- The ability to maintain the body center of gravity over its
base of support (NSCA 2012).
- The ability to return to a desired position or trajectory
following a disturbance. (NSCA 2012).
- Equilibrium is the state of no acceleration (no change of
speed or direction) of body.
- Static Equilibrium refers to the body at rest or motionless.
- Dynamic Equilibrium refers to the body in motion with unchanged
acceleration created by balanced applied and inertial force
- Center of Gravity:
- The point at which all body mass is equally balanced or equally
distributed in all directions.
Proprioceptive ability does not appear to be related to performance
(NSCA 2012). Bompa (2015) suggests that the importance of balance
training in sports and fitness is more of an unfounded speculation
than a certainty.
...balance is not and never has been considered a limiting
factor for performance.
Despite the reality of biomechanics, some people still believe
that balance training needs to be trained as a separate element
in training like strength or flexibility. In actuality, balance
is simply trained as a by-product of other training abilities
such as strength, power, agility, and flexibility. (Bompa 2015)
Athletes need a minimum amount of balance and stability. Rather
than attempting to maximize balance and stability traits in all
those of average abilities, fitness professional should direct
their efforts toward those who are considered poor performers
and assign remedial work based on their deficiencies. (NSCA 2012)
The equipment promoted as improving balance has little, if
any, effect on an athlete's performance. Children in the initiation
stage of development, such as kindergarten, might really enjoy
some of these balance exercises. Maintaining balance on a balance
board certainly involves some degree of difficulty. However,
to claim that these exercise can positively affect sport training
or that repeating some of these exercises will improve athletic
performance is an insult to any good student of sport science.
Specificity of Balance, Proprioception,
and Core Stability
any sport, the optimal method to improve balance, proprioception,
and core stability is to practice the skill itself on the same
surface on which the skill will be performed during competition.
There is little transfer between balancing skills because balance
is skill specific. For example, having a gymnasts practice on
a wobble board balance will not be improved balance on the beam.
Similarly, having a baseball pitcher stand on a foam roller while
throwing a medicine ball may not improve proprioception when
throwing from a mound. Likewise, having a football player stand
on a stability disks while performing squats may not improve
core stability when running through a defensive line. Performing
resistance exercises on stability balls, foam rollers, wobble
boards, and variations of such equipment has not been shown to
enhance sports related skills. (Willardson 2004)
Decreased Performance on Balance Equipment
Subjects strengthened on stable surfaces performed significantly
better in athletic measures than subject doing the same exercises
on inflated rubber disks (Cressey 2007). Cressey, et al (2007)
Using inflatable rubber disks attenuates performance
improvements in athletes.
Unstable devices account for 44% less muscle activity and
70% less muscle force output than stable surfaces. (Behm 2002)
Efficacy of BOSU Balance Trainer for
Core Muscle Activation
The activity of core muscles (rectus abdominis, external oblique
abdominis, transversus abdominis/internal oblique abdominis,
and erector spinae) were compared when standing on a BOSU balance
trainer versus a stable floor while performing various exercises
(back squat, deadlift, overhead press, and arm curl). No significant
differences of core activation were observed between the BOSU
and stable floor when performing exercises with the same workload
50% of 1-RM. The researches concluded that this study did not
demonstrate any advantage in using the BOSU Balance Trainer and
these lifts can be performed while standing on a stable floor
without losing any training benefits of core muscle activation.
Balance Training During Rehabilitation
Balance performance and robustness are impaired following
injury. This is likely due to compromised strength, decreased
proprioception, and altered programming. Although balance training,
in itself, does not appear to decrease risk of re-injury, risk
of re-injury may be reduced when balance training is one component
of an intervention program. Proprioceptive deficits caused by
an injury can be improved during the rehabilitation process,
but there's no evidence to support the ability to improve proprioception
and healthy, asymptomatic people. (NSCA 2012)
Reducing ACL Injury Risk in Female Athletes
Myer (2006) suggests both plyometric and dynamic stabilization/balance
exercises should be included in injury-prevention protocols.
Plyometric training affects sagittal plane kinematics primarily
during a drop vertical jump, whereas balance training affects
sagittal plane kinematics during single-legged drop landing.
Weight Training Decreases Fear of Falling in Elderly
Elderly (ages 67 to 97 years of age) who participated in a
free weight program reported a decreased fear of falling. They
also increased functional performance, increased perception of
health, and decreased need for medication. (Brill 1998)
Factors Increasing Stability
- Center of gravity falls within base of support
- decrease in stability when center of gravity becomes near
edge of base
- Larger base
- Greater weight
- Lower center of gravity
- When anticipating an oncoming force
- place center of gravity near the side of base of support
expected to receive force
- extending base of support in direction of expected force
- Greater friction between body and surfaces it contacts
- Rotation about axis
- moving cycle is easier to balance that stationary cycle
- Kinesthetic physiological functions
- vestibular system, vision, touch, and kinesthetic awareness
- Walking throws body in and out of balance with each step
- placing the center of gravity beyond base of support
- A large component of sprint acceleration is created by falling
- placing the center of gravity beyond base of support
- Jumping attempts to raise body's center of gravity upward
- Also see calculating Center
Balance Exercise Examples
- Balance Board
- Medicine Ball
Behm DG, Anderson K, Curnew RS (2002). Muscle force and
activation under stable and unstable conditions. J Str Cond Res.
Bompa T, Carrera M (2015). Conditioning for Young Athletes.
Brill PA, Matthews M, Mason J, Davis D, Mustafa T, Macera
C (1998). Improving functional performance through a group-based
free weight strength training program in residents of two assisted
living communities. Physical and Occupational Therapy in Geriatrics,
Cressey, E.M., et al. (2007). The effects of ten weeks
of lower-body unstable surface training on markers of athletic
performance. J Str Cond Res. 21(2): 561-567.
Myer GD, Ford KR, McLean SG, Hewett TE. (2006) The effects
of plyometric versus dynamic stabilization and balance training
on lower extremity biomechanics. The American Journal of Sports
Medicine, 34(3): 445-455.
NSCA (2012) NSCA's guide to tests and assessments.
Willardson JM, Fontana FE, Bressel E (2009). Effect of
surface stability on core muscle activity for dynamic resistance
exercises. Int J Sports Physiol Perform. 4(1), 97-109.
Willardson JM (2004). The effectiveness of resistance exercises
performed on unstable equipment. Strength and Conditioning Journal;
26 (5), 70-74.