Body Balance: Systems, Factors, and Training for Stability

Body balance (postural stability) is the ability to maintain the center of mass over the base of support during static/dynamic activities.

Integrated Sensorimotor Systems

• Visual: Spatial orientation, obstacle detection.
• Vestibular (inner ear): Head position/motion (semicircular canals, otoliths).
• Proprioceptive (somatosensory): Joint position, muscle length, pressure (mechanoreceptors).

CNS (cerebellum, brainstem, cortex) integrates inputs → motor commands for postural adjustments.

Key Factors Affecting Balance

• Age-related decline (sensory, motor, cognitive).
• Neurological: stroke, Parkinson's, MS, neuropathy, cerebellar ataxia.
• Vestibular: BPPV, neuritis, Ménière's.
• Musculoskeletal: weakness, arthritis, amputation, foot deformity.
• Medications: sedatives, antihypertensives, anticholinergics, opioids.
• Vision impairment, alcohol, fatigue.

Assessment

• Clinical: Romberg, tandem stance, single-leg stance, Functional Reach, Timed Up-and-Go (TUG), Berg Balance Scale.
• Instrumented: Force plates, wearable sensors.

Training & Fall Prevention

• Exercise: Tai chi, yoga, perturbation training, strength (lower extremity/core), gait/agility drills.
• Multifactorial: Home hazard reduction, medication review, vision correction, footwear, vitamin D.
• Assistive devices: Cane, walker, orthotics.

Balance training reduces fall risk by 20-40% in older adults.