A recent article in the New York times shed some light on the toning controversy that currently exists. http://www.nytimes.com/2010/04/06/health/06real.html?src=me&ref=general  The author cites several academic studies that show that litfting higher weight for lower reps actually helped women increase muscle tone, while not adding bulk. The people who lifted the heavier weights for fewer reps also had a greater metabolism boost than those who did the lighter weights.  In a different study, the heavier weight and lower rep group also lost more body fat than the lighter weight, higher rep group. So consider this a busted myth!  While it is good to have some variety in weights and sets, if you want to see better results, be ready to incorporate different lifting styles.