I know one woman who has gotten amazingly cut doing slooooooooooooooow weight lifting moves with 1-2 lb dumbells. If I can recall where she talks about the technique I'll try and link it but it basically involves focusing and tightening the muscle as if you were lifting heavy weight, but using very very light weights or even no weight at all. It takes a lot of mental focus to contract the muscle without resistance.
MTA: because it is rare I dont have more to say
"When I got too tired to run anymore I just pretended I wasnt tired and kept running anyway" - my daughter Age 7