Синхронное движение ProgressBar и TrackBar, движение в обратную сторону

Public Class Form4
    Private Sub Form4_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    End Sub
 
Private Sub TrackBar1_Scroll(sender As Object, e As EventArgs) Handles TrackBar1.Scroll
        ProgressBar1.Value = TrackBar1.Value
        Timer1.Enabled = True
    End Sub
 
    Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick
        ProgressBar1.Value += 1
        TrackBar1.Value += 1
        If ProgressBar1.Value >= 50 Or TrackBar1.Value >= 50 Then
            Timer1.Enabled = False
        End If
    End Sub

        ProgressBar1.Value -= 1
        TrackBar1.Value -= 1

Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick
        ProgressBar1.Value += k
        If ProgressBar1.Value >= 50 Then
            k = -1
        End If
        If ProgressBar1.Value <= 1 Then
            Timer1.Enabled = False
            k = 1
        End If
    End Sub