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1.
Arq Bras Cardiol ; 117(2): 309-316, 2021 08.
Artigo em Inglês, Português | MEDLINE | ID: mdl-34495225

RESUMO

BACKGROUND: Although maximal and submaximal walking are recommended for patients with peripheral artery disease (PAD), performing these exercises may induce different physiological responses. OBJECTIVES: To compare the acute effects of maximal and submaximal walking on post-exercise cardiovascular function, regulation, and associated pathophysiological processes in patients with symptomatic PAD. METHODS: Thirty male patients underwent 2 sessions: maximal walking (Gardner's protocol) and submaximal walking (15 bouts of 2 minutes of walking separated by 2 minutes of upright rest). In each session, blood pressure (BP), heart rate (HR), cardiac autonomic modulation (HR variability), forearm and calf blood flows (BF), vasodilatory capacity (reactive hyperemia), nitric oxide (NO), oxidative stress (lipid peroxidation), and inflammation (four markers) were measured pre- and post-walking. ANOVAs were employed, and p < 0.05 was considered significant. RESULTS: Systolic and mean BP decreased after the submaximal session, but they increased after the maximal session (interactions, p < 0.001 for both). Diastolic BP did not change after the submaximal session (p > 0.05), and it increased after maximal walking (interaction, p < 0.001). HR, sympathovagal balance, and BF increased similarly after both sessions (moment, p < 0.001, p = 0.04, and p < 0.001, respectively), while vasodilatory capacity, NO, and oxidative stress remained unchanged (p > 0.05). Vascular and intercellular adhesion molecules increased similarly after both maximal and submaximal walking sessions (moment, p = 0.001). CONCLUSIONS: In patients with symptomatic PAD, submaximal, but not maximal walking reduced post-exercise BP, while maximal walking maintained elevated cardiac overload during the recovery period. On the other hand, maximal and submaximal walking sessions similarly increased post-exercise HR, cardiac sympathovagal balance, and inflammation, while they did not change post-exercise NO bioavailability and oxidative stress.


Assuntos
Doença Arterial Periférica , Caminhada , Pressão Sanguínea , Teste de Esforço , Frequência Cardíaca , Humanos , Claudicação Intermitente , Masculino
2.
Sports (Basel) ; 9(7)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34357937

RESUMO

The current study examined the acute effects of a bout of resistance training on cricket bowling-specific motor performance. Eight sub-elite, resistance-untrained, adolescent male fast bowlers (age 15 ± 1.7 years; height 1.8 ± 0.1 m; weight 67.9 ± 7.9 kg) completed a bout of upper and lower body resistance exercises. Indirect markers of muscle damage (creatine kinase [CK] and delayed onset of muscle soreness [DOMS]), anaerobic performance (15-m sprint and vertical jump), and cricket-specific motor performance (ball speed, run-up time, and accuracy) were measured prior to and 24 (T24) and 48 (T48) hours following the resistance training bout. The resistance training bout significantly increased CK (~350%; effect size [ES] = 1.89-2.24), DOMS (~240%; ES = 1.46-3.77) and 15-m sprint times (~4.0%; ES = 1.33-1.47), whilst significantly reducing vertical jump height (~7.0%; ES = 0.76-0.96) for up to 48 h. The ball speed (~3.0%; ES = 0.50-0.61) and bowling accuracy (~79%; ES = 0.39-0.70) were significantly reduced, whilst run-up time was significantly increased (~3.5%; ES = 0.36-0.50) for up to 24 h. These findings demonstrate that a bout of resistance training evokes exercise-induced muscle damage amongst sub-elite, adolescent male cricketers, which impairs anaerobic performance and bowling-specific motor performance measures. Cricket coaches should be cautious of incorporating bowling sessions within 24-h following a bout of resistance training for sub-elite adolescent fast bowlers, particularly for those commencing a resistance training program.

