CEO Carl Daikeler compares metabolism to a furnace: Muscle is the coal and cardio stokes it, urging a balance of strength training and cardiovascular work.
https://www.foxnews.com/health/10-minute-fitness-habit-help-adults-over-40-maintain-muscle-stay-strong
https://www.foxnews.com/health/10-minute-fitness-habit-help-adults-over-40-maintain-muscle-stay-strong