This is very odd but it is Sade "Hang on to Your Love".
This is odd first and foremost because Sade is hardly known for hardcore workout songs. But, there is a line in the song that states,
"Be brave when the journey is rough,
Its not easy when youre in love.
Dont be ashamed when the going gets tough
Its not easy,
Dont give up.
If want it to get stronger youd better not let go.
You got to hold on longer if you want you love to grow."
Now although this song is primarily about love it deals with the theme of persitence and perserverence, which I translate to the my lfting routine. The line in the song "If want it to get stronger youd better not let go.
You got to hold on longer if you want you love to grow." always gives me a boost if I hear it towards the end of my set. Also a winner is "Can't Stop" by The Red Hot Chilli Peppers".