void Start(){
	initPosition = gameObject.transform.position;
	rb = gameObject.GetComponent<Rigidbody>();
	distanceText = distanceTextObject.GetComponent<Text>();
	highScoreText = highScoreTextObject.GetComponent<Text>();

	// DistanceTextとHighScoreTextの初期値をセット
	SetDistanceText(0f);
	SetHighScoreText(0f);
}