3.
Sports Med ; 51(10): 2181-2207, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34097298

RESUMO

BACKGROUND: The relationship between exercise-induced muscle damage (EIMD) indicators and acute training loads (TL) is yet to be reviewed extensively in semi-elite and elite athlete populations. OBJECTIVES: The objectives of this systematic review and meta-analysis were threefold: (1) to evaluate studies of EIMD following the initial period of the preseason in semi-elite and elite athletes: (2) to examine acute physiological and performance responses across two periods of the season with similar TL; and (3) to examine acute physiological and performance responses to acute changes in TL during the season. METHODS: The CINAHL, PubMed, Scopus, SPORTDiscus and Web of Science databases were systematically searched for studies that investigated: (1) semi-elite or elite athletes in team or individual sports following a periodised training programme; and (2) measured acute responses to training. Studies were excluded if: (1) conducted in animals; (2) non-English language; or (3) a conference abstract, review or case report. The Kmet Quality Scoring of Quantitative Studies tool was used for study appraisal. SYNTHESIS METHODS: Data were quantitatively analysed by generating forest plots to report test statistics for statistical significance and inter-trial heterogeneity. RESULTS: Of the included studies (n = 32), athletes experienced greater creatine kinase (CK) concentrations (Z = 4.99, p < 0.00001, I2 = 74%), inflammatory factors and other indirect measures of muscle damage in the initial phase of the preseason period compared to the off-season; there were no changes in CK (Z = 1.43, p = 0.15, I2 = 74%) across two time points of similar TL; and there were concurrent increases in CK with increases in TL (Z = 4.26, p < 0.0001, I2 = 36%) and vice versa (Z = 4.33, p < 0.0001, I2 = 79%).The qualitative analysis identified that the response of inflammatory factors and other indirect measures of muscle damage to changes in load were inconclusive. LIMITATIONS: This review included varying age, sex, sports and competition levels. The group level meta-analysis failed to identify within-athlete or position-specific differences across time. CONCLUSION: Blood biomarkers of EIMD may not differ across periods of similar TL, however can be considered a sensitive monitoring tool for assessing responses following acute TL changes in semi-elite and elite athletes.

4.
Arq Bras Cardiol ; 116(5): 898-905, 2021 05.
Artigo em Inglês, Português | MEDLINE | ID: mdl-34008811

RESUMO

BACKGROUND: Walking training (WT) improves walking capacity and reduces clinic blood pressure (BP) in patients with peripheral artery disease (PAD), but its effects on ambulatory BP remains unknown. OBJECTIVE: To investigate the effect of 12 weeks of WT on ambulatory BP and its variability in patients with PAD. METHODS: Thirty-five male patients with PAD and claudication symptoms were randomly allocated into two groups: control (n = 16, 30 min of stretching) and WT (n = 19, 15 bouts of 2 min of walking at the heart rate of leg pain threshold interspersed by 2 min of upright rest). Before and after 12 weeks, 24-hour ambulatory BP was assessed. Ambulatory BP variability indices assessed at both time points included the 24-hour standard deviation (SD24), the awake and asleep weighted standard deviation (SDdn), and the 24-hour average real variability (ARV24). Data were analyzed by mixed two-way ANOVAs, considering P<0.05 as significant. RESULTS: After 12 weeks, neither group had significant changes in 24-hour, awake and sleep BPs. The WT decreased systolic and mean BP variabilities (Systolic BP - 13.3±2.8 vs 11.8±2.3, 12.1±2.84 vs 10.7±2.5 and 9.4±2.3 vs 8.8±2.2 mmHg); Mean BP - 11.0±1.7 vs 10.4±1.9, 10.1±1.6 vs 9.1±1.7 and 8.0.±1.7 vs 7.2±1.5 mmHg) for SD24, SDdn and ARV24, respectively). Neither group had significant changes in diastolic BP variabilities after 12 weeks. CONCLUSIONS: The WT does not change ambulatory BP levels but decreases ambulatory BP variability in patients with PAD. This improvement may have a favorable impact on the cardiovascular risk of patients with symptomatic PAD. (Arq Bras Cardiol. 2021; 116(5):898-905).


