Android delay loop to collect data from the gyroscope

I have been creating this android application, and have learned a lot about java and android programming along the way. However, I just haven't been able to figure out how to work time delay loops. I looked at other stack posts and saw different methods, but was not able to successfully implement them. I will describe what I want the loop to do.

When I touch the screen of the android app, I want the app to speak ("Begin testing"). For the next 20 seconds, I want the app to call angmag every 50 milliseconds so I can get the angular velocity's magnitude and see if it's above a certain threshold. This function is called every 50 milliseconds for 20 seconds, until the app speaks "testing complete" and then finish testing. How would I go about implementing this delay function in the android app? I've commented where I want to the delay in the code.

package com.example.shivamgandhi.gyrosafe;
    
import android.content.Intent;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.os.Handler;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Button;
import android.widget.RelativeLayout;
import android.widget.TextView;

public class Balance_Test_Activity extends VoiceControl implements View.OnClickListener, SensorEventListener, View.OnTouchListener {
    
  int n = 2;
  Button btnarray[] = new Button[n];
  private SensorManager sManager;
  private TextView textView79;
  RelativeLayout RelativeLayout;
  int count = 0;
  double arg0, arg1, arg2;

  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.balance_test);

    RelativeLayout = (RelativeLayout)findViewById(R.id.RelativeLayout4);

    btnarray[0] = (Button)findViewById(R.id.button10);
    btnarray[1] = (Button)findViewById(R.id.button20);

    sManager = (SensorManager) getSystemService(SENSOR_SERVICE);

    textView79 = (TextView)findViewById(R.id.textView79);

    for(int i = 0; i <n; i++){
        btnarray[i].setOnClickListener(this);
    }

    RelativeLayout.setOnTouchListener(this);
  }

  //when this Activity starts
  @Override
  protected void onResume()
  {
    super.onResume();
    /*register the sensor listener to listen to the gyroscope sensor, use the
    callbacks defined in this class, and gather the sensor information as quick
    as possible*/
    sManager.registerListener(this, sManager.getDefaultSensor(Sensor.TYPE_ORIENTATION), SensorManager.SENSOR_DELAY_FASTEST);
  }

  @Override
  protected void onStop()
  {
    //unregister the sensor listener
    sManager.unregisterListener(this);
    super.onStop();
  }

  @Override
  public void onClick(View v){
    if(v == findViewById(R.id.button10)){
      Intent myIntent = new Intent(this, Results_Page_Activity.class);
      startActivity(myIntent);
    }

    if(v == findViewById(R.id.button20)){
      //implement
      int gyro_results = gyrotest();
    }
  }

  @Override
  public boolean onTouch(View v, MotionEvent event){
    if(v == RelativeLayout && count ==0 ){
      gyrotest();
      count = 1;
      return true;
    }
    else{
      return false;
    }
  }

  public int gyrotest(){

    int gyro_results = 0;

    speakWords("Please place your hands on your hips and keep your feet under your shoulders. Hold your balance for the next 20 seconds");

    Thread.sleep(5000); //delay 5 seconds;
    int count = 0;
    int angmag = 0;
    while(count < 401){
      if (Math.sqrt((arg0*arg0 + arg1*arg1 + arg2*arg2)) > 20){
        angmag = 1;
      }
      else{
        angmag = 0;
      }

      gyro_results = angmag + gyro_results;
      count++;
      Thread.sleep(50000);
    }

    return gyro_results;
  }

  @Override
  public void onAccuracyChanged(Sensor arg0, int arg1)
  {
    //Do nothing.
  }


  public void onSensorChanged(SensorEvent event)
  {
    //if sensor is unreliable, return void
    if (event.accuracy == SensorManager.SENSOR_STATUS_UNRELIABLE)
    {
        return;
    }

    arg0 = event.values[0];
    arg1 = event.values[1];
    arg2 = event.values[2];

    //else it will output the Roll, Pitch and Yawn values
    textView79.setText("Orientation X (Roll) :"+ Float.toString(event.values[2]) +"\n"+
            "Orientation Y (Pitch) :"+ Float.toString(event.values[1]) +"\n"+
            "Orientation Z (Yaw) :"+ Float.toString(event.values[0]));
  }
}

I am assuming the code should look something like this:

delay 5 seconds;
int count = 0;
while count < 401{
    gyro_results = angmag + gyro_results;
    count++;
    delay 50 milliseconds;
}

return gyro_results;

I wish I were able to figure out how to code this on my own, but I've tried most methods.

Edit: added in modified code with Thread.sleep function. However, I'm still seeing some issues with Thread.sleep.

Used sleep() method in Thread for delay process.

try
{
Thread.sleep(5000);    //delay 5 seconds;
int count = 0;
while count < 401{
gyro_results = angmag + gyro_results;
count++;
Thread.sleep(50000);    //delay 50 milliseconds
}
}catch(InterruptedException ie)
{
//Log message if required.
}