Weight training is often a neglected form of exercise. Some think weight training is only for muscle heads, but they are wrong from a general health standpoint,. Only about 23% of those over 45 get in adequate strength training.
Studies show you may be missing out on the most important aspect. Strength training reduced premature death by 23% and cancer by 31%! Longer life is just 1 aspect of the benefit.
Strength training benefits your cardiovascular system, decrease your risk for osteoporosis, improves mood, and self-esteem, sleep quality, and blood sugar control.
This is not to eliminate aerobic training which has positive benefits on brain function, cardiovascular fitness, endurance and stamina. Studies showing life prolongation are sparse and cancer protection absent.
In my opinion, a good balance of aerobic, strength training and flexibility is best.