What Is the Difference Between Weight Machines and Free Weights?

It’s been called The Greatest Disagreement of Our Time, the Great Debate, the Raging Confrontation, and the Arnold Paradigm Shift[1]. Today we’re talking about Free Weights and Weight Machines. The Good, the Bad, the Ugly, and the Questionable. Lets get to it!

What falls into each category?

Free Weights are resistance training tools that allow the body to move through a full range of motion at any given joint. They do not provide any structural support to a given movement. The body must provide both the Power necessary to move the weight as well as the Form to keep the weight moving through the correct path of travel. A few examples of this include barbells, dumbbells, kettlebells, and medicine balls.

Weight Machines are also resistance training tools, but they usually provide structural support to the body during an exercise. Most machines will support 1-5 different exercises when used correctly[2], and the exercises will all be related. Machines differ from free weights most notably in that they provide a significant assistance to the Form of an exercise, while the body provides the Power. An example would be the squat machine or leg press machine, both of which usually support squat-like motions and calf raises.

Free Weight Pro’s and Con’s

Free Weights force the body to be responsible for both Form and Power, providing several benefits and some drawbacks.

Good Stuff:

Better Recruitment of Muscle Groups

According to a study conducted by McCaw and Friday at the Biomechanics Laborartory of Illinois State University, subjects showed greater muscle recruitment during a free weight bench press as compared to a machine bench press at similar weights.[3] You literally work harder to do the same move, as your body recruits more muscles to assist in the Form of the exercise. In theory this also means you will get stronger, faster as you do more work every repetition.

Increased Proprioception

Proprioception is your ability to understand and reference the position and angle of one body part in relation to other body parts, as well as your position in space. More simply: you know where your limbs and junk are in comparison to one another and to stuff around you. When you force the body to control the Form of a movement with free weights, you are also learning how your body parts react to one another in different positions. This improves your muscle memory for those relations, and makes you move better. You see increases in balance and coordination as a result.

Increased Exercise Efficiency

Again, because we recruit more muscle groups when using free weights, it means individual exercises are more efficient at burning calories and building strength. Every movement is just plan more work, and work is what makes you stronger. When you recruit one major muscle group and it’s stabilizer muscles, you are doing a Free Weight Isolation exercise. The standing barbell curl is a good example of isolating the biceps as your primary mover, with the abs, triceps, forearms, and others acting as stabilizer muscle groups. With machine curls, you would lose most of that ancillary muscle activation, necessitating additional work to improve those other muscles later.

In addition, many free weight movements are Compound Exercises, which work more than one major muscle group as well as all the stabilizer muscles supporting both. A good example is the squat (weighted or not), which uses the quadriceps as the primary mover, but also recruits the calves, glutes, hamstrings, and lower back muscles. These are basically all major muscle groups, causing the squat to hit almost everything from the belly button down. The more work each exercise makes you do, the fewer exercises you have to do overall!

Greater Range of Motion

Your body can move in all sorts of ways. Movement patterns are controlled by your joints, with each joint having both Type and Path which ultimately account for Form. Your knees and elbows are Hinge type joints, able to follow about 150° of freedom from extended/locked out, to fully flexed/bent. In contrast your shoulders and hips are Spheroidal (Ball and Socket) joints, allowing almost 180° of freedom in almost any direction.

Free weights allow you to move through the entire range of motion for any given joint, which means you never have to truncate or fall short of working the muscles at every angle. A benefit is that your movements will be just as strong at the extreme angles as they will right in the middle of a movement. For example, if an assisted pull-up machine were to stop your short of going down to “dead hang” where your elbows lock out, it would stop you from building the power to pull from locked elbows to flexion, reducing exercise efficacy.

Bad Stuff

Increased Risk

Whenever you can move more, you increase the risk associated with that movement. Standing is riskier than sitting, running is riskier than standing, and so on. The same applies with free weights. You’re able to do more, which means you’re able to make more mistakes. This is easily mitigated by working with a trainer, coach, or skilled partner, but it does take time to learn and reduce the risks accordingly.

Slower Workouts

There are two types of free weights you can use: Adjustable weights allow you to increase of decrease the resistance by changing out weight plates on the same bar, while Preset weights cannot be adjusted so you need an entire set to cover multiple resistance levels. Adjustable weights need to have weights changed out between movements, which takes time. The Preset weights don’t need to be adjusted, but they’re usually available in commercial gyms, so you might need to wait for someone else to finish with the weight you need. Time is increased either way.

