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1.
Biol Sport ; 39(3): 735-743, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35959317

RESUMO

To assess the effects of a taper combined with proactive recovery on the repeated high intensity effort (RHIE) of elite rugby union players, and the possible interaction of pre-taper fatigue and sleep. Eighteen players performed a 3-week intensive training block followed by a 7-day exponential taper combined with a multicomponent recovery strategy. Following the intervention, players were divided into 3 groups (Normal Training: NT, Acute Fatigue: AF or Functional Overreaching: F-OR) based on their readiness to perform prior to the taper. Total sprint time [TST], percentage decrement [%D] and the number of sprints ≥90% of the best [N90] were analyzed to assess performance during a RHIE test. Subjective sleep quality was assessed through the Pittsburg Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS). No improvement in TST was reported in either NT or F-OR after the taper, whereas AF tended to improve (-1.58 ± 1.95%; p > 0.05; g = -0.20). F-OR players reported baseline PSQI and ESS indicative of sleep disturbance (6.2 ± 2.2 and 10.6 ± 5.4, respectively). AF displayed a small impairment in PSQI during intensive training (11.5 ± 80.6%; p > 0.05; g = 0.20), which was reversed following the taper (-34.6 ± 62.1%; p > 0.05; g = -0.73). Pre-taper fatigue precluded the expected performance benefits of the combined taper and recovery intervention, likely associated with a lack of strictly controlled intensive training block. Poor sleep quality before the intensive training period appeared to predispose the players to developing functional overreaching.

2.
J Strength Cond Res ; 35(Suppl 2): S111-S118, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34846332

RESUMO

ABSTRACT: Dong, L, Paradelo, D, Delorme, A, Oliveira, J, Parillo, B, Croteau, F, Romeas, T, Dubé, E, Bieuzen, F, Billaut, F, and Berryman, N. Sport-specific agility and change of direction in water polo: The reliability and validity of two newly developed tests. J Strength Cond Res 35(12S): S111-S118, 2021-There is a gap in water-based agility testing that considers both the change-of-direction (COD) and perceptive-reactive components of agility. This study sought to develop easily implementable, sport-specific in-water agility tests for water polo and to verify the reliability and validity of these new tests: the in-water Stop and Go (SG) and Jump and Go (JG). Female water polo athletes at the Senior (n = 12, age = 22.1 ± 2.1 years), Junior (n = 19, age = 18.5 ± 1.0 years), and Youth (n = 11, age = 16.5 ± 0.8 years) national levels performed 3 trials of each of the SG, JG, and the existing Functional Test for Agility Performance (FTAP). Senior athletes performed an additional experimental session to assess reliability parameters. Relative reliability for agility and COD versions of the SG and JG was high or very high (intraclass correlation coefficient [ICC] = 0.76-0.95). For construct validity analyses, significant between-group differences for each of the new tests (p < 0.05) were found. In contrast, the FTAP was moderately reliable (ICC = 0.57) and was unsuccessful in discriminating between playing levels. Considering the favorable metrological properties of the SG and JG, their fidelity to in-game demands, and their accessible setups, these new tests represent viable options to implement at grassroots and elite levels for the assessment and training of water polo-specific agility.


Assuntos
Desempenho Atlético , Esportes Aquáticos , Adolescente , Adulto , Atletas , Etnicidade , Teste de Esforço , Feminino , Humanos , Reprodutibilidade dos Testes , Adulto Jovem
3.
Stress ; 22(6): 687-695, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31124397

RESUMO

This study aimed to examine in healthy older adults the effects of dance/movement training (DMT) on the cortisol awakening response (CAR), a marker of chronic stress. Forty participants (mean age = 67.45, 75% women) were randomized into three groups: DMT (n = 12) - a set of exercises to promote gross motor skills, body awareness, and socialization; aerobic exercise training (AT; n = 14) - high intensity activity on a recumbent bicycle, and wait list (WL; n = 14). Both DMT and AT groups were supervised by licensed instructors and met three times a week for three months. Before and after their respective program, participants of all groups provided saliva samples on 3 d at 0-, 30- and 60-min after awakening, and had their fitness level evaluated. A significant group × time interaction (F(2,34) = 5.79, p = .01, η2partial = 0.25) was found, with the DMT group showing lower salivary cortisol values post-training, while the other two groups showed no change from baseline in their CAR. Cardiorespiratory fitness improved only in the AT group, while DMT showed no group-specific physical functioning improvements. The results are discussed in terms of the importance of physical and psychological effects of training on change in cortisol levels.


