The effect of dual-task training on postural and cognitive performances in adolescents with down syndrome.

BACKGROUND: The dual task training (DTT) has been shown to improve postural and cognitive performances in many populations. Therefore, it seems of interest to explore the effect of such training modality in individuals with Down syndrome (DS) presenting both cognitive and postural deficits. AIMS: This study explored the effect of a DTT compared to a single task training (STT) on postural and cognitive performances in adolescents with DS. METHODS AND PROCEDURES: The center of pressure velocity (CoPVm) and the cognitive performance in the selective word recall test were recorded under single task (ST) and DT conditions before and after 8 weeks in the STT group (STTG), the DTTG and the control group (CG). OUTCOMES AND RESULTS: Before training, CoPVm values increased and cognitive performances decreased (p < 0.001) during the DT compared to ST conditions in all groups. After training, CoPVm decreased (p < 0.001) in the DTTG and the STTG under the ST conditions. However, under DT conditions, these values decreased (p < 0.001) only in the DTTG. The cognitive performance increased (p < 0.001) only in the DTTG in both ST and DT conditions. CONCLUSION: The DTT is strongly recommended to improve both postural and cognitive performances in individuals with DS notably in DT conditions.

Effects of Specific Dual Task Training on Change of Direction Ability, Cognitive Flexibility, and Inhibition in Young Soccer Players.

In the current study we aimed to investigate the effect of specific dual task training (SDTT) compared to conventional soccer training (CST) on motor and cognitive performances in U13 elite soccer players. Twenty-four young soccer players (all males) participated in this study. We measured their change of direction ability (CODA) and cognitive performances (cognitive flexibility and inhibition) before and after four weeks in either the SDTT group or the CST group. We administered the Trail-Making Test (TMT) to evaluate cognitive flexibility and the Stroop test to evaluate cognitive inhibition. We assessed CODA using the t test (TT). After training, CODA (p < .001), cognitive flexibility (p < .001), and inhibition (p < .001) were improved only in the SDTT group. These results suggest that SDTT seems more suitable than CST to optimally improve both CODA and cognitive performances in U13 elite soccer players.

Do Motor-Cognitive and Motor-Motor Dual-Task Training Differently Affect Dual-Task Interference in Individuals With Intellectual Disability?

This study explored the effect of different dual-task (DT) training programs on DT interference in adults with intellectual disability. Center-of-pressure (CoP) mean velocity in single-task (ST) and cognitive-DT conditions and the Timed Up-and-Go Test (TUGT) during ST, cognitive-DT, and motor-DT conditions were assessed before and after intervention in a cognitive-motor training group, a motor-motor training group, and a control group. Before training, CoP mean velocity and TUGT time increased (p < .001) in DT compared with the ST condition. After training, the CoP mean velocity values remained unchanged (p = .07) in DT compared with the ST condition among the cognitive-motor training group. Furthermore, compared with the ST condition, no increase (p = 1) was reported in the TUGT time during the cognitive-DT condition for the cognitive-motor training group and during the motor-DT for the motor-motor training group (p = .12). The effect of DT training on DT interference depends on the training modality.

Time Limited Benefits of Physical and Proprioceptive Training on Physical Fitness Components in Children With Autism Spectrum Disorders.

In this study, we explored the immediate and three-month follow-up effects of physical training on physical fitness in children with autism spectrum disorder (ASD). We randomly assigned 20 children with ASD (age 8-11 years) into an experimental group (EG; n = 10) and a control group (CG; n = 10). The EG participated in an 8-week training program involving both strength and proprioceptive exercises (three 60-minute sessions/week), while the CG simply maintained their daily activities. We assessed physical fitness components for each participant at baseline, post-training, and at a 3-month follow-up. The physical training intervention significantly improved physical fitness of these children with ASD in terms of their flexibility (p < .001; 32.46%), lower limbs strength (p = .003; 36.98%), lower body power (p < .001; 41.78%) and functional mobility (p < .001; 25.56%). However, these addition training-induced gains were lost at follow-up for lower limbs strength (p < .001), flexibility (p < .001), and functional mobility (p = .034)). Physical training was effective for improving physical fitness in children with ASD, but the loss of these gains at three months follow-up underscored the need for continuous physical exercise.

