1. Low-repetition, high-resistance exercises iroduce power.

2. High-repetition, low-resistance exercises protiuce endurance.

3. Each of these two types of exercise is incapable of producing results obtained by the other.

4. Weakened, atrophied muscles should not be subjected to endurance-building exercises, until the muscle power has been restored to normal by power-building exercises.

5. Restoration of muscle power with return of motion in a limb has been neglected in the past. It is, in most instances, preferable to have a limited range of motion with good power than a normal range of motion with inadequate power.

6. Games and group exercises, as practised in reconditioning programs, are unsatisfactory for producing focal muscle development.

7. In order to obtain rapid hypertrophy in weakened, atrophied muscle, the muscle should be subjected to strenuous exercise and, at regular intervals, to the point of maximum exertion.

8. In cases of meniscectomies and unstable knees, quadriceps power should be obtained by the use of strenuous, non-weight-bearing exercises. Weight-bearing exercises can produce pain, thickening, and fluid in knees, which do not have adequate muscle support.