Influence of energy cost and physical fitness on the preferred walking speed and gait variability in elderly women

Abstract

Typically gait speed decreases and gait variability increases in elderly. The aim of this study was to define the influence of energy cost of walking on gait speed and of health-related physical fitness on gait variability. Thirty healthy young and older women were recruited in the study. Energy cost of walking (Net) was analyzed with indirect calorimetry while a kinematic analysis was performed with an optoelectronic system to calculate gait variability (GV) during treadmill walking at different speeds. Gait speed was defined as the preferred walking speed (PWS) of the subject and health related physical fitness (HRPF) comprised body fat, strength, flexibility, and cardiorespiratory fitness. In healthy elderly women, the coefficient of variation of step width was found to be a better indicator of GV than stride time, stride length and double support coefficients of variation. GV was not affected by age allowing a high PWS. Furthermore, significant associations, adjusted for age, body mass index and number of falls, were identified neither between Net and the PWS, nor between HRPF and GV; only a significant association was found between hand-grip strength and gait stability. Findings highlighted the importance to evaluate hand-grip strength as an indicator of gait efficiency.

Domain-Specific and Total Sedentary Behavior Associated with Gait Velocity in Older Adults: The Mediating Role of Physical Fitness

“…Our findings that a higher level of physical fitness is associated with faster gait velocity are in line with previous evidence [13,[16][17][18]. In cross-sectional studies, walking speed has been associated with knee extensor strength over the entire range of strength [16].…”

“…Previous evidence has shown that faster gait velocity [13], less time spent in sedentary behaviors [30], and higher level of physical fitness [30] are crucial factors for maintaining successful and healthy aging and higher quality of life [13]. As mentioned in the Introduction section, only 25% of older adults meet the minimum recommended activity levels of at least 150 min of moderate-intensity aerobic physical activity throughout the week or do at least 75 min of vigorous-intensity aerobic physical activity throughout the week, or an equivalent combination of both [19].…”

“…Additionally, gait time decreases linearly with increasing knee extensor strength [17] and strength measure (composed of sum of knee extension, knee flexion, and ankle dorsiflexion muscle strength scores) is the strongest predictor of six-meter walking speed [18]. Moreover, one previous study has shown that hand grip strength was significantly associated with gait stability [13]. Recently, two longitudinal studies examined the association between gait velocity and physical performance [27,28].…”

“…The key of successful aging represents functional independence and maintaining high quality of life [13], often accompanied by a high level of physical fitness. In older adults, the level of physical fitness is significantly reduced due to higher rates of disabilities and limitations [2].…”

“…In older adults, the level of physical fitness is significantly reduced due to higher rates of disabilities and limitations [2]. Although a higher level of physical fitness reduces the time spent in sedentary behavior [14,15] and increases gait velocity [13,[16][17][18], according to available literature no study has investigated the potential mediating role of physical fitness in the association between domain-specific and total sedentary behavior and gait velocity. Since only 25% of older adults meet the recommended levels of physical activity proposed by the World Health Organization [19], it is necessary to identify individuals in need of increasing their physical fitness level in order to decrease sedentary lifestyle and improve gait parameters.…”