Assuntos
Hipertensão , Caminhada , Pressão Sanguínea , Monitorização Ambulatorial da Pressão Arterial , Frequência Cardíaca , Humanos , Claudicação Intermitente/terapia , Masculino
5.
Eur J Vasc Endovasc Surg ; 61(6): 954-963, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33875324

RESUMO

OBJECTIVE: This study examined the impact of submaximal walking training (WT) on local and systemic nitric oxide (NO) bioavailability, inflammation, and oxidative stress in patients with intermittent claudication (IC). METHODS: The study employed a randomised, controlled, parallel group design and was performed in a single centre. Thirty-two men with IC were randomly allocated to two groups: WT (n = 16, two sessions/week, 15 cycles of two minutes walking at an intensity corresponding to the heart rate obtained at the pain threshold interspersed by two minutes of upright rest) and control (CO, n = 16, two sessions/week, 30 minutes of stretching). NO bioavailability (blood NO and muscle nitric oxide synthase [eNOS]), redox homeostasis (catalase [CAT], superoxide dismutase [SOD], lipid peroxidation [LPO] measured in blood and muscle), and inflammation (interleukin-6 [IL-6], C-reactive protein [CRP], tumour necrosis factor α [TNF-α], intercellular adhesion molecules [ICAM], vascular adhesion molecules [VCAM] measured in blood and muscle) were assessed at baseline and after 12 weeks. RESULTS: WT statistically significantly increased blood NO, muscle eNOS, blood SOD and CAT, and muscle SOD and abolished the increase in circulating and muscle LPO observed in the CO group. WT decreased blood CRP, ICAM, and VCAM and muscle IL-6 and CRP and eliminated the increase in blood TNF-α and muscle TNF-α, ICAM and VCAM observed in the CO group. CONCLUSION: WT at an intensity of pain threshold improved NO bioavailability and decreased systemic and local oxidative stress and inflammation in patients with IC. The proposed WT protocol provides physiological adaptations that may contribute to cardiovascular health in these patients.


Assuntos
Exercício Físico/fisiologia , Inflamação , Claudicação Intermitente , Músculo Esquelético/metabolismo , Estresse Oxidativo , Caminhada/fisiologia , Adaptação Fisiológica/fisiologia , Proteína C-Reativa/análise , Teste de Esforço/métodos , Fatores de Risco de Doenças Cardíacas , Humanos , Claudicação Intermitente/sangue , Claudicação Intermitente/fisiopatologia , Claudicação Intermitente/terapia , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/análise , Avaliação de Resultados em Cuidados de Saúde , Superóxido Dismutase/análise , Molécula 1 de Adesão de Célula Vascular/análise
6.
Physiother Theory Pract ; : 1-20, 2021 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-33870831

RESUMO

Handgrip strength (HGS) is a functional test that has been directly associated with lung function in some healthy populations; however, inconsistent findings have been reported for populations with chronic diseases. The aim of this study was to identify the relationship between HGS and lung function in both healthy and unhealthy adults. A systematic search was conducted using six databases from their earliest inception to February 29, 2020. Two authors reviewed and assessed methodological quality of eligible studies using the Crowe Critical Appraisal Tool (CCAT). Twenty-five studies met the inclusion criteria with 8 and 17 studies examining healthy and unhealthy populations, respectively. Reported average methodological quality of all included studies using the CCAT was 38-85% with most rated as Good to Excellent. Despite the use of heterogeneous equipment and protocols during HGS and lung function assessments, significant positive and moderate correlations and/or regression coefficients were reported for healthy populations consistently. Conversely, the reported relationships between HGS and lung function for unhealthy counterparts were variable. Handgrip strength was significantly associated with lung function in most healthy adults. Future robust studies are needed to confirm the suitability of HGS to assess lung function for healthy and unhealthy adults.

