Making an oxygen script with coroutines, anyone know why this isnt working?

char = game.Players.LocalPlayer.Character
hum = char.Humanoid

o = Instance.new('IntValue')
o.Name = "oxygen"
o.Parent = char
o.Value = 100

deplete = coroutine.create(function()
	while o.Value > 0 do
		wait(.5)
		o.Value = o.Value - 5	
	end
end)

restore = coroutine.create(function()
	while o.Value < 100 do
		wait(.5)
		o.Value = o.Value + 5
	end
end)

hum.StateChanged:connect(function(old,new)
	if new == Enum.HumanoidStateType.Swimming then
		print "im swimming"
		b = game.Lighting.Bubbles:Clone()
		b.Parent = char.Head
		if coroutine.status(restore) == "running" then
			coroutine.yield(restore)
			coroutine.resume(deplete)
		elseif coroutine.status(restore) ~= "running" then
			coroutine.resume(deplete)	
		end
	end
end)

hum.StateChanged:connect(function(old,new)
	if old == Enum.HumanoidStateType.Swimming then
		print "now im not"
		coroutine.yield(deplete)
		coroutine.resume(restore)
		if char.Head:FindFirstChild('Bubbles') then
			char.Head.Bubbles:Destroy()
		else
			print "well."
		end
	end
end)

It works in the water until I jump or get out, at which point both coroutines activate and the oxygen value flickers between two numbers. Anyone know why?

(This is my first time working with coroutines, if anyone has any tips or advice I'd appreciate it.)