Impact of neuromuscular training including balance, strength and plyometric exercises on static and dynamic balance in high-level male runners with mild intellectual disability.

BACKGROUND: This study aims to investigate the impact of neuromuscular training (NMT) on static and dynamic postural balance (PB) among high-level male runners with intellectual disability. METHOD: Twenty-seven runners were randomly assigned to a NMT group and a control group who maintained their conventional training. Static and dynamic PB were assessed using the centre of pressure (CoP) excursions (in bipedal and unipedal stances under open eyes (OE) and closed eyes (CE) conditions) and the star excursion balance test (SEBT), respectively, at pre-training and post-training. RESULTS: The NMT group showed significantly (p < 0.05) decreased CoP values and increased SEBT scores at post-training compared to pre-training. The switch from OE to CE did not affect static PB in the bipedal stance, only in the NMT group. CONCLUSIONS: The NMT was effective in improving static and dynamic PB in runners with intellectual disability. The NMT could reduce visual dependency.

Cognitive-motor interference during standing stance across different postural and cognitive tasks in individuals with Down syndrome.

BACKGROUND: Individuals with Down syndrome (DS) presented both cognitive and motor impairments that could influence each other. Therefore, exploring cognitive-motor interference during standing stance is relevant in this population. AIMS: This study explored the dual task (DT) effects on postural balance during diverse cognitive tasks and sensory manipulations in individuals with DS, compared to those with typical development (TD). METHODS AND PROCEDURES: Fifteen adolescents with DS (age = 14.26 ± 1.27 years; height = 1.50 ± 0.02; weight = 46.46 ± 4.03 kg; BMI =20.54 ± 1.51 kg/m2) and thirteen with TD (age = 14.07 ± 1.11 years; height = 1.50 ± 0.05; weight = 44.92 ± 4.15 kg; BMI =19.77 ± 0.94 kg/m2) participated in this study. Postural and cognitive performances for the selective span task (SST) and the verbal fluency (VF) were recorded during single task (ST) and DT conditions. Postural conditions were: firm eyes open (firm-EO), firm eyes closed (firm-EC) and foam-EO. Motor and cognitive DT costs (DTC) were calculated and analyzed across these different cognitive and postural conditions. OUTCOMES AND RESULTS: In the DS group, postural performance was significantly (p < 0.001) altered during all DT conditions, compared to the ST situation. Moreover, the motor DTC was significantly (p < 0.001) higher while performing the VF task than the SST. However, in the control group, postural performance was significantly (p < 0.001) impaired only while performing the VF test in the DT-Firm EO condition. For both groups, cognitive performances were significantly (p < 0.05) altered in all DT conditions compared to the ST one. CONCLUSION: Adolescents with DS are more prone to DT effects on postural balance than those with TD.

Dual-Task Training Effects on the Cognitive-Motor Interference in Individuals with Intellectual Disability.

This study explored the effect of dual task (DT) training compared to single task (ST) training on postural and cognitive performances in DT conditions in individuals with intellectual disability (ID). Postural sways and cognitive performances were measured separately and simultaneously before and after 8 weeks in the ST training group (STTG), the DT training group (DTTG) and the control group (CG) that did not received any training. Before training, postural sways and cognitive performances were higher in the DT condition compared to ST one in all groups. After training, postural sways were higher in the DT condition compared to the ST only in the STTG and the CG. The cognitive performance increased after training only in the DTTG.

Time Course Effects of Different Intensities of Running Exercise on Cognitive and Motor Performances in Individuals With Intellectual Disability.