7.
Ann Vasc Surg ; 2021 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33905859

RESUMO

AIM: A simple objective test is required to identify people with impaired physical aspects of health-related quality of life (QOL) due to intermittent claudication. This study assessed the relationship of QOL, function and physical activity to the need to stop during a six-minute walking test (6MWT) amongst people with intermittent claudication. METHOD: This was a prospective case-control study conducted at two centers in Australia. 173 participants with a history of intermittent claudication and peripheral artery disease diagnosed by ankle brachial pressure index <0.9, completed two 6MWTs one week apart. QOL was assessed with the short form (SF)-36. Physical activity was assessed by an accelerometer to record step count, stepping time and energy expenditure over 7 days. Physical performance was assessed by the Short Physical Performance Battery (SPPB) test. The associations of the need to stop at least once during the 6MWT with QOL, function and activity were assessed using Mann Whitney U test and analysis of covariates. RESULTS: Participants that had to stop at least once during the two 6MWTs (46; 26.6%) had significantly lower scores for three of the domains (physical functioning, role-physical and bodily pain) and the physical component summary (PCS) measure of the SF-36 compared to those who did not need to stop (n = 127; 73.4%). After adjusting for the risk factor co-variates (diabetes, hypertension and ankle brachial pressure index) which were significantly unequally distributed, needing to stop during the 6MWTs was significantly associated with a lower PCS score (adjusted mean 36.5, standard error 0.8 vs. 30.5, standard error 1.3; F = 14.0; P < 0.001; partial eta squared 0.077). Participants that had to stop at least once during the two 6MWTs had significantly lower 7-day step count, time stepping and energy expenditure, but not total SPPB score, compared to those who did not need to stop. CONCLUSIONS: Needing to stop during a 6MWT identified participants with intermittent claudication with poorer QOL and less physical activity compared to those that do not need to stop.

8.
J Sports Sci ; 39(8): 936-943, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33234010

RESUMO

We aimed to assess the cardiovascular responses and locomotory demands of male referees during diverse elite, international, basketball matches, and to investigate the influence of moderating factors (competition sex, level and stage) on these demands. Cardiovascular and locomotory responses were monitored in 123 elite, male referees while officiating 283 basketball sessions (preparation until match end), during group and playoff stages, of women's and men's FIBA Continental and World Cups at senior and youth level. The total and average session distance and velocity were ~4740 m, 19.0 m·min -1 and 2 km·h -1. Referees experienced an average relative HR of 60-65% maximum HR with ~85% of each session spent within the very light to moderate HR categories. The average session relative HR was significantly greater for men compared to women competition, during senior compared to youth sessions, and for the group compared to the playoff stage sessions. Mean distance covered was significantly greater during senior and men compared with youth and women sessions. Elite, international male basketball referees experienced moderate cardiovascular load accompanied with intermittent locomotor activities during international sessions when accounting for all occupational activities. International competitions are more demanding for referees based upon competition sex, level and stage.


Assuntos
Basquetebol/fisiologia , Comportamento Competitivo/fisiologia , Frequência Cardíaca , Corrida/fisiologia , Adulto , Antropometria , Composição Corporal , Estudos Transversais , Feminino , Humanos , Masculino
10.
Eur J Sport Sci ; : 1-11, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33070741

RESUMO

The root mean square of successive differences (RMSSD) of R-R intervals, the most robust vagal modulation parameter of heart rate variability (HRV), has been proposed as a marker of global health and training adaptations. The weekly averaging of RMSSD and its natural logarithm (LnRMSSD) has been adopted to enhance detection of training-induced adaptations. We assessed measures of aerobic fitness, body composition, objective physical activity (PA), and daily LnRMSSD recordings during different conditions, such as supine rest, seated rest, standing and walking at 5 km/h, over a week in 34 healthy young individuals of both sexes (age: 22 ± 4 yr; body fatness: 20 ± 8%; estimated VO2max: 40 ± 8 mL·kg-1·min-1). The day-to-day reliability and agreement among LnRMSSD averages over 5, 4, 3, 2 and a single-day value per condition were assessed, while correlations between LnRMSSD, aerobic fitness, body composition, and PA were also examined. Poor to good day-to-day reliability, and moderate to excellent agreement were observed for LnRMSSD recordings for diverse conditions with a minimum of two daily recordings in the supine condition, and three in the other conditions achieving excellent agreement for weekly HRV assessment. Several correlations between LnRMSSD, aerobic fitness, body composition, and PA were revealed, with stronger observed associations during walking. Utilisation of weekly HRV (average of 2-3 daily recordings), as described in the current study, may provide practitioners with a tool to assess weekly vagal modulations for health and performance purposes. Walking HRV recordings may be a practical alternative to other conditions for the investigation of cardiac autonomic function.

