Mr Lakshmanan finished the race in one hour, four minutes and 37 seconds - one second ahead of second-placed Md. Yunus.
Man Singh clocked one hour, four minutes and 40 seconds as the men's race witnessed a closely-contested fight.
Meanwhile, Monika timed one hour, 15 minutes and 34 seconds to be declared champion, while emerging runner Sanjeevani Jadhav was just a second late to be second.
She conceded that she was low on confidence coming to the competition as her training was not perfect.