A Smith machine increases the safety and effectiveness of using a barbell with weights and is "ideal" for the home gym where people often workout alone, a blog has said.

Health and Fitness states that Smith machines use a metal frame to restrict the movement of a barbell to an up and down motion, which helps to guard against the bar accidentally dropping.

They can also be adjusted so that the barbell does not go lower than a certain point in order to protect its user from being injured or pinned in they lose their grip while working out.

The machines can be used for a range of exercises, including bench presses, overhead lifts and squat thrusts, the blog adds.

An alternative to the Smith system is the power cage, which the site says can be useful for people who do "plenty of barbell work without a spotter". Unlike Smith machines, their movement is not restricted and they can be used for exercises that use arcing movements.

Smith machines currently on the market include the Life Fitness Smith System and the Marcy SM4000.

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