Steeper Learning Curve

The best free weight movements take time and coaching to really learn and utilize effectively. If you go into weight lifting without a solid knowledge base or the right trainer support, you will likely perform the movements with bad form. Bad form leads to injury, so you need to spend the time learning the movements, including good Form and how to properly apply Power to the weight.

Weight Machine Pro’s and Con’s

Good Stuff:

Easy Weight Change

Most weight machines are incredibly simple to adjust between sets and athletes. Generally it’s as easy as moving a pin up or down a stack of weights housed inside the machine body. This means you spend less time changing resistance and more time working.

Reduced Risk, Good for Beginners

Most of the risk of free weights comes from increased range of motion and the freedom of movement you have when moving, which as we stated above is mitigated by learning good Form. Weight machines remove the risk of going outside the Form of the exercise by forcing you to follow a set path of movement. This is good for beginners, as it allows them to start developing their range of motion in a safer manner, especially if little to no assistance is available from a trainer.

Easier to Learn

As we mentioned just now, machines are much easier to learn than free weights. Often a machine will have text and pictorial directions on how to use them, so a person new to exercise can see some benefit even on their first try.

Easy to Isolate Muscles

Because machines allow you to work muscle groups without engaging peripheral muscles (stabilizers, for example), you are able to isolate and work on muscle groups more specifically. This can be good if you have a trouble group you want to work on, either due to lack of conditioning or injury. For instance if you suffered a bad muscle tear and need to work on biceps separately from anything else, you could do seated machine curls.

Bad Stuff

More Controlled Range of Motion

The controlled range of motion has it’s perks (see above) but it also has disadvantages. When you artificially inhibit or control the range of motion for any exercise, you are essentially telling the body “this is how we should move”. This prevents your body from learning the full range, and fails to activate peripheral muscles on a regular basis. If and when you try to transition to free weights, you’ll notice a lot of “wobbliness” in movements you’ve been doing too much on only machines. When trying to do the same exercises off the machine, you will likely also see that those parts of the free movement that fall just outside the machine range will be much, much weaker than the rest of the exercise.

Reduced Peripheral Benefits

Following on the last point, when you cut the stabilization muscles out of a workout, you lose a lot of the benefit you normally get from doing a given exercise. Sure, the seated lat pull may work your lats and biceps, but you lose all the benefit to your core that you get from just doing pull-ups. This, again, leads to being shaky on non-machine exercises or at extreme cases can make you unable to complete the same movements off the machine.

False Sense of Strength

Machines target big muscle groups and tend to ignore peripherals, which means you’re not actually building the strength you think you are. Being able to move a lot of weight in a very controlled pattern doesn’t necessarily prepare you to move the same, or even similar, weight when you are moving free form. An example might be building leg strength in a leg press/squat machine. In the machine you can move 400 lbs through a controlled range where Form is taken care of by the machine itself. You can focus entirely on putting out power. BUT if you try a similar movement, lets say the back squat, with free weights, your total weight is likely to plummet to 56-60% of your max in the machine. This is because actually lifting something on your back is about more than just how strong your legs are: you also need your back, abs, etc. to control the weight and keep good Form.

So, which is better: Free Weights or Weight Machines?

Yes. No. Both. Neither.

You should be using both methods of training according to your level of skill and your goals.

Beginners who do not have a trainer or skilled workout partner should start with basic weight machines, in order to start building the proprioception to perform good movements. However, you’re not a beginner forever! Once you become comfortable moving weight, it’s time to start leaning both body weight and free weight movements. Again, start simple and seek advice from trainers and coaches. Start working both free weights and weight machines into your routine until free weights mostly dominate your exercises.

Experienced lifters should be doing mostly free weights, as they have the most overall benefits to your physique. However it warrants mentioning that weight machines can be good for problem areas and working a single muscle group a little extra. If you want to isolate a movement using a machine, do so at the end of your workout after you’ve already worked through free weights. This way you get the maximum benefit from both training types.

Injured athletes can use machines to help isolate and rehabilitate the injured areas whenever they are otherwise unable to complete a free weight movement that works that area. You can build in rehab sets with other free weight movements that don’t tax your injury site, and slowly get back strength and function over time, so you can get back into free weight movements with all areas.

Well, that’s it! Tune in next time for more fitness-y goodness!