Assuntos
Dança/fisiologia , Hidrocortisona/metabolismo , Idoso , Exercício Físico/psicologia , Feminino , Nível de Saúde , Humanos , Masculino , Saliva , Estresse Psicológico
4.
BMC Geriatr ; 18(1): 93, 2018 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-29661156

RESUMO

BACKGROUND: Physical exercise, cognitive training, and vitamin D are low cost interventions that have the potential to enhance cognitive function and mobility in older adults, especially in pre-dementia states such as Mild Cognitive Impairment (MCI). Aerobic and progressive resistance exercises have benefits to cognitive performance, though evidence is somewhat inconsistent. We postulate that combined aerobic exercise (AE) and progressive resistance training (RT) (combined exercise) will have a better effect on cognition than a balance and toning control (BAT) intervention in older adults with MCI. We also expect that adding cognitive training and vitamin D supplementation to the combined exercise, as a multimodal intervention, will have synergistic efficacy. METHODS: The SYNERGIC trial (SYNchronizing Exercises, Remedies in GaIt and Cognition) is a multi-site, double-blinded, five-arm, controlled trial that assesses the potential synergic effect of combined AE and RT on cognition and mobility, with and without cognitive training and vitamin D supplementation in older adults with MCI. Two-hundred participants with MCI aged 60 to 85 years old will be randomized to one of five arms, four of which include combined exercise plus combinations of dual-task cognitive training (real vs. sham) and vitamin D supplementation (3 × 10,000 IU/wk. vs. placebo) in a quasi-factorial design, and one arm which receives all control interventions. The primary outcome measure is the ADAS-Cog (13 and plus modalities) measured at baseline and at 6 months of follow-up. Secondary outcomes include neuroimaging, neuro-cognitive performance, gait and mobility performance, and serum biomarkers of inflammation (C reactive protein and interleukin 6), neuroplasticity (brain-derived neurotropic factor), endothelial markers (vascular endothelial growth factor 1), and vitamin D serum levels. DISCUSSION: The SYNERGIC Trial will establish the efficacy and feasibility of a multimodal intervention to improve cognitive performance and mobility outcomes in MCI. These interventions may contribute to new approaches to stabilize and reverse cognitive-mobility decline in older individuals with MCI. TRIAL REGISTRATION: Identifier: NCT02808676. https://www.clinicaltrials.gov/ct2/show/NCT02808676 .


Assuntos
Cognição/fisiologia , Disfunção Cognitiva/reabilitação , Suplementos Nutricionais , Terapia por Exercício/métodos , Tolerância ao Exercício/fisiologia , Marcha/fisiologia , Treinamento Resistido/métodos , Idoso , Idoso de 80 Anos ou mais , Disfunção Cognitiva/psicologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
5.
Aging Clin Exp Res ; 30(8): 921-925, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29235076

RESUMO

BACKGROUND: Spontaneous walking speed (SWS) is one of the most important indicators of health in older adults. Studies have shown benefits of physical trainings on SWS in older adults but the impact of cognitive training and multidomain interventions remains understudied. AIMS: This original study aimed at comparing the impact of aerobic/resistance exercise, computerized cognitive training and the combination of both interventions compared with active control conditions on SWS in healthy older adults. METHODS: Ninety community-dwelling older adults were randomly assigned to four different combinations composed of two active interventions: physical aerobic/resistance and cognitive dual-task trainings, and two active control conditions: stretching exercises and computer lessons. The four combinations were the following: (1) aerobic/resistance and cognitive dual task (n = 28), (2) aerobic/resistance and computer lessons (n = 21), (3) stretching exercises and cognitive dual task and (n = 23), (4) stretching exercises and computer lessons (n = 18). Training sessions were held three times/week for three months. SWS for 30 s was assessed before and after the intervention. RESULTS: Repeated-measures ANOVA showed a main effect of time and a significant three-way interaction suggesting differential improvement in SWS according to training combinations. A clinical meaningful improvement in SWS was observed in groups 1-3 (0.08-0.14 m/s; effect sizes: small to moderate) but not in the active control group 4. DISCUSSION: Results of this study suggest that aerobic/resistance exercise and computerized dual-task training are two non-pharmacological interventions by which SWS, a functional vital sign, can be clinically improved in older adults. CONCLUSION: This original study pointed out different tools to prevent functional decline in older people.


