This trainer specializes in helping women over 40 build muscle and mobility—here’s her favorite 20-minute dumbbell workout for beginners

Woman performing a squat while holding dumbbells, in a domestic setting.

Thankfully, the notion that you are over the hill once you hit 40 has gone out of fashion.

This decade can bring plenty of positives, but one downside is a gradual loss of muscle mass, which affects everything from your metabolism to your mobility and strength.