"I know I should give my body a day of rest after toning, but if I want to do squats, push-ups and sit-ups between toning days would that be okay?" --pt40

Recovery is important because many of the benefits and results you earn from weight training take place during this time. I recommend waiting 48 hours between weight training sessions when you've pushed yourself to failure in six to 15 repetitions. The idea is to push yourself hard enough during the weight training session that you actually do need to recover. On the other hand, doing calisthenics and exercises where you lift your own body weight (like push-ups and squats) is an acceptable way to actively recover as long as the level of intensity is "somewhat easy" to "moderate." Your muscles should not burn or feel uncomfortable on recovery days. The most valuable lesson I have learned in my training is that if you really want to change the shape of an area then you have to give it a break. My motto: work hard -- rest hard.