Coroutines Solution to Running faster and faster

--[[
    This script uses coroutines and pauses acceleration and resets when the humanoid stops moivng.
--]]

local player = game.Players.LocalPlayer
local hum = player.Character:WaitForChild("Humanoid")

local WALK_SPEED = 16 -- Beginning walk speed
local INCREASE = 0.5 -- How much it accelerates each time
local INTERVAL = 0.1

local isRunning = false -- Whether the humanoid is running

local accelerate = coroutine.create(function()
    while wait(INTERVAL) do
        if hum.MoveDirection == Vector3.new() then -- if the humanoid is not moving
            isRunning = false
            hum.WalkSpeed = WALK_SPEED -- reset walk speed
            coroutine.yield() -- Pause until the player starts running again.
        end
        hum.WalkSpeed = hum.WalkSpeed + INCREASE
    end
end)

hum.Running:Connect(function(speed)
    if speed > 0 and not isRunning then -- When the player is just starting to run
        isRunning = true
        coroutine.resume(accelerate)
    end
end)