Assuntos
Terapia por Exercício/métodos , Exercício Físico/fisiologia , Treinamento Resistido/métodos , Velocidade de Caminhada/fisiologia , Idoso , Idoso de 80 Anos ou mais , Cognição/fisiologia , Feminino , Humanos , Vida Independente , Masculino , Pessoa de Meia-Idade
6.
Eur J Appl Physiol ; 117(1): 53-59, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27815704

RESUMO

PURPOSE: Gait speed is associated with survival in older adults and it was suggested that an elevated energy cost of walking (Cw) is an important determinant of gait speed reduction. Thus far, little is known about the factors that contribute to a lower Cw but it was shown that lower body strength training could reduce the Cw. Therefore, the objective of this study was to investigate the relationship between lower body strength and the Cw in a cohort of healthy older adults. METHODS: A total of 48 participants were included in this study (70.7 ± 5.4 years). After a geriatric and a neuropsychological assessment, participants underwent a fitness testing protocol which included a maximal oxygen uptake test, assessment of the Cw at 4 km h-1 on a treadmill, an isokinetic maximal strength test for the ankle, knee and hip joints and a body composition assessment. Relationships between strength variables and the Cw were assessed with partial correlations and linear regression analyses. RESULTS: Hip extensors and hip flexors peak torque was significantly correlated with the Cw (r = -0.36 and -0.32, respectively; p < 0.05). A tendency towards significance was identified for the ankle plantar flexors (r = -0.25, p = 0.09). Hip extensors peak torque was the only significant neuromuscular parameter included in the linear regression analysis (p < 0.05). CONCLUSION: These results show that hip extensors are an important muscle group with regards to the Cw measured on a treadmill in this cohort of healthy older adults.


Assuntos
Metabolismo Energético , Força Muscular , Músculo Esquelético/fisiologia , Consumo de Oxigênio , Caminhada , Idoso , Estudos Cross-Over , Feminino , Marcha , Humanos , Perna (Membro)/fisiologia , Masculino , Músculo Esquelético/metabolismo , Distribuição Aleatória
7.
J Sports Sci Med ; 15(1): 126-30, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26957935

RESUMO

The purpose of the study was to determine whether total work measured during a high intensity isokinetic fatigue test (TWFAT) could be considered as a valid measure of anaerobic work capacity (AWC), such as determined by total work measured during a Wingate Anaerobic Test (TWWAnT). Twenty well-trained cyclists performed 2 randomly ordered sessions involving a high intensity isokinetic fatigue test consisting in 30 reciprocal maximal concentric contractions of knee flexors and extensors at 180°·s(-1), and a Wingate Anaerobic Test. We found that TWFAT of knee extensors was largely lower than TWWAnT (4151 ± 691 vs 22313 ± 2901 J, respectively, p < 0.05, Hedge's g = 4.27). Both measures were highly associated (r = 0.83), and the 95% limits of agreement (LoA) represented 24.5% of TWWAnT. TWFAT of knee flexors (2151 ± 540 J) was largely lower than TWWAnT (p < 0.05, g = 9.52). By contrast, both measures were not associated (r = 0.09), and the 95% LoA represented 31.1% of TWWAnT. Combining TWFAT of knee flexors and knee extensors into a single measure (6302 ± 818 J) did not changed neither improved these observations. We still found a large difference with TWWAnT (p < 0.05, g = 5.26), a moderate association (r = 0.65) and 95% LoA representing 25.5% of TWWAnT. We concluded that TWFAT of knee extensors could be considered as a valid measure of AWC, since both measure were highly associated. However, the mean difference between both measures and their 95% LoA were too large to warrant interchangeability. Key pointsTotal work performed during a high intensity isokinetic fatigue test can be considered as a valid measure of anaerobic work capacity (as determined by total work performance during a 30-s Wingate anaerobic test).The 95% limits of agreement are two large to allow a direct comparison between both measures. In other words, it is not possible to estimate the magnitude of performance improvement during a 30-s Wingate anaerobic test from that observed during a high intensity isokinetic fatigue test.In addition to provide sport scientists and coaches with measures of peak torque and ratios between agonists and antagonists muscles in a perspective of injury prevention, isokinetic dynamometry can also be used in the physiological assessment of athletes. However, some precautions should be taken in the interpretation of data.