11.
Res Q Exerc Sport ; : 1-8, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32840455

RESUMO

Identification of the exercise volume and intensity of basketball referees, across competitive match types based on competition sex and level, would assist in developing appropriate training regimes. Purpose: The aims of this study were to quantify and compare the exercise volume and intensity encountered by semiprofessional basketball referees during different match types across a competitive season. Method: Sixteen referees participated and were monitored for absolute and relative PlayerLoad (PL) using microsensors during 25 semiprofessional matches (12 men's, 13 women's, 17 regular season, eight playoff). Comparisons between match types (men's vs. women's; regular season vs. playoff) were examined via independent t-tests or Mann-Whitney U tests, and repeated measures ANOVA with the magnitude of differences calculated via effect size. Results: Referees experienced an absolute PL of ~365 arbitrary units (AU) per match that was similar for men's, women's, regular season, and playoff matches during a competitive season. Relative PL was significantly greater (5.35 ± 0.82 vs. 4.26 ± 0.59 AU.min-1, p < .001, effect size = 1.57) during women's matches with a greater proportion of each quarter and match spent within PL band 2 compared to men's matches (11.6 ± 2.2 vs. 8.8 ± 1.4%, p < .001, effect size = 1.53), likely due to a reduced number of referees officiating. Minimal differences existed between the regular season and playoff matches for absolute PL, relative PL, and proportion of quarter/match time within PL bands. Conclusion: The current study confirmed that referees experienced considerable exercise volume and intensity per match during a competitive season with these influenced primarily by referee configuration. The current results provide crucial information to develop effective training regimes for referees during a competitive season.

12.
Artigo em Inglês | MEDLINE | ID: mdl-32751559

RESUMO

The aim of the present study was to examine the differences in game-related statistics between national and foreign female basketball players in the Women's EuroLeague, according to playing positions and team ability. The official box-scores of 112 games from the 2016-2017 season of the Women's EuroLeague (FIBA) were examined. Players were categorised based upon country of nationality versus competition (i.e., foreign or national), playing positions (i.e., Guards, Forwards, Centers), and team ability (i.e., four groups using a cluster of k-means analysis according to the winning percentage of each team during the competition). A structural coefficient (SC) above |0.30| was used to identify the variables that best differentiated the national and foreign players. Results showed that foreign players had a better performance according to team ability and playing position for most of the performance indicators, with higher values for minutes played, percentage of successful 2-point field-goals, percentage of successful free-throws, and percentage of assists. Moreover, foreign players performed better in variables associated with offensive situations, while national players were prevailing with indicators associated with defensive actions. These results have highlighted the unique contributions of foreign and national players, based upon playing position and team ability, to team success in the Euroleague. This information will assist the recruitment process of national and foreign athletes for coaches to develop successful elite female basketball teams.


Assuntos
Desempenho Atlético , Basquetebol , Atletas , Feminino , Humanos , Internacionalidade
13.
Artigo em Inglês | MEDLINE | ID: mdl-32784740

RESUMO

The FIBA Basketball World Cup is one of the most prominent sporting competitions for men's basketball, with coaches interested in key performance indicators (KPIs) that give a better understanding of basketball competitions. The aims of the study were to (1) examine the relationship between match KPIs and outcome in elite men's basketball; and (2) identify the most suitable analysis (multiple linear regression (MLR) vs. quantile regression (QR)) to model this relationship during the men's basketball tournament. A total of 184 performance records from 92 games were selected and analyzed via MLR and QR, using 10th, 25th, 50th, 75th and 90th quantiles. Several offensive (Paint Score, Mid-Range Score, Three-Point Score, Offensive Rebounds and Turnovers) and defensive (Defensive Rebounds, Steals and Personal Fouls) KPIs were associated with match outcome. The QR model identified additional KPIs that influenced match outcome than the MLR model, with these being Mid-Range Score at the 10th quantile and Offensive Rebounds at the 90th quantile. In terms of contextual variables, the quality of opponent had no impact on match outcome across the entire range of quantiles. Our results highlight QR modelling as a potentially superior tool for performance analysts and coaches to design and monitor technical-tactical plans during match-play. Our study has identified the KPIs contributing to match success at the 2019 FIBA Basketball World Cup with QR modelling assisting with a more detailed performance analysis, to support coaches with the optimization of training and match-play styles.


