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1.
Amino Acids ; 56(1): 4, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300362

RESUMO

This study investigated the effect of high-intensity interval exercise on total and individual amino acid concentrations in red blood cells (RBCs) and plasma. Seven males (31 ± 13 yr) provided venous blood samples at rest, immediately and 15 min and 30 min following an 8-min high-intensity exercise bout. The exercise bout was 16 × 15 s cycle efforts at 0.4N/kg of body mass and 90 rpm, interspersed with 15 s passive recovery. Total and individual amino acid concentrations of RBC and plasma and blood cell parameters were analysed. No significant differences for total amino acid concentrations between RBC and plasma were found. Individual amino acid analyses showed significant interaction effects for alanine and α-aminoadipic acid (P < 0.05), with plasma alanine significantly increased from baseline across the recovery period (P < 0.001). Blood fraction (group) effects showed greater concentrations of glycine, serine, asparagine, aspartic acid, glutamic acid, α-aminoadipic acid and ornithine in RBC, while greater concentrations of alanine, α-aminobutyric acid, valine, leucine, isoleucine, threonine, proline, phenylalanine, glutamine, tryptophan and cystine were found in plasma (P < 0.05). Comparable levels of histidine, lysine and tyrosine were observed between blood fractions. Significant differences in the variation of total amino acids in RBC were reported with higher variance at rest compared to following exercise (P = 0.01). Haemoglobin, pack cell volume and white blood cell count significantly increased immediately following exercise (P < 0.05) but returned to baseline after 15 min recovery. These results support the notion of individualised amino acid transportation roles for RBC and plasma during exercise.


Assuntos
Aminoácidos , Eritrócitos , Masculino , Humanos , Plasma , Alanina , Ácido Glutâmico
2.
J Sports Sci ; 41(6): 565-572, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37343951

RESUMO

This study investigated the impact of match location and travel modality on physical performance of an Australian A-League association football team. Match location comprised of a home vs away comparison; while travel modality compared home matches, road travel, short-flight travel, and long-flight travel. Both models accounted for match result, opposition quality and total distance covered. Physical performance was defined as average running intensity (m.min-1), low-speed activity (LSA), high-speed activity (HSA), very high-speed activity (VHSA), high-intensity efforts (HIE) and sprint efforts. Statistical significance was accepted at p < 0.05. Match location results demonstrated significantly greater average running intensity and LSA for away matches and significantly greater HSA for home matches. Travel modality results demonstrated significantly greater LSA for road travel compared to home matches and long-flight travel, while HSA was significantly greater for home matches and long-flight travel than for road travel. Additionally, home matches demonstrated significantly greater VHSA than road travel. Assessing the impact of travel modality on physical performance provides more contextual information than solely home vs away. Coaches may use this information to plan travel to mitigate detrimental effects on physical performance, particularly concerning road travel on matchdays.


Assuntos
Desempenho Atlético , Rugby , Humanos , Austrália , Sistemas de Informação Geográfica , Desempenho Físico Funcional
3.
J Sports Sci ; 41(24): 2161-2168, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38390955

RESUMO

This study aimed to establish injury incidence rates (IIRs) and burden within an Australian male professional football club (n = 73) and to investigate longitudinal trends across five consecutive seasons (2016/17-2020/21). There was an overall IIR of 9.18 injuries per 1000 hours (h) (95% CI [7.89, 10.47]). The IIR was approximately seven times greater (rate ratio (RR): 6.85; 95% CI [5.13, 9.19]; p < 0.01) in matches (31.29 injuries per 1000 h; 95% CI [25.25, 37.33]) compared to training (4.49 injuries per 1000 h; 95% CI [3.51, 5.47]). The overall injury burden was 254.1 days lost per 1000 h (95% CI [220.9, 292.3]). Compared with the reference 2016/17 season, there were significant increases in minimal (RR: 6.94; 95% CI [1.27, 128.73]) and mild injuries (RR: 3.76; 95% CI [1.21, 16.39]) in season 2017/18 and decreases in moderate (RR: 0.40; 95% CI [0.19, 0.80]) and contact injuries (RR: 0.35; 95% CI [0.12, 0.90]) in season 2019/2020. Time-loss injury is common and represents a major burden in Australian male professional football, with injuries more frequently sustained during matches. Injury prevention practices should specifically be directed towards muscle/tendon and ligament injuries of the lower limb, particularly anterior cruciate ligament, ankle sprain and hamstring strain injuries.


