It is a must in your weight lifting routines to change things up. Most of us tend to stick to workout routines that are comfortable and that we are good at. Every couple of weeks you should be changing up your routines by varying your strength training exercises as well as using different fitness equipment. Getting a personal trainer to help you learn new exercises will help to push your fitness level to new hieghts. Don't always think of weight training with actual weights or machines. Anything that adds resistance to a movement such as resistance bands is considered weight.
Weight lifting is a form of resistance training and this type of training is critical to keeping your body in good shape. Weight lifting helps to keep your muscle mass on in turn keeping your metabolism up. As we age our muscle mass decreases and our metabolism decreases, good workout routines are exactly what you need to keep this from happening.