I imagine that as long as you continue to lift weights & challenge yourself to lift heavier, you should maintain the gain forever. If you go back to lighter weights when doing other workouts, you'll eventually lose your gains. I keep my weight sheets for all Cathe's weight DVDS to challenge myself to increase the weights used. HTHHow long does the 5 percent gain last? Will you gain 5 percent each time you complete all the Mesocycles?