Motor-cognitive exercise with variability of practice and feedback improves functional ability and cognition in older individuals.

BACKGROUND: Motor-cognitive dual-task training seems the most favorable form of exercise for functional and cognitive improvements in older individuals.  The optimal exercise regime is still uncertain, and the potential benefits of qualitative parameters of exercise prescription such as feedback provision and practice variability are mostly unknown. AIMS: To verify the effects of a motor-cognitive dual-task training with feedback provision and variability of practice for improving functional ability and cognition in older individuals. METHODS: Thirty individuals (3 men) aged over 65 years were tested on walking speed, static and dynamic balance, lower limb strength, and cognition before and after a 5-week motor-cognitive intervention. Training consisted of twice weekly, 30 min gross-motor coordination exercises with variable practice conditions combined with stimulus-response cognitive tasks generated by an interactive device. Participants were divided into an experimental group and a control group, respectively receiving and nonreceiving feedback during training. A 2 × 2 ANOVA was used to verify the effects of training. RESULTS: Both groups improved static and dynamic balance (p < 0.05), walking speeds (p < 0.05), lower limb strength (p < 0.05) and cognitive functions with greater gains observed in the experimental group (p < 0.01). DISCUSSION: Variability of practice applied to motor-cognitive dual-task training is effective for improving, in only 5 weeks, functional ability and cognitive processing in older individuals. These changes were possibly afforded through motor and cognitive enhancement induced by exercise complexity. Provision of feedback seems to particularly benefit cognitive functions. CONCLUSIONS: Brief motor-cognitive dual-task training using practice variability and feedback seems effective for counteracting the age-related cognitive and functional decline.

Reliability of walking speed in basic and complex conditions in healthy, older community-dwelling individuals.

BACKGROUND: There is a paucity of reliability data for walking speed tests in complex conditions to assess functioning in healthy older individuals. AIMS: To evaluate the absolute intra- and intertest reliability of walking speed performed in basic and complex conditions in healthy older individuals. METHODS: Fifty-two men and women of mean age 69.7 ± 3.2 years were tested for habitual and maximal walking speed. Maximal speed was also assessed under different conditions, including walking on a path of reduced width; picking up objects; stepping over hurdles; stepping over hurdles wearing sunglasses and finally, carrying a box. Two testing sessions (separated by 4 weeks) of two trials each were administered. Reliability was analysed by intra-class correlation coefficient (ICC), minimal detectable change (MDC) and Bland-Altman plots with limits of agreement (LOA). RESULTS: Intrasession ICCs ranged from good to excellent (0.89-0.95) except for picking up objects (0.44). Intersession ICCs were moderate to good (0.60-0.78) and %MDCs were acceptable (14-24%). Bland-Altman plots suggested a good agreement between the two testing sessions at group level (mean differences from - 0.02 to - 0.11 m/s), and limited agreement between testing sessions at individual level (upper LOA from 0.13 to 0.37 m/s and lower LOA from - 0.29 to - 0.49 m/s). CONCLUSIONS: Complex walking speed tests are generally reliable measures displaying good and moderate intra- and inter-session reliability. Such tests seem a more suitable functional assessment tool for heathy older subjects compared with simple walking. Some learning effect may be present and further reliability studies are needed.

Effects of a Judo Training on Functional Fitness, Anthropometric, and Psychological Variables in Old Novice Practitioners.

This study aimed to investigate the effects of a 4-month judo training (1 hr session, biweekly) on physical and mental health of older adults (69.7 ± 4.2 years). Participants (N = 30) were assigned to a judo novice practitioners group (n = 16) or a control group (n = 14), which did not receive any training. Before and after the program, they underwent anthropometric (body mass index and waist and hip circumferences); functional fitness (upper and lower body flexibility and strength, coordination); and psychological assessments (perceived physical and mental health, body image, and fear of falling). The judo group showed reductions of waist circumference (Δ = -1%, d = 0.2) and improvements for lower and upper body flexibility (Δ = +69%, d = 0.4 and Δ = +126%, d = 0.5, respectively) and strength (Δ = +12%, d = 0.6 and Δ = +31%, d = 1.6, respectively). The control group showed a decline in lower body strength (Δ = -12%, d = 0.8). Psychological variables did not reveal statistically significant effects. Judo seems beneficial for improving anthropometric and functional fitness variables, relevant aspects of successful aging.

