Walking-Induced Fatigue Leads to Increased Falls Risk in Older Adults

Abstract

Background For older adults, falls are a serious health problem with over 30% of people over 65 suffering a fall at least once a year. One element often overlooked in the assessment of falls is whether a person’s balance, walking ability and overall falls risk is affected by performing activities of daily living such as walking. Objective This study assessed the immediate impact of incline walking at a moderate pace on falls risk, leg strength, reaction time, gait and balance in 75 healthy adults from 30 to 79 years of age. Subjects were subdivided into five equal groups based upon their age (Group 1, 30–39 years; Group 2, 40–49 years; Group 3, 50–59 years; Group 4, 60–69 years; Group 5, 70–79 years). Methods Each person’s falls risk (using the Physiological Profile Assessment), simple reaction time, leg strength, walking ability and standing balance were assessed prior to and following a period of incline walking on an automated treadmill. The walking task consisted of three 5-minute trials at a faster than preferred pace. Fatigue during walking was elicited by increasing the treadmill incline in increments of 20 (from level) every minute to a maximum of 80. Results As predicted, significant age-related differences were observed prior to the walking activity. In general, increasing age was associated with declines in gait speed, lower limb strength, slower reaction times and increases in overall falls risk. Following the treadmill task, older adults exhibited increased sway (path length 60–69 yrs; 10.2±0.7 to 12.1±0.7 cm: 70–79 yrs; 12.8±1.1 to 15.1±0.8 cm), slower reaction times (70–79 yrs; 256±6 to 287±8 ms), and declines in lower limb strength (60–69 yrs; 36±2 to 31±1 kg: 70–79 yrs; 32.3±2 to 27±1 kg). However, a significant increase in overall falls risk (pre; 0.51±0.17: post; 1.01±0.18) was only seen in the oldest group (70–79 years). For all other persons (30–69 years), changes resulting from the treadmill-walking task did not lead to a significant increase in falls risk. Conclusions As most falls occur when an individual is moving and/or fatigued, assessing functional properties related to balance, gait, strength and falls risk in older adults both at rest and following activity may provide additional insight.

Intraindividual Variability of Neuromotor Function Predicts Falls Risk in Older Adults and those with Type 2 Diabetes

“…The aim of the current study was to examine the patterns of inter-and intraindividual variability of falls risk, leg strength, reaction time and walking ability for both healthy older adults and older persons with T2DM. As expected, the results revealed that increasing age for both groups was reflected by a systematic increase in falls risk and a decline (i.e., slowing) of general motor function in reaction time and walking speed (Dykiert, Der, Starr, & Deary, 2012b;Himann, Cunningham, Rechnitzer, & Paterson, 1988;Morrison et al, 2016;Welford, 1988). Importantly, in addition to this neuromotor slowing, there was increased intraindividual variability for these same measures as a function of increasing age, with the older T2DM individuals being more variable compared to healthy controls.…”

Quedas recorrentes e fatores de risco em idosos institucionalizados

“…Older persons are more susceptible to muscle fatigue due to decreased muscle strength and sarcopenia. It has been shown that 28 fatigue leads to greater postural oscillation, decreased obstacle negotiation ability, and an increased risk of falling among older persons. Furthermore, some authors have suggested that fatigue should no longer be considered a physical event but rather a sensation or emotion resulting from the interaction between the above aspects and cognitive factors 29,30 explained by the central governor model 31 , in which the regulation of the activity of motor neurons that innervate skeletal muscle fibers to maintain homeostasis by central nervous system is predominantly emotional.…”

Falls in older adults with multiple myeloma

“…In one mechanistic study, participants walked on an inclined treadmill, and after fatiguing, older participants exhibited increased sway, slower reaction time, decreased lower leg strength, and increased fall risk. 26 Participants who reported that, overall, their health was fair or poor were 86% more likely to fall (aOR 1. survey item is nonspecific, asking "In general, would you say your health is: excellent/very good/good/fair/poor?" Respondents may have been taking into account comorbidities or functional status, both of which have been associated with falls in prior studies.…”