This study explored the acute effects of different running intensities on cognitive and motor performances in individuals with intellectual disability (ID). An ID group (age, M = 15.25 years, SD = 2.76) and a control group without ID (age, M = 15.11 years, SD = 1.54) performed visual simple and choice reaction times, auditory simple reaction time, and finger tapping tests before and after running at low or moderate intensity (30% and 60% of heart rate reserve [HRR], respectively). Visual simple reaction time values decreased (p < .001) after both intensities at all time points with higher (p = .007) extend after the 60% HRR intensity for both groups. After both intensities, the VCRT decreased (p < .001) in the ID group at all time points compared with preexercise (Pre-EX) while, in the control group, these values decreased (p < .001) only immediately (IM-EX) and after 10 min (Post-10) of exercise cessation. Compared withs Pre-EX, in the ID group, the auditory simple reaction time values decreased (p < .001) at all time points after the 30% HHR intensity whereas, after the 60% HRR, these values decreased only at IM-EX (p < .001), Post-10 (p = .001) and Post-20 (p < .001). In the control group, auditory simple reaction time values decreased (p = .002) only after the 30% HRR intensity at IM-EX. The finger tapping test increased at IM-EX (p < .001) and at Post-20 (p = .001) compared to Pre-EX in both groups only after the 30% HHR intensity and for the dominant hand. The effect of physical exercise on cognitive performances in individuals with ID seems to depend on the cognitive test type as well as the exercise intensity.

Swimming, better than tennis, develops sensorimotor adaptabilities involved in postural balance in 5-6-year-old children.

PURPOSE: The present study aimed to evaluate the postural balance of young tennis players and young swimming practitioners in static and dynamic conditions. METHODS: Thirty-six children (5-6 years old) participated in 3 groups: 12 tennis players, 12 swimming practitioners and 12 controls. Static and dynamic [in medial lateral (ML) and anterior posterior (AP) planes] postural balance were assessed by the centre of pressure sways using a stabilometric force platform in the eyes opened (EO) and eyes closed (EC) conditions. RESULTS: In the EO condition, swimming practitioners and tennis players had a significantly lower (p < 0.05) centre of pressure mean velocity (CoPVm) compared to controls in both static and dynamic medial-lateral (D-ML) postures. In the D-ML posture, swimming practitioners showed lower CoPVm compared to tennis players. However, in the EC condition, only the swimming practitioners showed better static and D-ML postural balance (p < 0.05) compared to their counterparts. In the static posture, the Romberg index value was significantly higher (p < 0.05) in tennis players compared to the two other groups. CONCLUSION: Tennis players developed a higher reliance on vision to maintain balance, whereas swimming practitioners were more stable in challenging postural conditions. Clinicians should consider incorporating swimming training rather than tennis as an appropriate balance training in fall-prevention programs.

Dual-task affects postural balance performance in children with intellectual disability.

BACKGROUND: Dual-task designs have been used to study the degree of automatic and controlled processing involved in postural balance. The aim of the present study was to explore postural balance performance during dual-task condition in children with intellectual disability compared to those with typical development. METHODS: Fifteen children with intellectual disability aged from 7 to 12 years old and fifteen age-matched children with typical development participated in this study. Participants were asked to maintain static balance on a force platform during a baseline condition (single task) and while performing the Picture Recognition Memory Test (dual-task condition). RESULTS: The results showed that dual-task similarly affects postural performance of both typically developing children and those with intellectual disability (p < .001). CONCLUSIONS: Children with intellectual disability and children with typical development have difficulties in maintaining their balance when carrying out a concurrent cognitive task. Intellectual disability did not lead to a more strongly compromised balance performance in dual-task situation.

Acute effects of aerobic versus resistance exercises on cognitive function in individuals with intellectual disability.

BACKGROUND: This study compared the acute effects of aerobic (AE) and resistance (RE) exercise on reaction time (RT) and working memory (WM) in individuals with intellectual disability. METHODS: RT tests and Corsi test for WM were performed before and after three intervention sessions: AE, RE, or control session consisting on watching video. RESULTS: The RT values decreased significantly (p < .001) after both of AE and RE with higher extend after the RE but did not vary following the control session. Corsi scores increased significantly (p < .001) after AE but not after RE or control session. CONCLUSIONS: These findings suggest that the effects of acute exercise on cognitive function in individuals with intellectual disability depend on the exercise mode as well as the nature of the cognitive task. The RE seems to be more recommended for RT enhancement whereas only the aerobic one could improve WM in these individuals.

Effects of Music Listening on Postural Balance in Adolescents with Visual Impairment.