Measures of static postural control moderate the association of strength and power with functional dynamic balance.

BACKGROUND AND AIMS: Age-related reductions in strength and power are considered to negatively impact balance control, but the existence of a direct association is still an issue of debate. This is possibly due to the fact that balance assessment is complex, reflects different underlying physiologic mechanisms and involves quantitative measurements of postural sway or timing of performance during balance tasks. The present study evaluated the moderator effect of static postural control on the association of power and strength with dynamic balance tasks. METHODS: Fifty-seven healthy 65-75 year old individuals performed tests of dynamic functional balance (walking speed under different conditions) and of strength, power and static postural control. RESULTS AND CONCLUSIONS: Dynamic balance performance (walking speed) was associated with lower limb strength and power, as well as postural control under conditions requiring postural adjustments (narrow surface walking r(2) = 0.31, p < 0.001). An interaction effect between strength and static postural control was found with narrow surface walking and talking while walking (change of ß 0.980, p < 0.001 in strength for 1 SD improvements in static postural control for narrow walking, and [Formula: see text] -0.730, p < 0.01 in talking while walking). These results indicate that good static postural control facilitates the utilisation of lower limb strength to better perform complex, dynamic functional balance tasks. Practical implications for assessment and training are discussed.

Cognitively challenging physical activity benefits executive function in overweight children.

This study tested the association between aerobic fitness and executive function and the impact of enhanced, cognitively challenging physical activity on executive function in overweight and lean children. Seventy children aged 9-10 years were assigned to either a 6-month enhanced physical education programme including cognitively demanding (open skill) activities or curricular physical education only. Pre- and post-intervention tests assessed aerobic capacity (Leger test) and two components of executive function: inhibition and working memory updating (random number generation task). Indices of inhibition and memory updating were compared in higher- and lower-fit children and intervention effects were evaluated as a function of physical activity programme (enhanced vs. curricular) and weight status (lean vs. overweight). Results showed better inhibition in higher- than lower-fit children, extending the existing evidence of the association between aerobic fitness and executive function to new aspects of children's inhibitory ability. Overweight children had more pronounced pre- to post-intervention improvements in inhibition than lean children only if involved in enhanced physical education. Such intervention effects were not mediated by aerobic fitness gains. Therefore, the cognitive and social interaction challenges inherent in open skill tasks, even though embedded in a low-dose physical activity programme, may represent an effective means to promote cognitive efficiency, especially in overweight children.

A Nonpharmacologic Treatment for Anxiety in Older Adults Based on Cognitive-Motor Training With Response-Generated Feedback.

OBJECTIVES: Simultaneous combinations of cognitive and physical exercises (cognitive-motor dual-task training [CMDT]) are more effective than physical and cognitive training alone in counteracting the decline of older adults and promoting physical and psychological well-being. The CMDT can be particularly effective in improving cognitive and functional abilities. Here, we validated an innovative nonpharmacologic intervention for anxiety and general well-being in older people by combining CMDT and response-generated feedback (RGF) principles. As outcomes, anxiety, cognitive functions, and functional mobility were evaluated. In addition, electroencephalographic methods were employed to investigate the neural basis of the possible intervention effects. METHODS: Thirty older adults were divided into an experimental group trained using a CMDT + RGF protocol and a control group using the CMDT only. The CMDT + RGF consisted of the simultaneous execution of whole-body exercises, cognitive tasks that were realized using interactive devices, and continuous feedback on every response. RESULTS: Results showed decreased anxiety and increased response speed in the experimental group, and both groups improved their functional ability and response accuracy after the intervention. According to electroencephalographic results, both groups showed an increase in the bilateral prefrontal cortex anticipatory activity, but the experimental group also showed a further increase in the left prefrontal cortex and in the premotor areas anticipatory functions. DISCUSSION: This study confirms the effectiveness of the proposed intervention on anxiety by adopting a nonpharmacology treatment that could affect public and individual health costs by proposing an alternative approach to expensive medications and psychotherapy and could significantly improve older adults' quality of life.

