How can I get her in better shape...

I want gypsy to be in better shape, I mean she looks good now but her mucle tone isnt what it could be. I know about lunging in side reins to help with her back and hind quarters. I was taking her up to the galloping hill and she was getting a good work out and having fun but now its all rainy and im not sure about cantering with the grass wet. What are fun ways to get a good workout with out having to just walk, trot, canter in the ol arena?

Try getting her collected so that she works more from her hindquarters. This should improve her muscles in many areas, not just her hindquarters.

A good groom is vital for muscle tone Also, when you are hacking it makes a HUGE difference walking fast and just collecting up while you trot so they are working the muscles

Ride a lot of transitions, and ride them correctly. Your horse should move forward even into downwards transitions. Ride serpentines, loops, circles, spirals, and zigzags. Make your horse bend around your leg. It's not something you get overnight - it takes a long time (especially if your horse is out of shape). If your horse isn't balanced, forward, and already somewhat muscled, you won't be able to collect properly, so collecting your horse probably won't help you build muscle.

Moomoo I can't groom, she hates it! Im only able to use a gelly curry and its very softly other wise she will cringe,bite,threaten to kick..ect.

I try and have her collected but it is hard for us... I do a lot of the figure eights, circles,..ect. But not a lot of transitions so ill work on those!

Any other suggestions?

Oh yah, do any of you go out and ride in the wet grass? Is it safe? Lol can you at least canter in it?

I wouldn't ride in wet grass, it's one of the most slippery things you can ride on! Plus it will chew up the grass and ruin it.

To get collection your horse needs to be forward, straight, balanced, and carrying herself. If you are trying to collect without these things, you're probably just moving slower and with her head "set" rather than true collection.

Here is a video of me riding her... I just can't seem to get her collected, does she seem off? Or unbalanced? Every time I ask for her to be collected she just pops her head back up and then I have to ask again and its just been the same thing. And then when she is collected she will invade the bit and stretch her head down. And I have lunged her in the side reins to help with this but it hasnt... I also try to keep my hands steady so I dunno.

Maybe try some draw reins, then they can't pop their head back up, you only need to use them for a few days then move on from there

Arnt they the same as side reins?

No, side reins tie their head in where as draw reins draw their head in.
Well, draw reins go from your hands, through the bit rings then between your horses legs and attach to the girth. You pull, then your horses head goes in, but you need someone on the ground telling you when their head is in the right place. Also with draw reins they can't lean on you :) I have no idea if that made sense, its midnight, lol