We aimed to investigate the effect of music on visually impaired adolescents' postural balance across different somatosensory and vestibular input conditions. We recruited 19 adolescent participants (9 males, 10 females) with severe congenital visual impairment. We recorded their mean center of pressure velocity (CoPVm) during static upright bipedal standing under somatosensory (firm and foam surfaces) and vestibular (head facing forward (HFF), head rotated 90° to the right (HRR), and head rotated 90° to the left (HRL)) perturbations in three auditory conditions (no-music, listening to Jupiter, and listening to their preferred music). We found that CoPVm decreased significantly when listening to both Jupiter and preferred music, compared to the no-music condition on both firm (p < .05) and foam (p < .001) surfaces and with the HFF (p < .05), rotated to the right (p < .001) or rotated to the left (p < .001). Moreover, CoPVm values increased significantly with somatosensory manipulation (p < .001) in all the auditory conditions and with vestibular manipulation (p < .01) only in the no-music condition. We concluded that listening to both Jupiter and preferred music improved postural balance in visually impaired adolescents, even in challenged postural conditions.

Different types of combined training programs to improve postural balance in single and dual tasks in children with intellectual disability.

The study explored the effects of two combined training (Strength-Proprioceptive versus Cognitive-Balance) programs on postural balance during single-task and dual-task conditions in children with intellectual disability. The postural balance and the second cognitive-task performances were evaluated before and after 8-week of training in two groups: Strength-Proprioceptive Group (n = 12) and Cognitive-Balance Group (n = 10). Results showed that, in both groups and regardless of the training effect, the postural balance performance was significantly (p < 0.05) altered in the dual-task condition compared to the single-task one. After-training session, postural balance performance was improved significantly (p < 0.001) for all task conditions. After training session, the second cognitive-task performance was improved in the Strength-Proprioceptive Group (p < 0.001) and Cognitive-Balance Groupe (p < 0.05). In conclusion, the combined training programs, Strength-Proprioceptive and Cognitive-Balance, improved postural balance performance in single-task and dual-task conditions in children with intellectual disability.

Cognitive-Motor Interference during Dual Tasks in Blind Children.

The aim of the present study was to compare the dual-task (DT) performance in blind children with sighted ones while concurrently performing a motor task (upright standing) with cognitive (Letter fluency (LF) or Category fluency (CF)) tasks. The Center of pressure mean velocity (CoPVm) and the cognitive performances were recorded during single (ST) and DT conditions. Results showed that, for both groups, CoPVm values increased significantly (p < 0.05) in the DT compared to ST condition. The CoPVm values were significantly (p < 0.001) higher in blind children, compared to controls only in the DT-CF condition. In conclusion, balance performance of blind and typically developed children is affected by dual tasking. Interference between motor and cognitive tasks has more pronounced effects on balance performance in blind children, compared to controls. This difference was observed only when performing the CF task concurrently with the postural balance task.

Physical, Biochemical, and Neuromuscular Responses to Repeated Sprint Exercise in Eumenorrheic Female Handball Players: Effect of Menstrual Cycle Phases.

ABSTRACT: Graja, A, Kacem, M, Hammouda, O, Borji, R, Bouzid, MA, Souissi, N, and Rebai, H. Physical, biochemical, and neuromuscular responses to repeated sprint exercise in eumenorrheic female handball players: effect of menstrual cycle phases. J Strength Cond Res 36(8): 2268-2276, 2022-Very few studies have been interested in the relationship between ovarian hormones and physiological function in female athletes. The aim of this study was to assess the effect of menstrual phases (MP) on physical, neuromuscular, and biochemical responses after repeated sprint exercise (RSE) in female handball players. Ten eumenorrheic athletes (22.5 ± 1.5 years, 1.70 ± 0.04 m) participated in 3 study visits (follicular phase [FP], luteal phase [LP], and premenstrual phase [PMP]). During each MP, they performed 20 × 5-second cycle sprints interspersed with 25 seconds of rest. Maximal voluntary contraction (MVC) tests of the knee extensor muscles at 90° of knee flexion were performed before and after RSE. Peak force and electromyography (EMG) signals were measured during the MVC tests. Blood samples were collected before and 3 minutes after each session. The percentage of decrement in peak power output over the 20 × 5-second cycle test (i.e., fatigue index) calculated between sprints 1 and 20 decreased significantly during PMP (-43.3% ± 5.7%) but not in LP (-39.2% ± 7.7%) compared with FP (-32.44% ± 6.3%) ( p < 0.05). Moreover, no significant difference was found between MP in all frequency components of EMG before RSE ( p > 0.05). Maximal voluntary contraction, neuromuscular efficiency, and median frequency values of vastus lateralis and rectus femoris were significantly decreased in PMP compared with FP and LP ( p < 0.05). Creatine kinase (CK) levels were significantly higher in PMP compared with FP and LP after RSE ( p < 0.05). These findings suggest that RSE induces more peripheral fatigue associated with muscle damage in PMP. This might be attributable to hormonal variation across MP. Therefore, FP seems to be the right time for intense training to improve strength performance.

