One time thread in libgdx after render loop starts

Is it possible to run a thread just after render method only once since render loop will call it in every iteration. This is my thread:

    new Thread(new Runnable() {
        float time=0;
        @Override
        public void run() {
            while(redPos<10) {
                time += Gdx.graphics.getDeltaTime();
                redPos+=(int)time;
            }
        }
    }).start();

I am not very much acquainted with threads so dont know proper way of doing it.
Please correct me if I am going wrong

Update: I got it working by shifting redPos increment to render method like this-

float time = 0;
void render(){
    if(redPos<10){
        time += Gdx.graphics.getDeltaTime();
        redPos+=(int)time;
    }
    batch.begin();
    batch.draw(ball, redPos, 5);
    batch.end();
}

Using Thread for animating sprite was a bad idea as it will be desynced with render thread.

You may wan't to avoid threads for this task. You can create a class that extends Sprite and write some code that changes the scale of the Sprite progressively in the draw method.

public class MySprite extends Sprite {


    private boolean doScale;
    private float   scaleBy;
    private float   scaleTime;
    private float   timeElapsed;
    private float   progress;
    private float   lastProgress;

    public MySprite(Texture texture) {
        super(texture);
    }

    public void scaleTo(float scaleTo, float time){
        scaleBy(scaleTo - getScaleX(),time);
    }

    public void scaleBy(float scaleBy, float time){
        this.scaleBy = scaleBy;
        doScale = true;
        scaleTime = time;
        timeElapsed = 0;
        lastProgress = 0;

        setOriginCenter();
    }

    @Override
    public void draw(Batch batch) {
        if(doScale){
            timeElapsed += Gdx.graphics.getDeltaTime();
            progress = timeElapsed/scaleTime;
            progress = progress > 1?1: progress;

            float progressDelta = progress - lastProgress;
            float scaleBy =  this.scaleBy *progressDelta;
            setScale(getScaleX()+scaleBy,getScaleY()+scaleBy);

            lastProgress = progress;

            if(progress == 1)
                doScale = false;
        }
        super.draw(batch);
    }
}

Then use the method scaleTo() or scaleBy() in MySprite...

    @Override
	public void create () {
        ...
        ...
        ...

		mySprite = new MySprite(texture);
		mySprite.scaleTo(2,1);//Scale to 200% in 1 seconds
	}

Although libGdx already provide Actions for this, you may want to consider the use of an Actor

    @Override
	public void create () {
        ...
        ...
        ...

        imageActor = new Image(texture);
		imageActor.addAction(Actions.scaleTo(2,2,1));//Scale to 200% in 1 seconds
	}