Benefits of Higher Cardiovascular and Motor Coordinative Fitness on Driving Behavior Are Mediated by Cognitive Functioning: A Path Analysis

Abstract

Driving is an important skill for older adults to maintain an independent lifestyle, and to preserve the quality of life. However, the ability to drive safely in older adults can be compromised by age-related cognitive decline. Performing an additional task during driving (e.g., adjusting the radio) increases cognitive demands and thus might additionally impair driving performance. Cognitive functioning has been shown to be positively related to physical activity/fitness such as cardiovascular and motor coordinative fitness. As such, a higher fitness level might be associated with higher cognitive resources and may therefore benefit driving performance under dual-task conditions. For the first time, the present study investigated whether this association of physical fitness and cognitive functioning causes an indirect relationship between physical fitness and dual-task driving performance through cognitive functions. Data from 120 healthy older adults (age: 69.56 ± 3.62, 53 female) were analyzed. Participants completed tests on cardiovascular fitness (cardiorespiratory capacity), motor coordinative fitness (composite score: static balance, psychomotor speed, bimanual dexterity), and cognitive functions (updating, inhibition, shifting, cognitive processing speed). Further, they performed a virtual car driving scenario where they additionally engaged in cognitively demanding tasks that were modeled after typical real-life activities during driving (typing or reasoning). Structural equation modeling (path analysis) was used to investigate whether cardiovascular and motor coordinative fitness were indirectly associated with lane keeping (i.e., variability in lateral position) and speed control (i.e., average velocity) while dual-task driving via cognitive functions. Both cardiovascular and motor coordinative fitness demonstrated the hypothesized indirect effects on dual-task driving. Motor coordinative fitness showed a significant indirect effect on lane keeping, while cardiovascular fitness demonstrated a trend-level indirect effect on speed control. Moreover, both fitness domains were positively related to different cognitive functions (processing speed and/or updating), and cognitive functions (updating or inhibition), in turn, were related to dual-task driving. These findings indicate that cognitive benefits associated with higher fitness may facilitate driving performance. Given that driving with lower cognitive capacity can result in serious consequences, this study emphasizes the importance for older adults to engage in a physically active lifestyle as it might serve as a preventive measure for driving safety.

The association of executive functions and physical fitness with cognitive-motor multitasking in a street crossing scenario

“…Differential effects of different components of cognitive functioning and physical tness on other task parameters were also found for multitasking driving [11]. The results of both studies suggest that an overall task performance (across all task parameters) does not depend on a single component of cognitive functioning or physical tness but rather on combining several components.…”

“…Therefore, it might be assumed that the effects of executive functions, motor coordinative and cardiovascular tness on cognitive-motor multitasking are interrelated. For multitask driving, it could be demonstrated that there are direct and indirect effects of motor coordinative and cardiovascular tness on multitasking performance [11]. Both physical tness components were related to executive functions, directly affecting multitasking driving.…”

“…Physical tness is a multidimensional concept that includes cardiovascular and motor coordinative tness. Both types of tness might bene t cognitive-motor multitasking but through different (neuro-) biological mechanisms [11,21,22]. Cardiovascular tness refers to the physical work capacity of an individual, in the form of oxygen capacity per kilogram of body weight over time [23,24].…”

“…Since the mentioned work on multitask walking only investigated the effects of isolated cognitive functioning and physical tness components on cognitive or motor multitasking performance, one cannot conclude whether the results of executive functions and cardiovascular and motor coordinative tness differ for cognitive-motor multitasking performance. However, since walking varies from driving in terms of motor and cognitive requirements, results from [11] might not be transferable to multitask walking.…”

“…In turn, for other individuals, it is the opposite. These individual differences in cognitive-motor performance are thought to be related to different levels of cognitive functioning and physical tness, which are in uenced by lifestyle factors such as physical activity or intellectual engagement [9,11]. As we will detail in the subsequent paragraphs, until now, available work focused on isolated associations between cognitive functioning or physical tness on the one hand and cognitive or motor multitasking performance on the other hand.…”