There are many factors that influence balance. We separate them into two main categories: intrinsic, or internal, and extrinsic, or external, factors.
Intrinsic
- Vision: Changes in vision (acuity, contrast, depth perception, and three-dimensional vision) impact balance. This makes it difficult for people to spot environmental hazards and gather important information for kinesthetic awareness.
- Vestibular sensations: The vestibular system is a system of the proprioceptive sense organs located in the inner ear that signal information about posture, movement, and sense of balance.
- Peripheral sensations (including limb proprioception): Decreased sensation at the ankle and knee are common during aging, and they can be an indicator of fall risk.
- Muscular strength and power: Strength is defined as the maximal force a muscle can exert against a form of resistance in a single effort. Power is force multiplied by velocity. Lower body strength and power decline with age. Reductions in these are predictive of falls.
- Reaction time: Reaction is the time between stimulus and a response. The reaction time of a 60 year old is on an average 25% slower than that of a 20 year old (Signorile, 2011)
- Balance and mobility: Impaired stability when standing, leaning, reaching, and impaired gait mobility are some of the balance and mobility issues that are directly related to falling probability.
- Cognition: Cognition decreases in memory, reasoning, information processing, speed processing, etc. increase the probability of falls.
Extrinsic
- Inappropriate footwear: To decrease fall risk footwear should fit, provide, support, and adhere to the foot.
- Environmental factors: Items like loose rugs, poor lighting, and uneven pavement create environmental hazards. An assessment of the home and community can help prevent falls.
- Medicine management: Polypharmacy is the use of four or more medications by an adult. Any adult in this category is considered high risk for a fall.