The Disturbing Effect of Neuromuscular Fatigue on Postural Control Is Accentuated in the Premenstrual Phase in Female Athletes.

This study explored the fatigue effect on postural control (PC) across menstrual cycle phases (MCPs) in female athletes. Isometric maximal voluntary contraction (IMVC), the center of pressure sway area (CoParea), CoP length in the medio-lateral (CoPLX) and antero-posterior (CoPLY) directions, and Y-balance test (YBT) were assessed before and after a fatiguing exercise during the follicular phase (FP), mid-luteal phase (LP), and premenstrual phase (PMP). Baseline normalized reach distances (NRDs) for the YBT were lower (p = 0.00) in the PMP compared to others MCPs, but the IMVC, CoParea, CoPLX, and CoPLY remained unchanged. After exercise, the IMVC and the NRD decrease was higher at PMP compared to FP (p = 0.00) and LP (p = 0.00). The CoParea, CoPLX, and CoPLY increase was higher in the PMP compared to FP (p = 0.00) and LP (p = 0.00). It was concluded that there is an accentuated PC impairment after exercise observed at PMP.

Time-of-day effects on the postural control and symptoms in women with rheumatoid arthritis.

The present study was designed to assess time-of-day effects on postural balance and symptoms of rheumatoid arthritis (RA) patients. A total of 15 American College of Rheumatology functional class I and II RA patients and 15 healthy controls aged between 45 and 55 (mean age: 50 ± 3) years of age voluntarily participated. We conducted a case-control, repeated-measures in design study. Postural balance, axillary temperature, pain intensity, fatigue, and sleepiness were measured during five test sessions at 06:00, 10:00, 14:00, 18:00, and 22:00 h. Participants were randomized to the order of test sessions, and each session was separated by >36 hours to minimize/eliminate learning effects. Center of pressure area (CoParea) (p < .001), pain (p < .01), and sleepiness (p < .05) values were significantly higher at 06:00 and 22:00 h compared to 10:00, 14:00, and 18:00 h in the RA group. Fatigue significantly increased (p < .05) at 22:00 h in comparison to 10:00, 14:00, and 18:00 h in the RA group. Axillary temperature was significantly (p < .001) lower at 06:00 and at 22:00 h compared to 10:00, 14:00, and 18:00 h in the RA group. In the control group, there were no significant time-of-day difference in fatigue, but axillary temperature was significantly lower (p < .01) at 06:00 h compared to 10:00 h, 14:00, 18:00, and 22:00 h, sleepiness values were significantly higher (p < .05) at 06:00 and 22:00 h compared to 10:00, 14:00, and 18:00 h, and revealed CoParea values were significantly (p < .05) higher at 06:00 h compared to 14:00 h. Finally, in the RA group, significant correlations were found between values of CoParea and pain (r = 0.47; p < .001), sleepiness (r = 0.39; p < .01), fatigue (r = -0.46; p < .001), and also axillary temperature (r = -0.35; p < .001). Multiple linear regression analysis further indicated that in the RA group, time-of-day variation in postural balance was predicted collectively by that in pain and fatigue (30.7%) (R2 = 0.307; F = 11.53; p < .001). Our results first suggest that time-of-day significantly affects postural balance, axillary temperature, pain intensity, fatigue, and sleepiness in RA patients and second that the temporal variation observed in pain, fatigue, and somnolence are concomitant with that observed in postural balance.Abbreviations: RA: Rheumatoid arthritis; H&O questionnaire: Horne and Ostberg questionnaire; PSQI: Pittsburgh sleep quality index; HAQ: Health assessment questionnaire; SF-36: the short form-36; WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index; CoP: The Center of foot Pressure; CoParea: The Center of foot Pressure area; VAS: The Visual Analogue Scale; KSS: Karolinska Sleepiness Scale.

