Then, push the weight back upward, but keep a slight bend in your knees as you reach the top to keep tension on the muscle. (justinkavanaghfitness.com)
For metabolic stress, use exercises that put a lot of tension on the muscle in it's shortest position — barbell curls, lateral raise and leg extensions. (theathleticbuild.com)
All my resistance training is performed relatively slowly while trying to keep continuous tension on the muscles at all times. (fitnesscontrarian.com)