Pilates and ActivCore target both types of skeletal muscles, Type I fibers and Type II fibers. The percentage of Type I fibers and Type II fibers in muscles is genetically determined.
Type
I muscle fibers, also called "slow twitch fibers," contract at a slow
rate and do not fatigue easily. They are muscles of endurance, and the
deep postural muscles of the body (the multifidus, transversus
abdominus, etc.) are examples of muscles comprised of type I fibers.
Marathon runners typically have a higher percentage of slow twitch
fibers in their legs, as they are more inclined to run long distances.
Type
II muscle fibers are also called "fast twitch fibers" because of their
fast rate of contraction. Type II fibers are responsible for power and
speed. Sprinters and hurdlers have a higher concentration of fast
twitch fibers in their legs, hence the greater muscle bulk and the
explosive power they produce.
As stated, the percentage of slow
twitch fibers (type I) and fast twitch fibers (type II) in the body is
genetically determined. Any training strengthens
either type of fiber -- whether increasing the power as in type II or
increasing the endurance of a muscle as in type I. But increasing the
percentage of fibers in your body is impossible!
Pilates
and ActivCore are excellent training choices because they target both
types of muscles. Pilates encourages engaging the deep spinal
stabilizers and the peripheral musculature in every exercise.
ActivCore engages the core even more than traditional Pilates exercises do because of the instability the Redcord system provides.
To balance muscles in the body, pay attention to your training
regime: if you think any body part of yours is too bulky, then try
using less resistance and increasing repetitions. This will encourage
the slow twitch fibers you have to build their endurance.
If you train (and train and train and train) and feel it takes forever to build a muscle,
then quite possibly, that particular muscle has a higher percentage of
slow twitch fibers naturally. Within reason, the best training may be
increased weight and fewer repetitions. When in doubt, please check in
with a fitness professional, as it is important to increase weight
gradually!
To increase instability in Pilates, exercises with the
stability ball are excellent choices. Try the "Get on the Ball" series
of exercise on www.ultimatepilatesworkouts.com.
To try ActivCore here in New York City, come to Pilates on Fifth! To search for ActivCore in your area, log onto ActivCore.com!