When you're building a fast-paced action game or a survival sim, a roblox custom stamina system script is usually one of the first things on your to-do list. Let's be real: the default Roblox movement is a bit too "infinite" for most competitive or immersive games. If your players can sprint across the entire map without ever catching their breath, you lose that sense of tension and strategy. By adding a custom stamina bar, you're forcing players to make choices. Do they sprint now to dodge an attack, or do they save that energy for a quick getaway later?
Setting this up isn't nearly as intimidating as it sounds. You don't need to be a Luau math wizard to get a working prototype going. Most of the time, it's just about managing a few variables and making sure your UI talks to your logic. In this guide, we're going to break down how to create a system that feels smooth, looks good, and—most importantly—doesn't break the second a player hits the Shift key.
Why You Shouldn't Use a Simple "While" Loop
If you've spent any time looking at old tutorials, you might see people using while true do wait(0.1). Honestly? Don't do that. It's clunky and can lead to some really jittery movement if your game starts lagging even a little bit. Instead, we want to use RunService.Heartbeat. This runs every single frame, which makes the stamina drain and regeneration look buttery smooth.
When we talk about a roblox custom stamina system script, we're looking for responsiveness. If a player lets go of the shift key, the bar should start regenerating almost instantly, and the character should slow down right away. If there's even a half-second delay, it feels like the game is "heavy" or unresponsive, which is a death sentence for an obby or a combat game.
Setting Up the Variables
Before we even touch a script, we need to think about what "stamina" actually means for your game. You need a few core values: * MaxStamina: Usually 100, but you could make this upgradeable. * CurrentStamina: This starts at 100 and moves up and down. * DrainRate: How fast does it go down? * RegenRate: How fast does it come back? * SprintSpeed: How fast the player moves when sprinting. * WalkSpeed: The normal speed (usually 16).
I like to keep these at the top of my script so I can tweak them easily later without digging through fifty lines of code.
The Core Logic: A Basic Script Template
Let's look at a practical way to set this up. You'll want to place this in a LocalScript inside StarterPlayerScripts (or StarterCharacterScripts). We're focusing on the client side here because movement on Roblox is handled by the player's computer to keep things feeling snappy.
```lua local UIS = game:GetService("UserInputService") local RunService = game:GetService("RunService") local Players = game:GetService("Players")
local player = Players.LocalPlayer local character = player.Character or player.CharacterAdded:Wait() local humanoid = character:WaitForChild("Humanoid")
-- Configuration local MAX_STAMINA = 100 local currentStamina = MAX_STAMINA local sprintSpeed = 25 local walkSpeed = 16 local drainAmount = 0.5 -- Per frame/step local regenAmount = 0.3 local isSprinting = false
-- This detects when the player presses Shift UIS.InputBegan:Connect(function(input, processed) if processed then return end if input.KeyCode == Enum.KeyCode.LeftShift then isSprinting = true end end)
-- This detects when the player lets go UIS.InputEnded:Connect(function(input) if input.KeyCode == Enum.KeyCode.LeftShift then isSprinting = false end end)
-- The heart of the system RunService.Heartbeat:Connect(function() -- Check if the player is actually moving while sprinting local isMoving = humanoid.MoveDirection.Magnitude > 0
if isSprinting and isMoving and currentStamina > 0 then humanoid.WalkSpeed = sprintSpeed currentStamina = math.max(0, currentStamina - drainAmount) else humanoid.WalkSpeed = walkSpeed if currentStamina < MAX_STAMINA then currentStamina = math.min(MAX_STAMINA, currentStamina + regenAmount) end end -- Here is where you would update your UI bar! -- print("Current Stamina: " .. math.floor(currentStamina)) end) ```
Making the UI Look Professional
A roblox custom stamina system script is nothing without a visual indicator. Sure, you could just look at the numbers, but your players need a bar.
Don't just change the size of the bar instantly. Use TweenService. If the stamina drops, you want that bar to slide down smoothly. If it hits zero, maybe you want the bar to flash red. It's these tiny little visual cues that make a game feel "premium" rather than just a weekend project.
When the stamina hits zero, you should also implement a "fatigue" state. Instead of just letting the player immediately start sprinting again the second they have 1 point of stamina, maybe force them to wait until the bar is at least 20% full. This prevents that weird "stutter-stepping" where players spam the shift key to move slightly faster while exhausted.
Handling the "Exhaustion" State
To add a bit more depth, you can create a boolean variable called isExhausted. If currentStamina reaches 0, set isExhausted to true. While this is true, the player cannot sprint. They have to wait for the stamina to regenerate to a certain threshold (let's say 25) before isExhausted becomes false again.
This adds a layer of strategy. If a player pushes themselves to the absolute limit, they pay a bigger penalty than someone who manages their energy levels wisely. It's a small change in the script, but a huge change in how the game feels to play.
Optimization and Cleanliness
One thing people often forget is what happens when the player dies. Since the script is likely in StarterPlayerScripts, you need to make sure it re-connects to the new character every time they respawn. Using player.CharacterAdded:Connect() is the way to go here. If you don't, the script will keep trying to change the WalkSpeed of a character model that doesn't exist anymore, and your output log will be a sea of red errors.
Also, think about mobile players! Not everyone has a Shift key. If you want your roblox custom stamina system script to be inclusive, you should probably add a GUI button for mobile users or use ContextActionService to create a virtual "Sprint" button that appears automatically on touch devices.
Security Considerations
Since this is a LocalScript, a dedicated exploiter could technically change their WalkSpeed or give themselves infinite stamina. This is the "Client-Server" dilemma. For most casual games, a client-side script is fine. But if you're making a serious competitive game, you'll want a server-side check.
The server should occasionally check the player's speed. If they are moving at 25 studs per second for 30 seconds straight without their "server-side stamina" value decreasing, you know something is up. You don't need to run the UI logic on the server, just a simple background check to keep things fair.
Final Touches
To really sell the effect, add some sound. A quick "heavy breathing" audio track that triggers when stamina is below 15% adds a ton of atmosphere. You could even add a slight camera shake or a FOV (Field of View) increase when sprinting to make it feel like the player is actually gaining momentum.
Creating a roblox custom stamina system script is really about the experience, not just the code. It's about limiting the player in a way that makes the game more fun, not more frustrating. Once you get the hang of the RunService and UserInputService combo, you can apply that logic to all sorts of things—mana for magic spells, oxygen for swimming, or even fuel for a vehicle.
Take the script above, throw it into a project, and start messing with the numbers. Change the drain rate, make the regen slow, or try making the player walk even slower than usual when they run out of breath. That's the best way to learn!