Assuntos
Traumatismos em Atletas , Traumatismos da Perna , Rugby , Lesões dos Tecidos Moles , Humanos , Masculino , Traumatismos em Atletas/epidemiologia , Austrália/epidemiologia , Incidência
4.
J Strength Cond Res ; 36(10): 2905-2911, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33394893

RESUMO

ABSTRACT: Milne, EC, Vickery, WM, Dascombe, BJ, and Borges, NR. Development of a twenty20 field-based simulation for cricket fast bowlers (FBS-T20). J Strength Cond Res 36(10): 2905-2911, 2022-This project assessed the validity and reliability of a novel Twenty20 cricket pace bowling simulation (FBS-T20) that could be used to facilitate match-specific testing and training outside of match play. Six recreational pace bowlers completed 3 identical sessions of the FBS-T20. The FBS-T20 consisted of 4 bowling and 16 fielding overs. During the bowling overs, a bowling accuracy test and bowling approach speed were measured, whereas during the fielding overs, 10-m sprint performance was assessed. Distance covered, heart rate (HR), and rating of perceived exertion (RPE) were also collected throughout the FBS-T20. Validity was determined through comparison with previously reported Twenty20 pace bowling match demands, and intersession reliabilities were assessed. Distances covered in speed zones were valid ( p > 0.05) with the exception of significantly lower jog values in the FBS-T20 (957-1,279 vs. 2,195 m; p = 0.04-<0.001). The maximal HR was found to be valid, but the mean HR was significantly higher than previously published data (147-151 bpm vs. 133 bpm; p = 0.014-0.003). Distances covered demonstrated high levels of reliability, with increasing reliability found after additional sessions (coefficient of variation [CV]% = 3.8-14.4). The HR (CV% = 4.8-6.3) and session RPE (CV% = 10.8) demonstrated moderate reliability, whereas approach speed, 10-m sprint, and bowling skills test results possessed low levels of reliability. The FBS-T20 is a practically viable testing and training tool that is valid and reliable for distances covered at high speeds. One full familiarization session is recommended for optimal reliability.


Assuntos
Esportes , Fenômenos Biomecânicos/fisiologia , Frequência Cardíaca , Humanos , Reprodutibilidade dos Testes , Esportes/fisiologia
5.
J Aging Phys Act ; 29(3): 544-551, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33291066

RESUMO

Aging is anecdotally associated with a prolonged recovery from resistance training, though current literature remains equivocal. This brief review considers the effects of resistance training on indirect markers of muscle damage and recovery (i.e., muscle soreness, blood markers, and muscle strength) in older males. With no date restrictions, four databases were searched for articles relating to aging, muscle damage, and recovery. Data from 11 studies were extracted for review. Of these, four reported worse symptoms in older compared with younger populations, while two have observed the opposite, and the remaining studies (n = 6) proposed no differences between age groups. It appears that resistance training can be practiced in older populations without concern for impaired recovery. To improve current knowledge, researchers are urged to utilize more ecologically valid muscle-damaging bouts and investigate the mechanisms which underpin the recovery of muscle soreness and strength after exercise in older populations.


Assuntos
Músculo Esquelético , Treinamento de Força , Idoso , Envelhecimento , Suplementos Nutricionais , Humanos , Masculino , Força Muscular , Mialgia
6.
Int J Sports Physiol Perform ; 15(5): 759-762, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32000141

RESUMO

PURPOSE: Due to age-related changes in the psychobiological state of masters athletes, this brief report aimed to compare training load responses using heart rate (HR) and ratings of perceived exertion (RPE) during standardized training sessions between masters and young cyclists. METHODS: Masters (n = 10; 55.6 [5.0] y) and young (n = 8; 25.9 [3.0] y) cyclists performed separate endurance and high-intensity interval training sessions. Endurance intensity was set at 95% of ventilatory threshold 2 for 1 hour. High-intensity interval training consisted of 6 × 30-second intervals at 175% peak power output with 4.5-minute rest between intervals. HR was monitored continuously and RPE collected at standardized time periods during each session. Banister training impulse and summated-HR-zones training loads were also calculated. RESULTS: Despite a significantly lower mean HR in masters cyclists during endurance (P = .04; d = 1.06 [±0.8], moderate) and high-intensity interval training (P = .01; d = 1.34 [±0.8], large), no significant differences were noted (P > .05) when responses were determined relative to maximum HR or converted to training impulse and summated-HR-zone loads. Furthermore, no interaction or between-group differences were evident for RPE across either session (P > .05). CONCLUSIONS: HR and RPE values were comparable between masters and young cyclists when relative HR responses and HR training load models are used. This finding suggests HR and RPE methods used to monitor or prescribe training load can be used interchangeably between masters and young athletes irrespective of chronological age.