Judo for older adults: the coaches' knowledge and needs of education.

This study aimed to explore the views of judo coaches on their perceived knowledge (PK) and needs for education (NE) for training older practitioners. In total, 470 international (Europe = 48%, Americas = 22%, Africa = 23%, Asia = 5% and Oceania = 2%) judo coaches (IJF: level 1 = 55,3%, level 2 = 33%; judo black belt: 3,4 ± 1,7 dan; F = 15%; university education: 68% >BA) responded an online survey encompassing demographic information and 35 items relevant to training older adults (Aging process; Safety and First Aid; Organization & Environment; Physiology and Fitness; Psychology & Mental Health; Teaching & Training) to be rated on a 7-point Likert scale for PK and NE. Non parametric statistics (p > 0.05) was applied to ascertain differences and relationships between PK and NE, respectively. A bivariate go-zone plot was used to highlight items with the lowest PK and the highest NE mean values. The coaches reported high PK (4.5 ± 0.3 pt) and NE (4.7 ± 0.1 pt) values, with significant higher PK values emerging for high education levels and judo experience. In considering their unique needs and special role, the judo coaches presented valuable insights to develop a sustainable educational curriculum tailored to train older judo practitioners.

Executive function moderates the role of muscular fitness in determining functional mobility in older adults.

BACKGROUND AND AIMS: Both physical and cognitive factors are known to independently predict functional mobility in older people. However, the combined predictive value of both physical fitness and cognitive factors on functional mobility has been less investigated. The aim of the present study was to assess if cognitive executive functions moderate the role of physical fitness in determining functional mobility of older individuals. METHODS: Fifty-seven 65- to 75-year-old healthy participants performed tests of functional mobility (habitual and maximal walking speed, maximal walking speed while picking up objects/stepping over obstacles), physical fitness (peak power, knee extensors torque, back/lower limb flexibility, aerobic fitness), and executive function (inhibition and cognitive flexibility). RESULTS: Maximal walking speeds were predicted by physical fitness parameters and their interaction with cognitive factors. Knee extensor torque emerged as the main predictor of all tested locomotor performances at maximal speed. The effect of peak power and back/lower limb flexibility was moderated by executive functions. In particular, inhibition and cognitive flexibility differed in the way in which they moderate the role of fitness. High levels of cognitive flexibility seem necessary to take advantage of leg power for walking at maximal speed. In contrast, high levels of inhibitory capacity seem to compensate for low levels of back/lower limb flexibility when picking up movements are added to a locomotor task. CONCLUSIONS: These findings may have important practical implications for the design and implementation of multi-component training programs aimed at optimizing functional abilities in older adults.

Risks and Benefits of Judo Training for Middle-Aged and Older People: A Systematic Review.