8.
JAMA Netw Open ; 6(7): e2324465, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37471089

RESUMO

Importance: Exercise, cognitive training, and vitamin D may enhance cognition in older adults with mild cognitive impairment (MCI). Objective: To determine whether aerobic-resistance exercises would improve cognition relative to an active control and if a multidomain intervention including exercises, computerized cognitive training, and vitamin D supplementation would show greater improvements than exercise alone. Design, Setting, and Participants: This randomized clinical trial (the SYNERGIC Study) was a multisite, double-masked, fractional factorial trial that evaluated the effects of aerobic-resistance exercise, computerized cognitive training, and vitamin D on cognition. Eligible participants were between ages 65 and 84 years with MCI enrolled from September 19, 2016, to April 7, 2020. Data were analyzed from February 2021 to December 2022. Interventions: Participants were randomized to 5 study arms and treated for 20 weeks: arm 1 (multidomain intervention with exercise, cognitive training, and vitamin D), arm 2 (exercise, cognitive training, and placebo vitamin D), arm 3 (exercise, sham cognitive training, and vitamin D), arm 4 (exercise, sham cognitive training, and placebo vitamin D), and arm 5 (control group with balance-toning exercise, sham cognitive training, and placebo vitamin D). The vitamin D regimen was a 10 000 IU dose 3 times weekly. Main Outcomes and Measures: Primary outcomes were changes in ADAS-Cog-13 and Plus variant at 6 months. Results: Among 175 randomized participants (mean [SD] age, 73.1 [6.6] years; 86 [49.1%] women), 144 (82%) completed the intervention and 133 (76%) completed the follow-up (month 12). At 6 months, all active arms (ie, arms 1 through 4) with aerobic-resistance exercise regardless of the addition of cognitive training or vitamin D, improved ADAS-Cog-13 when compared with control (mean difference, -1.79 points; 95% CI, -3.27 to -0.31 points; P = .02; d = 0.64). Compared with exercise alone (arms 3 and 4), exercise and cognitive training (arms 1 and 2) improved the ADAS-Cog-13 (mean difference, -1.45 points; 95% CI, -2.70 to -0.21 points; P = .02; d = 0.39). No significant improvement was found with vitamin D. Finally, the multidomain intervention (arm 1) improved the ADAS-Cog-13 score significantly compared with control (mean difference, -2.64 points; 95% CI, -4.42 to -0.80 points; P = .005; d = 0.71). Changes in ADAS-Cog-Plus were not significant. Conclusions and Relevance: In this clinical trial, older adults with MCI receiving aerobic-resistance exercises with sequential computerized cognitive training significantly improved cognition, although some results were inconsistent. Vitamin D supplementation had no effect. Our findings suggest that this multidomain intervention may improve cognition and potentially delay dementia onset in MCI. Trial Registration: ClinicalTrials.gov Identifier: NCT02808676.


Assuntos
Disfunção Cognitiva , Treino Cognitivo , Humanos , Feminino , Idoso , Masculino , Disfunção Cognitiva/terapia , Disfunção Cognitiva/psicologia , Cognição , Vitaminas/uso terapêutico , Vitaminas/farmacologia , Vitamina D/uso terapêutico , Vitamina D/farmacologia , Suplementos Nutricionais
9.
Eur J Appl Physiol ; 112(5): 1613-20, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21863296

RESUMO

We assessed whether the metabolic energy cost of walking was higher when measured overground or on a treadmill in a population of healthy older adults. We also assessed the association between the two testing modes. Participants (n = 20, 14 men and 6 women aged between 65 and 83 years of age) were randomly divided into two groups. Half of them went through the overground-treadmill sequence while the other half did the opposite order. A familiarization visit was held for each participant prior to the actual testing. For both modes of testing, five walking speeds were experimented (0.67, 0.89, 1.11, 1.33 and 1.67 m s(-1)). Oxygen uptake was monitored for all walking speeds. We found a significant difference between treadmill and track metabolic energy cost of walking, whatever the walking speed. The results show that walking on the treadmill requires more metabolic energy than walking overground for all experimental speeds (P < 0.05). The association between both measures was low to moderate (0.17 < ICC < 0.65), and the standard error of measurement represented 6.9-15.7% of the average value. These data indicate that metabolic energy cost of walking results from a treadmill test does not necessarily apply in daily overground activities. Interventions aiming at reducing the metabolic energy cost of walking should be assessed with the same mode as it was proposed during the intervention. If the treadmill mode is necessary for any purposes, functional overground walking tests should be implemented to obtain a more complete and specific evaluation.


Assuntos
Metabolismo Energético/fisiologia , Teste de Esforço , Consumo de Oxigênio/fisiologia , Caminhada/fisiologia , Idoso , Idoso de 80 Anos ou mais , Antropometria , Fenômenos Biomecânicos , Estudos Cross-Over , Feminino , Humanos , Masculino
10.
Int J Sports Physiol Perform ; 17(6): 871-878, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35259728

