Resistance training should be done two to three days per week. All major muscle groups should be trained including: chest, shoulders, upper and lower back, abdomen, hips, and legs. Do two to four sets to train each muscle group. Each set includes 8 to 12 repetitions of the exercise. A two to three minute rest interval between each set is reasonable.
Make sure to have at least 48 hours between resistance training sessions to allow muscles to recover. Resistance training devices include: free weights, machines with stacked weights, rubber bands, and using your own body weight to challenge your muscles.
Flexibility also known as stretching should be done two to three days per week for at least 10 minutes in duration focusing on the major muscle tendon groups of the body. Stretching should be done to the limits of discomfort (the point of mild tightness) within the range of motion, but no further. There are various types of stretching such as: static (holding the stretch), dynamic (ballistic, quick movements), and proprioceptive neuromuscular facilitation (PNF, partner needed).
Static stretching should be held for 15 to 60 seconds. Stretching improves range of motion and physical function which are important in countering the the loss of range of motion with aging.
All of these aspects to an exercise program will help achieve balance and you'll benefit even more when done on a regular basis. Make sure to contact an exercise professional, if you are beginning a workout program, to make sure you have the knowledge, skills, and abilities. Best of luck with your exercise program.
Sign up for a training plan.