High cpu usage

I have created one script and i have added it into cron to run after 10 mins. However I have noted that whenever that script runs, It causes CPU utilization of server to increase about 10-20 %
I have rechecked script and there is no way i can make changes, Script contain only 2-3 commands. So nothing can be done in script.
Is there any other way by which I can manage this CPU utlization,
Is there any way by which I can avoid/minimise this increase in CPU usage while running this script.