Middle-aged and elderly people prefer aerobic exercise over strength training for several reasons. Firstly, aerobic exercises like walking and jogging put less stress on the joints and have a lower risk of injury. Secondly, many people in this age group are not fully aware of the benefits of strength training and believe it is only for younger people. In fact, strength training is very important for older adults as it helps increase bone density and prevent osteoporosis. Additionally, aerobic exercises are easier to maintain, and many find them more enjoyable. Overall, combining aerobic exercise with strength training can provide comprehensive health benefits for older adults.