This systematic overview aimed to review studies investigating the benefits and risks of judo training in older people, and to explore practical methodological applications (Registration ID: CRD42021274825). Searches of EBSCOhost, ISI-WoS, and Scopus databases, with no time restriction up to December 2022, resulted in 23 records meeting the inclusion criteria. A quality assessment was performed through the following tools: ROBINS-I for 10 experimental studies, NIH for 7 observational studies, and AGREE-II for 6 methodological studies. A serious risk of bias emerged for 70% of the experimental studies, whereas 100% of the observational and 67% of the methodological studies presented a "fair" quality. When involving 1392 participants (63 ± 12 years; females: 47%), the studies investigated novice (n = 13), amateur/intermediate (n = 4), expert (n = 4), and unknown (n = 3) level judoka by means of device-based, self-reported, and visual evaluation measures. Mean training encompassed 2 ± 1 sessions. week-1 of 61 ± 17 min for 7 ± 6 months. In relation to judo training exposure and outcomes, three main themes emerged: (i) health (56% of studies; e.g., bones, anthropometry, quality of life); (ii) functional fitness (43%; e.g., balance, strength, walking speed); and iii) psychosocial aspects (43%; e.g., fear of falling, cognition, self-efficacy). Although the included studies presented relevant methodological weaknesses, the data support the positive effects of judo training with advancing age. Future research is needed to help coaches plan judo programs for older people.

Educational Needs for Coaching Judo in Older Adults: The EdJCO Focus Groups.

Judo coaches are urged to develop specific competencies and skills for addressing the special needs of older practitioners. Thus, the purpose of this study was to investigate the experts' opinions on judo training in late adulthood to develop sound educational programs for coaches of older judo practitioners. Overall, eighty-eight experts from an international consortium of judo and educational partners participated in national focus groups. During the focus groups, experts discussed five themes and generated statements pertinent to educate coaches to support older judo practitioners (e.g., benefits; necessary knowledge; risks; training groups definition; tools; and tests for monitoring training plans). The initial list of 262 statements was synthesized, validated, analyzed, and organized into a final list of 55 statements and six macro-areas: aging process (n = 10); safety and first aid (n = 6); physiology and fitness (n = 12); psychology and mental health (n = 11); organization and environment (n = 5); adapted judo teaching and training (n = 11). The present international eminence-based study, harmonizing diverse intercultural perspectives, highlighted the specific needs of older judo practitioners. The results of this study will contribute to the structure of a sound educational program for coaches of older judo practitioners to enhance the quality of older adults' sports experiences by linking safety, enjoyment, social interactions, and learning principles.

The Interlink among Age, Functional Fitness, and Perception of Health and Quality of Life: A Mediation Analysis.

In aging societies, physical activity may benefit functional fitness influencing the health of older people. The aim of this study was to explore the interrelation between age and perception of health and quality of life, and the mediating effects of functional fitness in older individuals. One hundred and sixty-six late middle-aged (55-64 years, young-old (65-74 years), and old (75-84 years) adults, divided into senior athletes (n = 44), physically active (n = 59), and sedentary individuals (n = 63) were evaluated for functional fitness (flexibility, strength, interlimb coordination, endurance) and physical (Physical Component Summary-PCS) and mental (Mental Component Summary-MCS) health and quality of life perception. Multiple mediation analyses were applied to assess the relationship between age and PCS and MCS indices and the role of functional fitness-related mediators. For MCS only, the mediation analysis showed a positive total and direct effect of age and a negative total indirect effect through mediators. No effects emerged for PCS. Despite a decline in their functional fitness, older individuals were able to maintain a mental health perception, also demonstrating how beneficial effects of physically active lifestyle on functional fitness can positively impact the cognitive-emotional dimension of mental health with advancing age.

Acute and chronic exercise effects on attentional control in older road cyclists.

BACKGROUND: Research on visual attention control of older road cyclists, who represent a subgroup of traffic participants, is still scarce and studies on their attentional performance while cycling are completely lacking. OBJECTIVE: The present study assessed whether attention control performance of older individuals with a history of participation in road cycling is affected by concomitant cycling exercise. Acute exercise effects were also analyzed in co-aged aerobically trained and sedentary noncyclists to assess whether the acute exercise-cognition relationship is moderated by individual differences induced by chronic sport practice versus sedentary lifestyle. METHODS: Sixteen 60- to 80-year-old cyclists and 32 age-matched noncyclists (16 endurance athletes and 16 sedentary individuals) performed a go/no-go reaction time task in which visual attention was cued by means of spatial cues of different sizes followed by compound stimuli with local and global target features. RESULTS: Older cyclists showed commonalities with and differences from other aerobically trained athletes. Both trained groups, when compared to sedentary individuals, showed shorter reaction time (RT) during physical exercise and a smaller RT disadvantage for unexpected local targets at short stimulus-onset asynchrony (SOA). This expectancy-driven RT effect was stable across SOAs only in the case of cyclists. CONCLUSIONS: Results suggest that chronic long-term aerobic training may lead to favorable conditions for the occurrence of a facilitation effect during acute exercise and for a more efficient use of available resources on attentional tasks involving executive control. These results highlight the importance of considering the effects of aerobic exercise for supporting safe on-road behavior.