RESUMO

PURPOSE: To assess the effect of a rugby-specific high-intensity interval-training (HIITRugby) protocol on the repeated high-intensity-effort ability of young elite rugby union players and to verify the influence of 2 preconditioning sequences composed either of physical contacts (ie, tackles) or of additional runs on the magnitude of improvement. METHOD: Fourteen players (19 [1] y; 183.5 [8.6] cm; 95.6 [15.6] kg) underwent an HIITRugby protocol, consisting of 7 supervised training sessions over 4 weeks, each session including 3 or 4 sets of 1 to 2 minutes with 1-minute recovery. Prior to HIITRugby training, players underwent a preconditioning contact sequence or a preconditioning running sequence, to assess their influence on subsequent interval-training sessions. RESULTS: The overall group showed a moderate improvement in total sprint time, sprints ≥90% of the best, and 20-m sprint (-3.91% [2.68%], P = .0002; 74.6% [123.7%], P = .012; -3.22% [3.13%], P = .003, respectively) and a large improvement in percentage decrement (-23.1% [20.5%], P = .005) following the 4-week training block. Relative improvements were similar between groups in total sprint time, 20-m sprint, and perceived difficulty, but the preconditioning running-sequence group exhibited a larger magnitude of gains in percentage decrement (-28.6% [20.2%] vs -17.6% [20.7%]; effect size = -1.01 vs -0.73). CONCLUSION: An HIITRugby training block was effective to improve repeated high-intensity-effort ability. A preconditioning contact sequence prior to HIITRugby can reduce subsequent long-interval running activity, which may attenuate the improvement of repeated high-intensity-effort indices related to the aerobic system.


Assuntos
Desempenho Atlético , Futebol Americano , Treinamento Intervalado de Alta Intensidade , Corrida , Humanos , Rugby
11.
Artigo em Inglês | MEDLINE | ID: mdl-36613083

RESUMO

The application of interventions to enhance mobility in ecological settings remain understudied. This study was developed to evaluate the feasibility of training methods in a community centre and to evaluate their impact on mobility outcomes. Fifty-four participants were randomized to one of three 12-week training programs (three times/week): aerobic (AE), gross motor abilities (GMA) or cognitive (COG). Feasibility was evaluated by calculating adherence, feedback from participants and long-term participation. The impact of these interventions on mobility was assessed by comparing pre- and post-program on Timed-up-and-go (TUG) and spontaneous walking speed (SWS) performances. Results showed relatively high rates of adherence (85.1%) and long-term participation (66.7%), along with favorable feedbacks. SWS significantly improved in COG (0.10 ± 0.11 m.s-1; p = 0.004) and AE (0.06 ± 0.11 m.s-1; p = 0.017) groups, and TUG performance was maintained in all groups. Results of this feasibility study demonstrated successful implementation of physical and cognitive training programs, encouraging the development of real-world applications.


Assuntos
Exercício Físico , Velocidade de Caminhada , Humanos , Idoso , Estudos de Viabilidade , Cognição , Caminhada
12.
J Gerontol B Psychol Sci Soc Sci ; 77(6): 1069-1079, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34865009

RESUMO

OBJECTIVES: Studies suggest that cognitive training and physical activity can improve age-related deficits in dual-task performances. However, both of these interventions have never been compared in the same study. This article investigates the improvement in dual-task performance in 2 types of exercise training groups and a cognitive training group and explores if there are specific dual-task components that are more sensitive or more likely to improve following each type of training. METHODS: Seventy-eight healthy inactive participants older than the age of 60 (M = 69.98, SD = 5.56) were randomized to one of three 12-week training programs: aerobic training (AET) = 26, gross motor abilities (GMA) = 27, and cognition (COG) = 25. Before and after the training program, the participants underwent physical fitness tests, and cognitive evaluations involving a computerized cognitive dual task. The AET consisted of high- and low-intensity aerobic training, the GMA of full-body exercises focusing on agility, balance, coordination, and stretching, and the COG of tablet-based exercises focusing on executive functions. RESULTS: Repeated-measures analysis of variance on reaction time data revealed a group × time interaction (F(2,75) = 11.91, p < .01) with COG having the greatest improvement, followed by a significant improvement in the GMA group. Secondary analysis revealed the COG to also improve the intraindividual variability in reaction time (F(1,24) = 8.62, p < .01), while the GMA improved the dual-task cost (F(1,26) = 12.74, p < .01). DISCUSSION: The results show that physical and cognitive training can help enhance dual-task performance by improving different aspects of the task, suggesting that different mechanisms are in play.


Assuntos
Análise e Desempenho de Tarefas , Idoso , Humanos , Cognição , Exercício Físico , Terapia por Exercício/métodos
13.
Front Aging Neurosci ; 14: 710958, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36408116

