Recent studies have showed that people who were on a diet and did aerobic exercise (even just walking) were more likely to lose muscle than if they did no exercise at all.
Dieters who did weight training often lost more fat than those who dieted alone, and did not lose as much muscle as those who dieted and did aerobic exercise.
Losing muscle can lead to loss of strength and stability which can lead to falls.
Strength training doesn’t have to involve an expensive gym membership. Using resistance bands or lifting cans found in your pantry can be enough to keep muscles active and healthy.