Intra- and inter-session reliability of vertical jump performance in healthy middle-aged and older men and women.

Despite its widespread use in performance assessment, the reliability of vertical jump in an ageing population has not been addressed properly. The aim of the present study was to assess intra- and inter-day reliability of countermovement jump in healthy middle-aged (55-65 years) and older (66-75 years) men and women. Eighty-two participants were recruited and asked to perform countermovement jumps on two different occasions interspersed by 4 weeks. The middle-aged groups exhibited excellent absolute reliability for flight height, jump height, peak force, peak power, peak force/body mass, and peak power/body mass, with coefficients of variation ranging from 2.9% to 7.2% in men and from 3.6% to 6.9% in women and moderate-to-high intraclass correlations (0.75 to 0.97 in men; 0.77 to 0.95 in women). The older groups displayed good coefficients of variation (4.2% to 10.8% in men and 3.4% to 9.5% in women), but the intraclass correlations were low-to-high (0.43 to 0.84 in men; 0.42 to 0.93 in women). Overall, intra-session reliability was higher than inter-session reliability. Peak power was by far the most consistent variable, whereas flight and jump height had the most marked variability. The minimum detectable change varied from 10.5% to 33%, depending on the variable examined, suggesting important implications for intervention studies.

The Impact of Exercise Intervention with Rhythmic Auditory Stimulation to Improve Gait and Mobility in Parkinson Disease: An Umbrella Review.

Difficulties in walking, controlling balance, and performing activities of daily living are common problems encountered by individuals affected by Parkinson disease. Scientific evidence suggests that exercise performed with music or auditory or rhythmical cues facilitates movement and improves balance, gait, mobility, and activities of daily living (ADL) performance in patients with PD. The aim of this umbrella review was to summarize available high-quality evidence from systematic reviews and meta-analyses on the effectiveness of rhythmically cued exercise to improve gait, mobility, and ADL performance in individuals with PD. PubMed, Cochrane, and Embase databases were searched from January 2010 to October 2020 for systematic reviews and meta-analyses which had to be (1) written in English, (2) include studies on populations of males and females with PD of any age, (3) analyze outcomes related to gait, mobility, and ADL, and (4) apply exercise interventions with music or auditory or rhythmical cues. Two independent authors screened potentially eligible studies and assessed the methodological quality of the studies using the AMSTAR 2 tool. Four studies, two systematic reviews and meta-analyses, one a systematic review, and one a meta-analysis, were selected. Overall results indicated positive effects for gait and mobility of the use of rhythmic auditory cueing with exercise and suggested that it should be incorporated into a regular rehabilitation program for patients affected by PD. Nonetheless, more primary level research is needed to address the identified gaps regarding the application of this method to physical exercise interventions.

Strength training and gross-motor skill exercise as interventions to improve postural control, dynamic functional balance and strength in older individuals.

