foreach my $worksheet_num ( 1 .. 5 ) {
    my $worksheet  = $workbook1->Worksheets($worksheet_num);
    $worksheet->Cells($Row, $Col)->{'Value'} = $var1;
    $worksheet->Cells($Row, $Col+1)->{'Value'} = $var2;
    $worksheet->Cells($Row, $Col+2)->{'Value'} = $var3;
    $worksheet->Cells($Row, $Col+3)->{'Value'} = $var4;
}