Neuromuscular Fatigue in Individuals With Intellectual Disability: Comparison Between Sedentary Individuals and Athletes.

The authors explored neuromuscular fatigue in athletes with intellectual disability (AID) compared with sedentary individuals with intellectual disability (SID) and individuals with typical development. Force, voluntary activation level, potentiated resting twitch, and electromyography signals were assessed during isometric maximal voluntary contractions performed before and immediately after an isometric submaximal exhaustive contraction (15% isometric maximal voluntary contractions) and during recovery period. AID presented shorter time to task failure than SID (p < .05). The three groups presented similar isometric maximal voluntary contraction decline and recovery kinetic. Both groups with intellectual disability presented higher voluntary activation level and root mean square normalized to peak-to-peak M-wave amplitude declines (p < .05) compared with individuals with typical development. These declines were more pronounced in SID (p < .05) than in AID. The AID recovered their initial voluntary activation level later than controls, whereas SID did not. SID presented lower potentiated resting twitch decline compared with AID and controls with faster recovery (p < .05). AID presented attenuated central fatigue and accentuated peripheral fatigue compared with their sedentary counterparts, suggesting a neuromuscular profile close to that of individuals with typical development.

Time of day effect on balance performance, functional capacities and risk of fall in women with rheumatoid arthritis.

Objective: This study explored the time of day effect of balance performance, functional capacities and risk of fall in three different times in patients with rheumatoid arthritis (RA) and the association between these variations and those of RA symptoms.Methods: A "discontinual" protocol, composed of three test sessions, carried out at 6 am, 2 pm and 10 pm was set up, in order to investigate the time of day effect of balance performance, functional capacities, risk of fall, stiffness, range of motion, swollen and painful joints in women with RA.Results: Time Up and Go Test (TUGT), Functional Reach Test (FRT) and tinetti test scores were significantly higher (p < .01) at 6 am and at 10 pm compared to 2 pm. Stiffness, range of motion, swollen and painful joints values were significantly higher (p < .01) at 6 am and at 10 pm compared to 2 pm. A significant difference was observed on the stiffness, range of motion and swollen joints values between 6 am and 10 pm that were higher at 6 am (p < .05).Using Pearson's coefficient, correlations were found between RA symptom values; and TUGT, FRT and Tinetti test scores.Conclusion: Results showed a time of day effect of balance performance, functional capacities and risk of falls in women with RA. This variation indicates an alteration of performance at 6 am and 10 pm. Fluctuations of stiffness, limited range of motion, swollen and painful joints noted are concomitant to those of balance performance, functional capacities, and risk of fall.Abbreviations: RA: rheumatoid arthritis; H&O questionnaire: Horne and Ostberg questionnaire; PSQI: Pittsburgh sleep quality index; HAQ: health assessment questionnaire; SF-36: the short form-36; WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index; TUGT: Time Up and Go Test; FRT: Functional Reach Test.

Using a dual-task paradigm to investigate motor and cognitive performance in children with intellectual disability.

BACKGROUND: The purpose of the current study was to evaluate the effects of dual-task (DT) constraints on walking performance in children with intellectual disability (ID). METHODS: Fifteen children with intellectual disability and fifteen age-matched typically developed children were asked to walk at a preferred speed: along a path (baseline condition), while carrying a glass of water and while quoting animal names. RESULTS: The present study findings showed that DTs affect walking performance of both typically developed children and those with intellectual disability. In children with intellectual disability, DT walking decrements were significantly higher when performing a concurrent motor task than cognitive one. CONCLUSIONS: DT constraints with a secondary motor or cognitive tasks seemed challenging for children with intellectual disability suggesting that future treatments or assessments should consider using DT constraints to manipulate the difficulty of tasks.