would this also work?
Use [my database]
alter database [my database] set recovery simple
--Backup LOG with NO_LOG
Use [my database]
BACKUP LOG [my database] WITH NO_LOG
--Shrink log files
Use [my database]
DBCC SHRINKFILE (1)
DBCC SHRINKFILE (2)
--Change recovery mode back to FULL
Use [my database]
alter database [my database] set recovery FULL
-- FULL database backup when completed