RESUMO

Cognitive-motor dual-tasking is a complex activity that predicts falls risk and cognitive impairment in older adults. Cognitive and physical training can both lead to improvements in dual-tasking; however, less is known about what mechanisms underlie these changes. To investigate this, 33 healthy older adults were randomized to one of three training arms: Executive function (EF; n = 10), Aerobic Exercise (AE; n = 10), Gross Motor Abilities (GMA; n = 13) over 12 weeks (1 h, 3×/week). Single and dual-task performance (gait speed, m/s; cognitive accuracy, %) was evaluated before and after training, using the 2-back as concurrent cognitive load. Training arms were designed to improve cognitive and motor functioning, through different mechanisms (i.e., executive functioning - EF, cardiorespiratory fitness - CRF, and energy cost of walking - ECW). Compared to baseline, we observed few changes in dual-task gait speed following training (small effect). However, dual-task cognitive accuracy improved significantly, becoming facilitated by walking (large effect). There were no differences in the magnitude of improvements across training arms. We also found that older adults with lower cognitive ability (i.e., MoCA score < 26; n = 14) improved more on the dual-task cognitive accuracy following training, compared to older adults with higher cognitive ability (i.e., MoCA ≥26; n = 18). Taken together, the results suggest that regardless of the type of intervention, training appears to strengthen cognitive efficiency during dual-tasking, particularly for older adults with lower baseline cognitive status. These gains appear to occur via different mechanisms depending on the form of intervention. Implications of this research are paramount, as we demonstrate multiple routes for improving cognitive-motor dual-tasking in older adults, which may help reduce risk of cognitive impairment.

14.
Int J Sports Physiol Perform ; 16(8): 1103­1110, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33789247

RESUMO

PURPOSE: To investigate the relationship between physical fitness and repeated high-intensity effort (RHIE) ability in elite rugby union players, depending on playing position. METHOD: Thirty-nine players underwent a fitness testing battery composed of a body composition assessment, upper-body strength (1-repetition maximum bench press and 1-repetition maximum bench row), lower-body strength (6-repetition maximum back squat), and power (countermovement jump, countermovement jump with arms, and 20-m sprint), as well as aerobic fitness (Bronco test) and RHIE tests over a 1-week period. Pearson linear correlations were used to quantify relationships between fitness tests and the RHIE performance outcomes (total sprint time [TST] and percentage decrement [%D]). Thereafter, a stepwise multiple regression model was used to verify the influence of physical fitness measures on RHIE ability. RESULTS: TST was strongly to very strongly associated to body fat (BF, r = .82, P < .01), the 20-m sprint (r = .86, P < .01), countermovement jump (r = -.72, P < .01), and Bronco test (r = .90, P < .01). These fitness outcomes were related to %D, with moderate to strong associations (.82 > ∣r∣ > .54, P < .01). By playing position, similar associations were observed in forwards, but RHIE ability was only related to the 20-m sprint in backs (r = .53, P < .05). The RHIE performance model equations were TST = 13.69 + 0.01 × BF + 0.08 × Bronco + 10.20 × 20 m and %D = -14.34 + 0.11 × BF +0.18 × Bronco - 9.92 × 20 m. These models explain 88.8% and 68.2% of the variance, respectively. CONCLUSION: Body composition, lower-body power, and aerobic fitness were highly related with RHIE ability. However, backs expressed a different profile than forwards, suggesting that further research with larger sample sizes is needed to better understand the fitness determinants of backs' RHIE ability.


Assuntos
Exercício Físico , Rugby , Humanos , Aptidão Física
15.
Int J Sports Physiol Perform ; 16(7): 993-1000, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33668014

RESUMO

PURPOSE: To assess the effects of a short-term taper on the ability to perform repeated high-intensity efforts, depending on players' fatigue level following an intensive training block. METHOD: After a 3-day off-season camp, 13 players followed the same 3-week preseason training block followed by a 7-day exponential taper. Performance was assessed by a repeated high-intensity effort test before and after the taper. Total sprint time, percentage of decrement, and the number of sprints equal to or higher than 90% of the best sprint were retained for analysis. Players were a posteriori classified in normal training or acute fatigue groups based on their readiness to perform prior to the taper, assessed through the magnitude of difference in psychological (Profile of Mood State Questionnaire), cardiovascular (submaximal constant-duration cycling), and neuromuscular (countermovement jump) tests between the preintensive and postintensive training blocks. RESULTS: Training load declined by 55% (9%) during the taper (P = .001, g = -2.54). The overall group showed a small improvement in total sprint time (-3.40% [3.90%], P = .04, g = -0.39) following the taper. Relative changes tended to be higher in the acute fatigue compared with the normal training group (-5.07% [4.52%] vs -1.45% [1.88%], respectively; P = .08; d = 1.01). No taper-induced improvement was observed in percentage of decrement or number of sprints equal to or higher than 90% of the best sprint. CONCLUSION: A 7-day taper consisting of 55% training load reduction improved repeated high-intensity effort performance in young elite rugby union players. Pretaper level of fatigue seems to be a key determinant in the taper supercompensation process, as acutely fatigued players at the end of the intensive training block tended to benefit more from the taper.