BACKGROUND: Loss of balance control is commonly experienced by older individuals. Despite the large amount of research on the effects of exercise on balance the optimal exercise regime is yet to be identified. Most studies have concentrated on strength training due to associations between muscle weakness, balance disfunction and fall risk. The effects of gross-motor skill exercise for balance and postural control have been less investigated. The study aimed to compare the effectiveness of strength training (STT) and gross-motor skill exercise (GMT) on static postural control, dynamic functional balance and strength in healthy older individuals. METHODS: Thirty-eight individuals (65-85 years) participated to GMT or STT for 12 weeks, twice weekly. They were tested pre- and post-training for postural control (Romberg and Tandem positions on a force platform), dynamic functional balance (maximal walking speed in balance-challenging conditions), maximal isometric handgrip strength, maximal knee flexor and extensor strength. RESULTS: Improvements were observed in static postural balance (tandem position, P<0.05, -1.07 mm/s), walking speed (hurdles P<0.01, +0.08 m/s; narrow path P<0.05, +0.07 m/s; picking up P<0.01, +0.07 m/s) knee extensor strength (P<0.001, +10.9 Nm); knee flexor strength improved significantly in the SST group only (P<0.001, +13.9 Nm). There was no correlation between changes in strength and balance. CONCLUSIONS: Static postural balance and dynamic functional balance in healthy elderly may be improved through exercise targeting either muscular strength or coordination, agility and mobility. The present study helps fill the gap in research on gross-motor skill exercise and proposes a suitable exercise alternative to strength for managing static and dynamic balance decline.

Effects of age and limb dominance on upper and lower limb muscle function in healthy males and females aged 40-80 years.

This study investigated the effects of gender, age, and dominance on upper and lower limb muscle function. One hundred and fifty-two males and females aged 20-30 and 40-80 years were recruited. Maximal voluntary isometric strength (MVC) and rate of force development (RFD) of the knee extensor muscles, and handgrip MVC were measured bilaterally as indicators of lower and upper limb muscle function, respectively. In both sexes, significant main effects were found for age (knee extension MVC, RFD, and handgrip MVC) and limb dominance (handgrip MVC). Men exhibited a steeper age-related decline in muscle function than women, particularly in the lower limb [dominant limb: knee extension MVC -56% (men) vs. -35% (women); handgrip MVC -30% (men) vs. -26% (women); RFD -67% (men) vs. -47% (women); non-dominant limb: knee extension MVC -49% (men) vs. -36% (women); handgrip MVC -26% (men) vs. -24% (women); RFD -62% (men) vs. -44% (women)]. Although men showed a higher rate of decline in muscle function, in absolute terms they demonstrated better muscle function than women in all age groups, which has important implications for independence and quality of life. A clear asymmetry in muscle function was evident in both sexes only for handgrip MVC.

Effects of a 4-month judo program on gait performance in older adults.

BACKGROUND: Falls prevention is a critical goal of training program for older individuals. This study explored the effects of a judo program on gait performance in older adults. METHODS: Pre- and post-intervention (15 weeks, 1-hr session, twice a week) step length (cm), gait cycle time (s), speed (m·s-1) and cadence (step·min-1) mean values (AVG) and coefficients of variation (CV) were assessed in a judo (JG: N.=16 novice judoka; age=69.3±3.9 years) and a control (CG: N.=14 healthy older adults; age=70.1±4.5 years) group. Two 3 (motor complexity: flat, corridor, hurdling) ×2 (group: JG, CG) ×2 (time: pre, post) MANOVAs with repeated measures were applied to ascertain differences in gait parameters. RESULTS: A significant Time×Motor Complexity×Group interaction was found for AVG and CV. For AVG, JG showed improvements for flat and hurdling conditions in step length (flat: ∆=+2.6%, d=0.4; hurdling: ∆=+3.2%, d=0.4), gait cycle (flat: ∆=-4.3%, d=0.4; hurdling: ∆=-4.0%, d=0.5), speed (flat: ∆=+6.6%, d=0.7; hurdling: ∆=+6.7%, d=0.6) and cadence (flat: ∆=4.3%, d=0.4; hurdling: ∆=3.9%, d=0.5). For CV, JG improved step length for flat (∆=-20.9%, d=0.6) and hurdling (∆=-16.3%, d=0.8) conditions, whereas CG showed a deterioration in the step length for the corridor condition (∆=+22.3%, d=0.7). CONCLUSIONS: The findings demonstrated the effectiveness of an adapted judo program for improving gait performance in older individuals, suggesting a potential protective effect for fall risk.

