Machines vs free weights: which should you use?

Some lifters treat machines as cheating; others never leave them. Both camps are missing out. Machines and free weights build muscle about equally well when you train them hard. They differ in what else they give you, and the best plans use each for what it does best.

What free weights do best

• Heavy strength. Barbell squats, deadlifts and presses let you load the most weight and build whole-body strength.
• Balance and coordination. Stabilising the weight trains the small muscles that machines do for you.
• Anywhere use. Dumbbells and a bar work at home, in a hotel or in any gym.

• Back squatQuads, Glutes
• DeadliftHamstrings, Glutes, Lower back
• Barbell bench pressChest
• Standing overhead pressFront delts
• One-arm dumbbell rowLats, Upper back
• Goblet squatQuads, Glutes

What machines do best

• Learning safely. A fixed path lets beginners push hard without worrying about technique or a spotter.
• Isolating a muscle. Leg extensions, leg curls and pec decks hit one muscle without the rest of your body tiring first.
• Training hard when tired. Late in a workout, or around an injury, a machine lets you get close to failure safely.

• Leg pressQuads, Glutes
• Lat pulldownLats
• Machine chest pressChest
• Seated leg curlHamstrings
• Leg extensionQuads
• Assisted pull-up machineLats

What the research says

Studies comparing machine and free-weight training (for example, Schwanbeck and colleagues, 2020, on squats and leg presses) found similar muscle growth. Free weights tend to win when strength is tested with free weights, and machines when it's tested on machines: you get best at what you practise.

How to combine them

1. Start each workout with a free-weight compound lift while you're fresh.
2. Follow with machines and cables for extra sets on the muscles you want to grow.
3. Swap freely when you need to. A busy rack, a sore back or a crowded gym is a reason to pick the machine, not to skip the muscle. See training around an injury.

Liftsmith does this for you. It plans from the equipment your gym actually has, puts the big lifts first, fills the rest with machines and cables, and offers a one-tap swap when something is taken.