Assuntos
Envelhecimento/fisiologia , Ciclismo/fisiologia , Frequência Cardíaca , Treinamento Intervalado de Alta Intensidade/métodos , Percepção/fisiologia , Esforço Físico/fisiologia , Adulto , Humanos , Pessoa de Meia-Idade
7.
PLoS One ; 14(10): e0223381, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31581276

RESUMO

Concentrations of free amino acids and [K+] in human sweat can be many times higher than in plasma. Conversely, [Na+] and [Cl-] in sweat are hypotonic to plasma. It was hypothesised that the amino acids and K+ were directly or indirectly associated with the resorption of Na+ and Cl- in the sweat duct. The implication would be that, as resources of these components became limiting during prolonged exercise then the capacity to resorb [Na+] and [Cl-] would diminish, resulting in progressively higher levels in sweat. If this were the case, then [Na+] and [Cl-] in sweat would have inverse relationships with [K+] and the amino acids during exercise. Forearm sweat was collected from 11 recreational athletes at regular intervals during a prolonged period of cycling exercise after 15, 25, 35, 45, 55 and 65 minutes. The subjects also provided passive sweat samples via 15 minutes of thermal stimulation. The sweat samples were analysed for concentrations of amino acids, Na+, Cl-, K+, Mg2+ and Ca2+. The exercise sweat had a total amino acid concentration of 6.4 ± 1.2mM after 15 minutes which was lower than the passive sweat concentration at 11.6 ± 0.8mM (p<0.05) and showed an altered array of electrolytes, indicating that exercise stimulated a change in sweat composition. During the exercise period, [Na+] in sweat increased from 23.3 ± 3.0mM to 34.6 ± 2.4mM (p<0.01) over 65 minutes whilst the total concentrations of amino acids in sweat decreased from 6.4 ± 1.2mM to 3.6 ± 0.5mM. [Na+] showed significant negative correlations with the concentrations of total amino acids (r = -0.97, p<0.05), K+ (r = -0.93, p<0.05) and Ca2+ (r = -0.83, p<0.05) in sweat. The results supported the hypothesis that amino acids and K+, as well as Ca2+, were associated with resorption of Na+ and Cl-.


Assuntos
Aminoácidos/análise , Cloretos/análise , Eletrólitos/análise , Exercício Físico , Potássio/análise , Sódio/análise , Suor/química , Sudorese , Adolescente , Adulto , Aminoácidos/metabolismo , Cloretos/metabolismo , Eletrólitos/metabolismo , Feminino , Humanos , Masculino , Potássio/metabolismo , Sódio/metabolismo , Suor/metabolismo , Adulto Jovem
8.
J Sport Health Sci ; 7(2): 176-182, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30356430

RESUMO

PURPOSE: The aims of this study were to: (1) provide a comprehensive physiological profile of simulated basketball activity and (2) identify temporal changes in player responses in controlled settings. METHODS: State-level male basketball players (n = 10) completed 4 × 10 min simulated quarters of basketball activity using a reliable and valid court-based test. A range of physiological (ratings of perceived exertion, blood lactate concentration ([BLa-]), blood glucose concentration ([BGlu]), heart rate (HR), and hydration) and physical (performance and fatigue indicators for sprint, circuit, and jump activity) measures were collected across testing. RESULTS: Significantly reduced [BLa-] (6.19 ± 2.30 vs. 4.57 ± 2.33 mmol/L; p = 0.016) and [BGlu] (6.91 ± 1.57 vs. 5.25 ± 0.81 mmol/L; p = 0.009) were evident in the second half. A mean HR of 180.1 ± 5.7 beats/min (90.8% ± 4.0% HRmax) was observed, with a significant increase in vigorous activity (77%-95% HRmax) (11.31 ± 6.91 vs. 13.50 ± 6.75 min; p = 0.024) and moderate decrease in near-maximal activity (>95% HRmax) (7.24 ± 7.45 vs. 5.01 ± 7.20 min) in the second half. Small increases in performance times accompanied by a significantly lower circuit decrement (11.67% ± 5.55% vs. 7.30% ± 2.16%; p = 0.032) were apparent in the second half. CONCLUSION: These data indicate basketball activity imposes higher physiological demands than previously thought and temporal changes in responses might be due to adapted pacing strategies as well as fatigue-mediated mechanisms.

