Ed Czajka works out on weight machines because they're available in his apartment gym. But he believes he's gotten better results with barbells and other free weights.
"When you get on the machines, it's brainless pushing or pulling," says Czajka, 43, of Los Angeles. "I've always thought you get a better and more complete workout with free weights."
Is he right? The best way to strength train is one of most enduring controversies in fitness, and recent studies have only added to the confusion.
One published study found that men could lift more weight while doing a traditional bench press with free weights than doing a standing chest press on a cable-based freeform weight machine, suggesting that the free weights more effectively targeted the chest muscles. Meanwhile, another study found that bench presses performed using a BOSU balance trainer or stability ball (for instance, with an experienced lifter lying back on the ball with his feet on the floor — don't try this without a trainer) engaged more muscles, namely those of the core, than the traditional bench press performed from a bench. And a third study concluded that exercisers get stronger using a freeform cable machine, in this case a FreeMotion machine, than a fixed machine.
If trying to make sense of the research makes you want to throw in the towel, take heart in knowing that all of these approaches can help build strength simply because they challenge the muscles, says strength-training expert and author Wayne Westcott, the fitness research director at the South Shore YMCA in Quincy, Mass.
Overall, most good research shows that when it comes to strengthening a particular area, such as the pectoral muscles of the chest, people can get similar results training with free weights and fixed machines, such as Nautilus and Cybex, says Westcott. "Both work very well."
Free weights require a person to stabilize the body to perform the moves so they have the added advantage of working other muscles (nearby muscles, for instance, plus the core muscles of the abs and back), making them more applicable to lifting or performing other strength tasks in real life, experts generally agree.
Similarly, "functional training" approaches, such as those incorporating stability balls, wobble boards or freeform weight machines, tend to do a better job of working the core, but they don't appear to target specific muscles as well, Westcott says.
Gear the routine to your goal
Ultimately, there may not be a single best answer for everyone.
"The type of equipment you utilize really depends on what the overall training goal is," says Jay Dawes, education director at the National Strength and Conditioning Association in Colorado Springs, Colo., and a former personal trainer and strength coach.
Athletes, for instance, may use a combination of strength-training approaches with an emphasis on free weights and freeform machine training that allows for more core stabilization than fixed machines and better replicates real-world moves, Dawes says. Strength exercises — whether with free weights or machines — that are done from a standing, rather than a sitting, position are better in this regard, he says.
Don't miss these Health stories
More women opting for preventive mastectomy - but should they be?
Rates of women who are opting for preventive mastectomies, such as Angeline Jolie, have increased by an estimated 50 percent in recent years, experts say. But many doctors are puzzled because the operation doesn't carry a 100 percent guarantee, it's major surgery -- and women have other options, from a once-a-day pill to careful monitoring.
- Larry Page's damaged vocal cords: Treatment comes with trade-offs
- Report questioning salt guidelines riles heart experts
- CDC: 2012 was deadliest year for West Nile in US
- What stresses moms most? Themselves, survey says
- More women opting for preventive mastectomy - but should they be?
Bodybuilders wanting to bulk up a particular muscle generally do well to work that muscle with a combination of targeted exercises using free weights, machines or both, he says.
Average exercisers who are weight training for overall health and toning may benefit from a combination of techniques that challenge the body in different ways and "reduce the likelihood of staleness and boredom," says Dawes.
That said, if you prefer the variety of free weights or love the simplicity of doing a quick strength circuit on the machines, you'll still benefit from sticking with one or the other, says Leonard Kaminsky, an exercise physiologist at the Ball State University Human Performance Laboratory in Muncie, Ind.
"I'm not as concerned with the type of training — machines, free weights or resistance bands," says Kaminsky. "The No. 1 priority is that they do something resistance-wise" aiming to target all major muscle groups.
Master the moves
For beginners, though, Westcott recommends starting with fixed machines. "In my opinion, there should be a progression for the average person," he says.
Fixed machines are simple to learn and offer stability and support that lessen the risk of injury, says Westcott. Because the machines require your body to move in a certain way, technique is less important. And there's no risk of barbells falling on your head or toes because you've attempted too heavy a lift or your hands got sweaty.
Once you've mastered machines, he says, you can progress to free weights, and possibly incorporate both free weights and machines into your training mix. After that, it's OK to move on to functional training, which requires more base strength in order to perform the moves correctly and safely.
Keep in mind that you'll perform the best on whatever equipment you train with the most, says Westcott. For 20 years, he primarily used Nautilus machines. When he switched to free weights a few years ago, he couldn't pump nearly as much iron as he could on the machines. Now, he can't do as well on Nautilus as he does with free weights and is incorporating both into his routine.
Since Czajka doesn't have access to a lot of free weights, he's started doing calisthenics such as push-ups and pull-ups to supplement the machine workouts he does at his apartment gym. He'll have to join a commercial gym, he says, if he wants access to more free weights. But for now, the apartment gym does have some key fitness benefits — it's convenient and free.
© 2013 msnbc.com