Assuntos
Desempenho Atlético , Futebol Americano , Fadiga , Humanos
16.
Physiol Behav ; 242: 113621, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34648819

RESUMO

AIM: The aim of the current study was to assess whether executive function and prefrontal oxygenation are dependent on fitness level and age in older adults. METHODS: Twenty-four healthy males aged between 55 and 69 years old were recruited for this study. They were stratified by age, leading to the creation of two groups: 55-60 years old and 61-69 years old. A median split based on CRF created higher- and lower-fit categories of participants. Cerebral oxygenation was assessed using functional near-infrared spectroscopy (fNIRS) during a computerized Stroop task. Accuracy (% of correct responses) and reaction times (ms) were used as behavioural indicators of cognitive performances. Changes in oxygenated (∆[HbO2]) and deoxygenated (∆[HHb]) hemoglobin were measured to capture neural changes. Repeated measures ANOVAs (CRF × Age × Stroop conditions) were performed to test the null hypothesis of an absence of interaction between CRF, Age and executive performance. RESULTS: We also found an interaction between CRF and age on reaction times (p = .001), in which higher fitness levels were related to faster reaction times in the 61-69 year olds but not in the 55-60 year olds. Regarding ΔHHb, the ANOVA revealed a main effect of CRF in the right PFC (p = .04), in which higher-fit participants had a greater Δ[HHb] than the lower-fit (d = 1.5). We also found fitness by age interaction for Δ[HHb] in the right PFC (p = .04). CONCLUSION: Our results support the positive association of CRF on cerebral oxygenation and Stroop performance in healthy older males. They indicated that high-fit individuals performed better in the 61-69 year olds group, but not in the 55-60 years old group. We also observed a greater PFC oxygenation change (as measured by Δ[HHb]) in the high-fit individuals.


Assuntos
Aptidão Cardiorrespiratória , Idoso , Função Executiva , Humanos , Masculino , Pessoa de Meia-Idade , Oxiemoglobinas/metabolismo , Córtex Pré-Frontal/metabolismo , Teste de Stroop
17.
Eur J Sport Sci ; 21(3): 300-311, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32172680

RESUMO

Purpose: To assess the effects of a taper strategy on neuromuscular and metabolic fitness in team sport athletes, through a systematic review and meta-analysis. Method: To be included in this meta-analysis, studies had to involve competitive team sport athletes and a tapering intervention providing details about the procedures used to decrease the training load, as well as competition or field-based criterion performance and all necessary data to calculate effect sizes. Four databases were searched according to these criteria, which led to the identification of 895 potential studies and the subsequent inclusion of 14 articles. Independent variables were training intensity, volume and frequency, as well as the pattern of taper and its duration. The dependent variable was performance obtained in various neuromuscular and metabolic tests. Results: There was limited evidence of a moderate taper-induced improvement in repeated sprint ability (Standardized Mean Difference (SMD) (95%IC;I2) = 0.41 (0.26-0.55;0%)) and moderate evidence of a moderate increase in maximal power (SMD (95%IC;I2) = 0.44 (0.32-0.56;15%)), change of direction speed (SMD (95%IC;I2) = 0.38 (0.15-0.60;28%)) and maximal oxygen uptake (SMD (95%IC;I2) = 0.76 (0.43-1.09;37%)). Conclusion: Tapering is an effective training strategy to improve maximal power, maximal oxygen uptake, repeated sprint ability and change of direction speed in team sports. However, the literature lacks studies using various tapering strategies to compare their effectiveness and make evidence-based recommendations. Future original studies should focus on this major issue.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Condicionamento Físico Humano/métodos , Esportes de Equipe , Adaptação Fisiológica/fisiologia , Adaptação Psicológica , Intervalos de Confiança , Humanos , Movimento/fisiologia , Força Muscular/fisiologia , Consumo de Oxigênio/fisiologia , Condicionamento Físico Humano/estatística & dados numéricos , Corrida/fisiologia , Fatores de Tempo
18.
Front Psychol ; 12: 742184, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803824

RESUMO

Associations between cardiorespiratory fitness and brain health in healthy older adults have been reported using a variety of cardiorespiratory fitness estimates (CRFe). Using commonly used methods to determine CRF, we assessed the relationship between CRFe and executive function performance. Healthy older adults (n = 60, mean age 68 years, 77% women), underwent three CRF tests: a Maximal Graded Exercise Test performed on a cycle ergometer, the Rockport Fitness Walking Test, and a Non-Exercise Prediction Equation. Executive function was assessed by a computerized cognitive assessment using an N-Back task (updating cost) and a Stroop task (interference cost, global and local switch cost). Multiple hierarchical regression analyses were conducted to assess the relationship between different CRFe and executive function performance. Regardless of age and education, cardiorespiratory fitness estimated from the Maximal Graded Exercise Test and the Rockport Fitness Walking Test was significantly associated with the global switch cost. All CRFe were associated with the interference cost. No association was observed between CRFe and local switching costs or the updating costs. In the present study, not all subcomponents of executive function were related to CRFe. Interestingly, the executive functions that were associated with CRFe are those that are known to be the most affected by aging.