Assuntos
Desempenho Atlético , Basquetebol , Futebol , Logro , Adulto , Humanos , Masculino , Análise Multivariada
14.
Front Psychol ; 11: 1654, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32849010

RESUMO

The purpose of this study was to examine performance advantages associated with batting stance, in the form of left- vs. right-handed dominant stance, and orthodox vs. reverse stance, of talented junior cricket batters within age-restricted competitions. Data were sourced from the national male younger age competition (YAC; Under-17; n = 237) and older age competition (OAC; Under-19; n = 302), as well as female YAC (Under-15; n = 234) and OAC (Under-18; n = 260) over a 4-year period. Left-hand dominant (LHD) batters were consistently overrepresented in the male YAC (Right: 69.2%; Left: 30.8%) and OAC (Right: 68.2%; Left: 31.8%) compared with the expected general population distribution. Male LHD batters exhibited a significantly (p < 0.05) higher batting aggregate (YAC: 116.82 ± 84.75 vs. 137.84 ± 89.74; OAC: 117.07 ± 89.00 vs. 146.28 ± 95.99), scored more runs (YAC: 19.65 ± 12.32 vs. 23.96 ± 14.71; OAC: 19.27 ± 12.61 vs. 23.98 ± 14.15), spent more time batting (YAC: 45.33 ± 25.89 min vs. 54.59 ± 28.62 min; OAC: 39.80 ± 21.79 min vs. 49.33 ± 27.41 min), and scored more boundary-4s per game (YAC: 1.83 ± 1.40 vs. 2.44 ± 1.87; OAC: 1.76 ± 1.32 vs. 2.19 ± 1.83), across both YAC and OAC groups with small effect sizes. No overrepresentation was present for either female group (YAC, Right: 88.5%/Left: 11.5%; OAC, Right: 90.0%/Left: 10.0%). Female LHD batters exhibited significantly higher batting aggregate (68.97 ± 53.17 vs. 102.96 ± 73.48), batting average (13.24 ± 10.88 vs. 17.75 ± 12.28), and spent more time batting per game (25.52 ± 15.08 vs. 37.75 ± 26.76 min), but only at the OAC level with small-moderate effects sizes. Finally, there were few performance advantages identified to batting with a reverse stance, with further work needed to clarify any potential biomechanical benefits. Team selection practices may exploit the left-handed advantage by over-selecting talented left-handed junior cricketers. Practical implications for coaches include creating practice environments that negate the negative frequency-dependent selection, such as providing more practice opportunities for their players against left-handed opponents.

15.
J Cardiovasc Nurs ; 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32427794

RESUMO

OBJECTIVE: The aim of this study was to assess the effects of a single bout of maximal walking on blood and muscle nitric oxide (NO) bioavailability, oxidative stress, and inflammation in symptomatic peripheral artery disease (PAD) patients. METHODS: A total of 35 men with symptomatic PAD performed a graded maximal exercise test on a treadmill (3.2 km/h, 2% increase in grade every 2 minutes). Plasma samples and gastrocnemius muscle biopsies were collected preexercise and postexercise for assessment of NO bioavailability (plasma NO and muscle, endothelial NO synthase), oxidative stress and antioxidant function (lipid peroxidation [LPO], catalase [CAT], and superoxide dismutase), and inflammation (interleukin-6, C-reactive protein, tumor necrosis factor-α, intercellular adhesion molecules, and vascular adhesion molecules). The effects of the walking exercise were assessed using paired t tests or Wilcoxon tests. RESULTS: After maximal walking, plasma NO and LPO were unchanged (P > .05), plasma CAT decreased, and all blood inflammatory markers increased (all P ≤ .05). In the disease-affected skeletal muscle, endothelial NO synthase, CAT, LPO, and all inflammatory markers increased, whereas superoxide dismutase decreased (all P ≤ .05). CONCLUSION: In patients with symptomatic PAD, maximal exercise induces local and systemic impairments, which may play a key role in atherogenesis. Exercise strategies that avoid maximal effort may be important to reduce local and systemic damage and enhance clinical benefits.

