters tomorrow) shes starting to develop a neck and is really filling out and looks like she now has alot of bone, she looked scrawny a few months back but shes really changing. Shes been a lot better in the school, very forward and willing and now accepts the contact. However i took her out the other day on her own and she was very forward to the point where she actually knocked my confidence a bit as she seemed so full of herself. I am taking her out again in the morning but cant help but feel a bit nervous as shes no fun when shes nuts!!! (think loads of rearing and HUGE flying bucks) as we have seen when shes eaten the wrong things...........now am worried that now shes up to weight and getting fitter that shes going to turn into a loon!!! I have had her a year now and its the first time that shes holding weight. Shes fantastic at jumping and in the school, but i don't want her mad out hacking!!

So has anyone ever had a horse thats put the weight on and proven too much?? even after a year?

 

[tinkandlily]

Have you checked her feed?I have two tbs and my younger one is the same, she was very scrawny and easy to do but now shes grown two hands, filled out and got fitter. I tend to turn mine out first while i do the stables then if she's still full of beans i'll lunge her. I could be your horse needs a good gallop, if you don't want to, can someone else do it for you, i don't do this with my younger mare as she has recently had foot problems, but i do this very regularly with my older mare and i can get straight on with no probs. I have also done this with my friends horse who was a handful in canter because he just wanted to go, but she was not confident to do it, so i did and he's as good as gold.