How do I stop all character animations?

Hey! I'd like to stop an animation but I don't know how to stop it.

I know that you can do variable:Stop() but the problem is.... I can't tag the variable!

Why?

I've made a KeyDown event and a KeyUp event. I wanted to make the script play an animation at keydown and stop it at keyup but I have no idea how to access the animation ! :(

The variables:

plr = script.Parent.Parent

char = plr.Character

torso = char:findFirstChild("Torso")

	

mouse = plr:GetMouse()

The Keydown script:

if key == "f" then
			if plr.LEVEL.Value >= 3000 then
			game:GetService("Chat"):Chat(plr.Character.Head, "Hado 33: Sokatsui!")
				
				-- Animation ( Charge )
				
				animation = script.animationpackage.kido:WaitForChild("hado33charge")
				local animationTrack = char.Humanoid:LoadAnimation(animation)	
				animationTrack:Play()
				
				-- Effects
				
				torso.Anchored = true
				blueflame = Instance.new("Part", game.Workspace)
				blueflame.Anchored = true
				blueflame.Shape = "Ball"
				blueflame.BrickColor = BrickColor.new("Bright blue")
				blueflame.Transparency = 0.4
				blueflame.Size = Vector3.new(1,1,1)
				blueflame.TopSurface = "Smooth"
				blueflame.BottomSurface = "Smooth"
				blueflame.CFrame = torso.CFrame * CFrame.new(1.6, .25, -1.4)
				fire = Instance.new("Fire", blueflame)
				fire.Color = Color3.new(0,0,128)
				
				
				-- End of Effects
			else
				game:GetService("Chat"):Chat(plr.Character.Head, "I'm not strong enough to use this Hado...")
			end
		end

and the KeyUp script(unfinished):

function onKeyUp(key)
		if key:byte() == 32 then
			char.Torso.BodyVelocity:Destroy()
		elseif key == "j" then
			game.Workspace[plr.Name .. "dankuwall"]:Destroy()
			char.Torso.Anchored = false
		elseif key == "f" then
			animationTrack:Stop()
		end
	end -- onKeyUp



mouse.KeyUp:connect(onKeyUp)
mouse.KeyDown:connect(onKeyDown)

I hope I've given you enough information.