Energy Balance and Active Lifestyle: Potential Mediators of Health and Quality of Life Perception in Aging.

The relationship between aging and perception of health and quality of life is complex and its mediation mechanisms need to be further explored. The purpose of this study was to investigate the mediating effects of total energy expenditure and intake, body mass, and body image dissatisfaction on the relationship between age and perception of health and quality of life. Forty-two senior athletes, 55 physically active, and 61 sedentary individuals (aged 55-84 years) were evaluated for total energy expenditure (EE), energy intake (EI), body mass index (BMI), absolute Body Dissatisfaction Index (BDIabx), and physical (PCS) and mental (MCS) health and quality of life perception. Multiple mediation analyses were applied to assess the relationship between age and PCS and MCS indices, through the mediators EE, EI, BMI, and BDIabx. For MCS, but not for PSC, the mediation analysis showed: (a) a direct effect of age; (b) a mediation path through EE, EI, BMI, and BDIabx; and (c) a positive total effect. The combination of positive and negative mediating effects influencing the mental health perception underlined that with advancing age, the maintenance of high levels of energy expenditure through physical activity could positively impact body image satisfaction and, in turn, mental health.

How Older Adults Cope with Cognitive Complexity and Environmental Constraints during Dual-Task Walking: The Role of Executive Function Involvement.

This cross-sectional study investigated the interactive dual-task (DT) effects of executive function demands and environmental constraints on older adults' walking and the moderating role of habitual physical activity (PA). Locomotor performance under different environmental constraints (flat versus obstructed walking) and cognitive performance with different executive function involvement (backward counting versus random number generation) were assessed under single-task (ST) and DT conditions in 135 participants (mean age 68.1 ± 8.4). The weekly number of daily steps was measured. Reciprocal DT effects of walking on cognitive performance and of the cognitive task on gait performance were computed and submitted to analyses of covariance with age, PA level, and cognitive functioning as covariates, followed by linear regressions with PA level as predictor. Cognitive task demands and environmental constraints individually and jointly affected gait variability (p = 0.033, ηp2 = 0.08) and executive function performance (p = 0.009, ηp2 = 0.09). Physical activity level predicted a low but significant percentage of variance of DT effects on gait only in flat walking (R2 = 0.04, p = 0.027). Results suggest that older individuals may adopt variable task prioritization in dual tasking depending on the type of executive function involvement and the environmental constraints on walking. Their DT ability was slightly affected by habitual PA.

Autonomic Stress Response and Perceived Effort Jointly Inform on Dual Tasking in Aging.

The study investigated, through neuroendocrinological, subjective and behavioral assessments, how aging individuals cope with locomotor-cognitive dual-tasking and whether physical activity habits influence the acute response to locomotor-cognitive performance. Seventy-nine healthy participants aged 55-85 years were assessed on locomotor (gait speed, stride length) and cognitive (working memory) performances under single- and dual-task (ST, DT) conditions, and habitual physical activity (daily steps). Rating of perceived exertion (RPE) was assessed immediately after performance. Salivary α-amylase (sAA) was measured prior, immediately and 5 min after performance. Gait and working memory variables, the area under the curve of sAA (AUC) and DT-ST differences (DT effects) were computed. AUC was higher when the ST or DT performance involved a locomotor component and showed a pre-to-post increment after DT only, whereas RPE was higher when performance involved a cognitive component. Daily steps neither predicted sAA, nor RPE. Associations between DT effects on sAA, RPE and performance emerged in high-active participants only. In aging individuals, DT walking elicits an autonomic stress response presumably led by the challenge to share resources relying upon common neural substrates. This autonomic response seems tuned to gait performance and subjective evaluation of effort in those more accustomed to walking.