16.
Eur J Appl Physiol ; 120(7): 1601-1607, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32424726

RESUMO

PURPOSE: The aim of the current study was to examine the impact of lower body compression garments (CG) on cardiac autonomic control of heart rate (HR) prior to, during and following submaximal exercise. METHODS: Thirty (15 males, 15 females) healthy, active adults undertook consecutive 10-min stages of supine rest, moderate-intensity upright cycling and supine recovery while wearing either normal clothing (CONTROL) or normal clothing plus CG tights in a randomised order. Heart rate (HR) and rating of perceived exertion (RPE) were assessed every minute while cardiovascular autonomic responses were assessed during the final 5 min of each stage via HR variability (HRV). The change in HR at 1-min (HRR1) and 2-min (HRR2) post-exercise and the time constant of HR recovery (HRtau) were assessed as indices of cardiac autonomic reactivation. Differences between variables were assessed via repeated measures ANOVA and corrected pairwise comparisons. RESULTS: Compared to rest, exercise resulted in a reduction of HRV that was similar for CONTROL and CG. A main effect for condition was identified for one non-linear, long-term HRV variable only with a significantly lower value (61.4 ± 47.8 vs. 67.1 ± 50.2 ms, p < 0.05) for CG compared to CONTROL. Cardiac autonomic reactivation (HRR1, 42.0 ± 16.8 vs. 45.5 ± 13.4 bpm; HRR2, 58.9 ± 10.5 vs. 58.9 ± 8.2 bpm; HRtau, 63.4 ± 22.3 vs. 65.1 ± 23.0 s, p > 0.05) was comparable for CONTROL and CG. CONCLUSION: Lower body CG failed to alter most cardiac autonomic responses during rest, moderate-intensity exercise or recovery. Mechanisms for potential ergogenic benefits of CG remain to be characterised.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Fenômenos Fisiológicos Cardiovasculares , Exercício Físico/fisiologia , Coração/fisiologia , Adulto , Teste de Esforço , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Adulto Jovem
18.
Eur J Vasc Endovasc Surg ; 59(6): 957-964, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32336621

RESUMO

OBJECTIVE: The aims of this study were firstly to assess the correlation between disease specific measures of quality of life (QOL) and physical performance and activity, and secondly to identify demographic, clinical, functional, and physical activity measures independently associated with QOL in people with intermittent claudication. METHODS: This was a cross sectional observational study of 198 people with intermittent claudication caused by peripheral artery disease who were recruited prospectively. QOL was assessed with the intermittent claudication questionnaire (ICQ) and the eight-theme peripheral artery disease quality of life questionnaire. Physical performance was assessed with the six minute walk test (6MWT) and short physical performance battery (SPPB), and an accelerometer was used to measure seven day step count. The associations between QOL scores and 6MWT distance, SPPB scores and seven day step count were examined using Spearman Rho's (ρ) correlation and multivariable linear regression. RESULTS: ICQ scores were significantly correlated with 6MWT distance (ρ = 0.472, p < .001), all four SPPB scores (balance ρ = 0.207, p = .003; gait speed ρ = 0.303, p < .001; chair stand ρ = 0.167, p = .018; total ρ = 0.265, p < .001), and seven day step count (ρ = 0.254, p < .001). PADQOL social relationships and interactions (ρ = 0.343, p < .001) and symptoms and limitations in physical functioning (ρ = 0.355, p < .001) themes were correlated with 6MWT distance. The 6MWT distance was independently positively associated with ICQ and both PADQOL theme scores (ICQ: B 0.069, p < .001; PADQOL social relationships and interactions: B 0.077, p < .001; PADQOL symptoms and limitations in physical functioning: B 0.069, p < .001). CONCLUSION: Longer 6MWT distance independently predicted better physical and social aspects of QOL in people with intermittent claudication supporting its value as an outcome measure.


Assuntos
Claudicação Intermitente/diagnóstico , Medidas de Resultados Relatados pelo Paciente , Doença Arterial Periférica/complicações , Desempenho Físico Funcional , Qualidade de Vida , Idoso , Estudos Transversais , Feminino , Humanos , Claudicação Intermitente/etiologia , Claudicação Intermitente/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Teste de Caminhada
19.
PLoS One ; 15(3): e0229604, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32126074

