Effects of Physical-Cognitive Dual Task Training on Executive Function and Gait Performance in Older Adults: A Randomized Controlled Trial

Abstract

Physical and cognitive training seem to counteract age-related decline in physical and mental function. Recently, the possibility of integrating cognitive demands into physical training has attracted attention. The purpose of this study was to evaluate the effects of twelve weeks of designed physical-cognitive training on executive cognitive function and gait performance in older adults. Thirty-six healthy, active individuals aged 72.30 ± 5.84 years were assigned to two types of physical training with major focus on physical single task (ST) training (n = 16) and physical-cognitive dual task (DT) training (n = 20), respectively. They were tested before and after the intervention for executive function (inhibition, working memory) through Random Number Generation and for gait (walking with/without negotiating hurdles) under both single and dual task (ST, DT) conditions. Gait performance improved in both groups, while inhibitory performance decreased after exercise training with ST focus but tended to increase after training with physical-cognitive DT focus. Changes in inhibition performance were correlated with changes in DT walking performance with group differences as a function of motor task complexity (with/without hurdling). The study supports the effectiveness of group exercise classes for older individuals to improve gait performance, with physical-cognitive DT training selectively counteracting the age-related decline in a core executive function essential for daily living.

Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Figure 1

CONSORT flowchart of participants.

Figure 2

Method schematic. Cognitive assessment (RNG) conditions: (1) ST = single task (i.e., RNG only), (2) sDT = simple gait-cognitive dual task (i.e., flat walking + RNG), and (3) cDT = complex dual task (i.e., walking while negotiating hurdles + RNG). Gait assessment conditions: (1) sST = simple single task (i.e., flat walking), (2) cST = complex single task (i.e., walking while negotiating hurdles), and (3) sDT = simple dual task (i.e., flat walking + RNG) and cDT = complex dual task (i.e., walking while negotiating hurdles + RNG). EXP = experimental group; CON = control group.

Figure 3

Training effects on inhibitory performance. Significant decrement (∗∗∗ = p < .001) was seen in the control group (CON), while a marginally significant increment (# = p < .041) was seen in the experimental group (EXP).

Figure 4

Coefficients of variations of gait speed (a) and stride time (b) following the intervention in simple (flat) and complex (hurdling) walking task conditions. ∗∗∗ = p < 0.001.

Figure 5

Correlations between pre-post changes in inhibition (horizontal axis) and coefficients of variations of stride length (vertical axis) in simple (panel (a)) and complex (panel (b)) gait-cognitive task conditions. Regression lines represent significant correlations found for the control group (CON) in the simple condition, but for the experimental group (EXP) in the complex condition.