A doctor shares her muscle-building routine for longevity, from quick weightlifting workouts to daily protein

For Dr. Jennifer Timmons, building muscle isn’t just aesthetic; it’s a prescription for a long, healthy life for both herself and her clients.

Timmons, a board-certified longevity doctor in California, said muscle is essential for a healthy metabolism, protecting the bones and joints, and staving off illness and frailty as we age.

“The key to maintaining our independence is maintaining our muscle mass,” she told Business Insider. “Strong is the new goal. You could be skinny and still metabolically unhealthy.”

Timmons, 46, shared three pillars of her own routine for building lean muscle: time-efficient workouts, a high-protein and high-fiber…