I used to have a personal trainer whom Luis Carruthers had recommended but he came on to me last fall and I decided to develop my own fitness program which incorporates both aerobic exercises and training. With weights I alternate between free weights and weight machines that use hydraulic, pneumatic or electromechanical resistance. Most of the machines are very efficient since computerized keypads allow one to make adjustments in weight resistance without getting up. The positive aspects of the machines include minimizing muscle soreness and reducing any chance of injury. But I also like the versatility and freedom that free weights offer and the many variations in lifting that I can’t get on the machines.