Have you ever wondered if there really is a difference between fixed
and freeform resistance equipment when it comes to improving strength? Data
collected for the January issue of the National Strength and Conditioning Asso┬¡ciation’s
Journal of Strength and
Conditioning Research
(2008; 22 [1], 75-81) compared the two types
of equipment to determine which is better for strength gains.

Following initial assessments,
30 sedentary male and female subjects were randomly divided among a nonexercise
control group (C), a freeform group (FF) and a fixed-form (FX) group. The FX
group used a plate-loaded, fixed-motion machine, while the FF group used a
machine that “was cable-based and allowed motion in multiple ranges within the
exercised joint’s capability.” Subjects performed 8-12 repetitions of a variety
of strength training exercises 2 times per week for 16 weeks.

The FF group showed twice as
much strength improvement as the FX group (115% vs. 57%, respectively). Study
authors also found a 111% increase in joint pain among the FX group, whereas
joint pain decreased by 30% in the FF group, with no new symptoms occurring
upon study completion. Balance improved in both groups; however, the FF group
had a 245% increase in balance capabilities compared with a less significant
49% increase among the FX group.

“This study finds that the assumption in fixed
training (i.e., it is better to isolate a muscle in order to strengthen it) may
be inaccurate,” stated the researcher. While fixed-motion machines might be
necessary for specific populations, the author suggested, capable exercisers
seeking significant improvements in strength and balance should take advantage
of freeform equipment. Conceding that more research was required in this area,
he nonetheless concluded that “without question this training format had advantages
for beginner exercisers.”