Kate Ligler, MINDBODY Wellness Manager and NASM-certified personal trainer, corrective exercise specialist, and performance enhancement specialist, told POPSUGAR that if you are somebody who is already very lean and you're really looking to target your muscles more, a machine is going to be effective. But, she said, free weights will give you a full-body approach that machines won't necessarily give.
Kate continued, "By and large, when it comes to toning, machines can miss that total-body component that using free weights will. For instance, a standing bicep curl also engages your core. . . . If you are somebody who is targeting weight loss, I would recommend a free weight over a machine any day of the week because you're going to burn more calories and ultimately target more systems."