How do you change air friction?

So... I looked back into long-ago questions and I saw swimming in the air... and I made this LocalScript in StarterPlayerScripts.

wait()
local player = game:GetService("Players").LocalPlayer
wait(2)
spawn(function() while true do
    player.Character.Humanoid:ChangeState(Enum.HumanoidStateType.Swimming)
    game:GetService("RunService").RenderStepped:Wait()
end end)
player.Character.Humanoid:SetStateEnabled(Enum.HumanoidStateType.Swimming, true)
for i,v in pairs(Enum.HumanoidStateType:GetEnumItems()) do
    if v ~= Enum.HumanoidStateType.Swimming then
        player.Character.Humanoid:SetStateEnabled(v, false)
    end
end

wait()
spawn(function() while true do
    player.Character.Humanoid:ChangeState(Enum.HumanoidStateType.Swimming)
    game:GetService("RunService").RenderStepped:Wait()
end end)
wait()
spawn(function() while true do
    player.Character.Humanoid:ChangeState(Enum.HumanoidStateType.Swimming)
    game:GetService("RunService").RenderStepped:Wait()
end end)
wait()
spawn(function() while true do
    player.Character.Humanoid:ChangeState(Enum.HumanoidStateType.Swimming)
    game:GetService("RunService").RenderStepped:Wait()
end end)
for _, part in pairs(game:GetService("Players").LocalPlayer.Character:GetChildren()) do
    if part:IsA("BasePart") then
        local F = Instance.new("BodyForce", part)
        F.Force = Vector3.new(0, 196.2, 0) * part:GetMass()
    elseif part:IsA("Accoutrement") then
        local F = Instance.new("BodyForce", part.Handle)
        F.Force = Vector3.new(0, 196.2, 0) * part.Handle:GetMass()
    end
end--]]

The issue is, the BodyForces cause swimming in the air to be more like... well... swimming in the air; there's not enough friction.

How do I modify air friction here?

Response to answer:

I changed the code to this

wait()
local player = game:GetService("Players").LocalPlayer
player.Character.Humanoid.WalkSpeed = 20
wait(2)
spawn(function() while true do
    player.Character.Humanoid:ChangeState(Enum.HumanoidStateType.Swimming)
    game:GetService("RunService").RenderStepped:Wait()
end end)
player.Character.Humanoid:SetStateEnabled(Enum.HumanoidStateType.Swimming, true)
for i,v in pairs(Enum.HumanoidStateType:GetEnumItems()) do
    if v ~= Enum.HumanoidStateType.Swimming and v ~= Enum.HumanoidStateType.None then
        player.Character.Humanoid:SetStateEnabled(v, false)
    end
end

wait()
spawn(function() while true do
    player.Character.Humanoid:ChangeState(Enum.HumanoidStateType.Swimming)
    game:GetService("RunService").RenderStepped:Wait()
end end)
wait()
spawn(function() while true do
    player.Character.Humanoid:ChangeState(Enum.HumanoidStateType.Swimming)
    game:GetService("RunService").RenderStepped:Wait()
end end)
wait()
spawn(function() while true do
    player.Character.Humanoid:ChangeState(Enum.HumanoidStateType.Swimming)
    game:GetService("RunService").RenderStepped:Wait()
end end)

-- helper function so we can use a single bodyforce in rootpart 
-- instead of individual bodyforces per part
local function getSummedMass(model)
    local mass = 0 
    for _, v in pairs(model:GetDescendants()) do
        if v:IsA('BasePart') and v.ClassName ~= 'Terrain' then
            mass = mass + v:GetMass()
        elseif v:IsA("Accoutrement") then
            mass = mass + v.Handle:GetMass()
        end
    end

    return mass
end

-- in a loop, RenderStep recommended
while true do
    local rootPart = player.Character.HumanoidRootPart
    local force = Instance.new("BodyForce", rootPart)
    local mass = getSummedMass(player.Character)
    -- no need to convert mass to kg but for reference 1kg = 8000 rbx 
    local p = mass * 1.225
    local v = rootPart.Velocity
    -- a cube has a drag coefficient of 1.05 so we will use that
    local Cd = 1.05
    -- when air 'swimming' with top of head oriented with velocity there is an area of about 3 square studs
    local A = 3^2

    local DragForce = (.5 * p) * (v.Magnitude^2) * Cd * A

    local GravityOffset = Vector3.new(0, mass * workspace.Gravity, 0)

    local ActingForce = (v * DragForce) + GravityOffset

    force.Force = ActingForce
    game:GetService("RunService").RenderStepped:Wait()
end

However, it simply just poofs the whole character goodbye, and triggers a blackscreen. (as in, the character's parts and accessories/hats just go poof, and a never-ending blackscreen pops up, and the character doesn't recover)

So err....