Strength training can increase your muscle mass and this can happen at any age. Warm up before you start. You need to warm up to increase blood flow to your muscles. Do this by walking briskly, biking, or stair climbing for 5 to 10 minutes. Usually you will do between 10 and 15 repetitions.
Sets are groups of repetitions.
Ten to fifteen repetitions make up one set. Begin with one set of each exercise. As you progress in your program, you may want to increase to 2 sets. Rest your muscles for 48 hours between workouts. This allows the muscle to rebuild.