Actually Keiko heavy weights with low reps IS the way to train if you don't want to gain mass yet want to be strong and hard. This is the way most athletes train that don't want to go up into the next weight class. I'd suggest reps no higher than 6 with a weight that you can do 7-8 times. You never want to go to failure in this rep range. This usually equates to 80% of your 1RM though I find it easier to say do a weight for 6 reps that you can get 7 with.
Use this rep and set scheme with compound movements and you should get what you're looking for. I've noticed a difference since adopting similar training.
Use this rep and set scheme with compound movements and you should get what you're looking for. I've noticed a difference since adopting similar training.