19.
Exp Gerontol ; 149: 111331, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33774144

RESUMO

OBJECTIVES: Mobility is a complex but crucial clinical outcome in older adults. Past observational studies have highlighted that cardiorespiratory fitness (CRF), energy cost of walking (ECW), and cognitive switching abilities are associated with mobility performance, making these key determinants of mobility intervention targets to enhance mobility in older adults. The objective of this study was to compare, in the same design, the impact of three training methods - each known to improve either CRF, ECW, or cognitive switching abilities - on mobility in healthy older adults. METHODS: Seventy-eight participants (69.28 ± 4.85yo) were randomly assigned to one of three twelve-week interventions: Aerobic Exercise (AE; n = 26), Gross Motor Abilities (GMA; n = 27), or Cognitive (COG; n = 25) training. Each intervention was designed to improve one of the three key determinants of mobility (CRF, ECW, and cognitive switching). Primary outcomes (usual gait speed, and TUG performance) and the three mobility determinants were measured before and after the intervention. RESULTS: Repeated-measures ANOVAs showed a time effect for TUG performance (F(1,75) = 14.92, p < .001): all groups equally improved after the intervention (ΔTUGpost-pre, in seconds, with 95% CI: AE = -0.44 [-0.81 to -0.08]; GMA = -0.60 [-1.10 to -0.10]; COG = -0.33 [-0.71 to 0.05]). No significant between group differences were observed. CRF was improved in the AE group only (Hedges' G = 0.27, small effect), ECW and cognitive switching improved the most in the GMA (Hedges' G = -0.78, moderate effect) and COG groups (Hedges' G = -1.93, large effect) respectively. Smaller improvements in ECW were observed following AE and COG trainings (Hedges' G: AE = -0.39, COG = -0.36, both small effects) as well as in cognitive switching following AE and GMA training (Hedges' G: AE = -0.42, GMA = -0.21, both small effects). DISCUSSION: This study provides further support to the notion that multiple interventional approaches (aerobic, gross motor exercise, or cognitive training) can be employed to improve functional mobility in older adults, giving them, and professionals, more options to promote healthy ageing.


Assuntos
Cognição , Exercício Físico , Idoso , Terapia por Exercício , Humanos , Caminhada , Velocidade de Caminhada
20.
J Gerontol B Psychol Sci Soc Sci ; 76(8): 1533-1541, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-32803232

RESUMO

BACKGROUND: Studies report benefits of physical exercise and cognitive training to enhance cognition in older adults. However, most studies did not compare these interventions to appropriate active controls. Moreover, physical exercise and cognitive training seem to involve different mechanisms of brain plasticity, suggesting a potential synergistic effect on cognition. OBJECTIVE: This study investigated the synergistic effect of cognitive training and aerobic/resistance physical exercise on dual-task performance in older adults. Intervention effects were compared to active controls for both the cognitive and the exercise domain. METHOD: Eighty-seven older adults completed one of 4 different combinations of interventions, in which computer lessons was active control for cognitive training and stretching/toning exercise control for aerobic/resistance training: (a) cognitive dual-task training and aerobic/resistance training (COG+/AER+), (b) computer lessons and aerobic/resistance training (COG-/AER+), (c) cognitive dual-task training and stretching/toning exercises (COG+/AER-), and (d) computer lessons and stretching/toning exercises (COG-/AER-). The primary outcome was performance in an untrained transfer dual task. Stepwise backward removal regression analyses were used to predict pre- versus post-test changes in groups that have completed the dual-task training, aerobic/resistance or both interventions. RESULTS: Participation in AER+ did not predict improvement in any dual-task outcomes. Participation in COG+ predicted reduction in dual-task cost and participation in COG+/AER+ predicted reduction in task-set cost. DISCUSSION: Results suggest that the combination of cognitive and physical training protocols exerted a synergistic effect on task-set cost which reflects the cost of maintaining multiple response alternatives, whereas cognitive training specifically improved dual-task cost, which reflects the ability of synchronizing concurrent tasks.


Assuntos
Atenção/fisiologia , Remediação Cognitiva , Função Executiva/fisiologia , Terapia por Exercício , Desempenho Psicomotor/fisiologia , Transferência de Experiência/fisiologia , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Exercício Físico/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Treinamento Resistido
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