RESUMO

The aim of the present study was twofold: (i) to identify contextual variables associated with the occurrence of long rallies while investigating time-related and technical parameters; and (ii) to identify performance differences between long rallies and the subsequent rally when accounting for match-context and the players' sex. The sample included 60 men's (n = 4,475 rallies) and 60 women's (n = 4,490 rallies) matches randomly selected from the 2015 World Badminton Super Series and World Championship (the final sample included long rallies that had an immediate next point played: n = 1,734 and n = 1,644 rallies for male and female players, respectively). The long rallies represented 19.4% (n = 867) and 16.5% (n = 822) of total rallies for male and female players, respectively. Long rallies were established using a two-step cluster model based on rally time and number of strokes for male (13-79s, 14-72 strokes) and female players (11-56s, 11-52 strokes). The variables collected were point outcome (when serving and receiving, winner, forced-error and unforced-error), number of strokes per rally, rally time, rest time, density, and time between strokes. The rallies were classified into different contexts (clusters) according to influencing factors with eight clusters for male players and three clusters for female players identified. Comparisons among clusters were conducted using Kruskal Wallis and one-way ANOVAs. Comparisons between long and immediate next points were conducted using the Wilcoxon tests for most variables and Crosstabs Command for point outcome and rallies (long and immediate next). Statistically significant differences were identified for both sexes among clusters only for time-related variables (i.e., rally time, rest time, density and time between strokes). In addition, a greater number of strokes, longer rally, rest time, and higher density were identified during long rallies compared with the immediate next rally for both men's and women's matches (p<0.05). The time between strokes during long rallies was significantly greater for male players during clusters 3, 5, 6, and 7 (p<0.05) and significantly lower for female players during all clusters (p<0.05). Significant relationships were identified between winning point outcome, and more unforced errors when serving during the immediate next rally (men's cluster 5 and women's cluster 2), and more winners when serving during the immediate next rally (men's cluster 6). The current study identified and characterised long rallies in elite men´s and women´s badminton matches highlighting the importance of sex and contextual factors on time-related and technical demands. Information obtained from these unique sequences of play (i.e., long and immediate next rallies) will assist coaches when modelling and simulating players' performances (i.e., physiologically and cognitively) during athlete preparation/competition.


Assuntos
Desempenho Atlético/fisiologia , Esportes com Raquete/fisiologia , Adulto , Desempenho Atlético/estatística & dados numéricos , Análise por Conglomerados , Feminino , Humanos , Masculino , Esportes com Raquete/estatística & dados numéricos , Caracteres Sexuais , Fatores de Tempo
20.
J Sports Med Phys Fitness ; 60(5): 779-785, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32141276

RESUMO

BACKGROUND: Asthma and obesity are becoming increasingly common among children. Such conditions are known to negatively affect both cardiac autonomic function and oxidative stress. We therefore investigated the heart rate variability (HRV) and oxidative (malondialdehyde, MDA) response to exercise within a high humidity environment (~65%) in obese and lightweight asthmatic children. METHODS: Forty-two children participated in this study and were categorized into four groups: obese asthmatic (OA, N.=10), obese non-asthmatic (ONA, N.=15), lightweight asthmatic (LA, N.=10), and lightweight non-asthmatic (LNA, N.=7). Time-domain and nonlinear indices of HRV were assessed at rest, during, and immediately after exercise. Further, saliva samples were collected immediately before and after exercise and analyzed for the determination of MDA. RESULTS: HRV significantly decreased during and after exercise compared to baseline (P<0.05) with short-term fractal scaling exponent (α1) for the LNA group significantly smaller than the OA group after exercise (P<0.05). In contrast, the long-term fractal scaling exponent (α2) was greater after exercise compared to baseline and during exercise for all groups (P<0.05). MDA significantly decreased after exercise compared to baseline (P<0.05). We also found significant correlations after exercise between salivary levels of MDA with HRV components (i.e., RMSSD, SD1, and α2) in asthmatic groups (all P<0.05). CONCLUSIONS: Our findings showed that exercise in high humidity environment does not significantly differentiate the autonomic response among children with various conditions (i.e., obese, asthmatic and healthy). However, a significant relationship was found between HRV and MDA in asthmatic children after exercise, highlighting the inter-relationship between oxidative stress markers and autonomic function in asthmatic children.


Assuntos
Asma/fisiopatologia , Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Umidade/efeitos adversos , Obesidade/fisiopatologia , Estresse Oxidativo/fisiologia , Asma/complicações , Sistema Nervoso Autônomo/fisiologia , Estudos de Casos e Controles , Criança , Teste de Esforço/métodos , Feminino , Humanos , Masculino , Obesidade/complicações , Saliva/metabolismo
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