Aerobic exercises improve muscle increase muscular endurance.
Anaerobic improves muscles increase muscle strength.
There is not specific exercise, but if you want to gain mass in your muscles you have to be eating right. Certain types of foods to be able to gain that mass. Also you have to watch your calories simply to maintain your weights. You can do any kind of exercise, but the thing that will put mass in your muscles is the types of foods you eat to gain it.
Kaiser Permanente is covered under Medicare. Hoped this helped.