9.
Exp Aging Res ; 44(4): 338-349, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29843564

RESUMO

BACKGROUND: The purpose of this study was to compare physical performance, perceptual and haematological markers of recovery in well-trained masters and young cyclists across 48 h following a bout of repeated high-intensity interval exercise. METHODS: Nine masters (mean ± SD; age = 55.6 ± 5.0 years) and eight young (age = 25.9 ± 3.0 years) cyclists performed a high-intensity interval exercise session consisting of 6 × 30 s intervals at 175% peak power output with 4.5 min rest between efforts. Maximal voluntary contraction (MVC), 10 s sprint (10SST), 30-min time trial (30TT) performance, creatine kinase concentration (CK) and perceptual measures of motivation, total recovery, fatigue and muscle soreness were collected at baseline and at standardised time points across the 48 h recovery period. RESULTS: No significant group-time interactions were observed for performance of MVC, 10SST, 30TT and CK (P > 0.05). A significant reduction in 10SST peak power was found in both masters (P = 0.002) and young (P = 0.003) cyclists at 1 h post exercise, however, both groups physically recovered at similar rates. Neither group showed significant (P > 0.05) or practically meaningful increases in CK (%∆ < 10%). A significant age-related difference was found for perceptual fatigue (P = 0.01) and analysis of effect size (ES) showed that perceptual recovery was delayed with masters cyclists reporting lower motivation (ES ±90%CI = 0.69 ± 0.77, moderate), greater fatigue (ES = 0.75 ± 0.93, moderate) and muscle soreness (ES = 0.61 ± 0.70, moderate) after 48 h of recovery. CONCLUSION: The delay in perceived recovery may have negative effects on long-term participation to systematic training.


Assuntos
Envelhecimento/fisiologia , Envelhecimento/psicologia , Exercício Físico/psicologia , Adulto , Desempenho Atlético , Ciclismo , Biomarcadores , Creatina Quinase/sangue , Exercício Físico/fisiologia , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Motivação , Fadiga Muscular/fisiologia , Mialgia/fisiopatologia , Desempenho Psicomotor/fisiologia , Recuperação de Função Fisiológica , Adulto Jovem
10.
J Sports Sci ; 36(8): 852-860, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28636479

RESUMO

This study quantified lower-limb strength decrements and assessed the relationships between strength decrements and performance fatigue during simulated basketball. Ten adolescent, male basketball players completed a circuit-based, basketball simulation. Sprint and jump performance were assessed during each circuit, with knee flexion and extension peak concentric torques measured at baseline, half-time, and full-time. Decrement scores were calculated for all measures. Mean knee flexor strength decrement was significantly (P < 0.05) related to sprint fatigue in the first half (R = 0.65), with dominant knee flexor strength (R = 0.67) and dominant flexor:extensor strength ratio (R = 0.77) decrement significantly (P < 0.05) associated with sprint decrement across the entire game. Mean knee extensor strength (R = 0.71), dominant knee flexor strength (R = 0.80), non-dominant knee flexor strength (R = 0.75), mean knee flexor strength (R = 0.81), non-dominant flexor:extensor strength ratio (R = 0.71), and mean flexor:extensor strength ratio (R = 0.70) decrement measures significantly (P < 0.05) influenced jump fatigue during the entire game. Lower-limb strength decrements may exert an important influence on performance fatigue during basketball activity in adolescent, male players. Consequently, training plans should aim to mitigate lower-limb fatigue to optimise sprint and jump performance during game-play.


Assuntos
Basquetebol/fisiologia , Joelho/fisiologia , Fadiga Muscular/fisiologia , Força Muscular/fisiologia , Adolescente , Estudos Transversais , Humanos , Extremidade Inferior/fisiologia , Masculino , Análise e Desempenho de Tarefas
11.
Clin Auton Res ; 27(2): 83-90, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28154947

RESUMO

PURPOSE: This study aimed at examining the autonomic cardiovascular modulation in well-trained masters and young cyclists following high-intensity interval training (HIT). METHODS: Nine masters (age 55.6 ± 5.0 years) and eight young cyclists (age 25.9 ± 3.0 years) completed a HIT protocol of 6 x 30 sec at 175% of peak power output, with 4.5-min' rest between efforts. Immediately following HIT, heart rate and R-R intervals were monitored for 30-min during passive supine recovery. Autonomic modulation was examined by i) heart rate recovery in the first 60-sec of recovery (HRR60); ii) the time constant of the 30-min heart rate recovery curve (HRRτ); iii) the time course of the root mean square for successive 30-sec R-R interval (RMSSD30); and iv) time and frequency domain analyses of subsequent 5-min R-R interval segments. RESULTS: No significant between-group differences were observed for HRR60 (P = 0.096) or HRRτ (P = 0.617). However, a significant interaction effect was found for RMSSD30 (P = 0.021), with the master cyclists showing higher RMSSD30 values following HIT. Similar results were observed in the time and frequency domain analyses with significant interaction effects found for the natural logarithm of the RMSSD (P = 0.008), normalised low-frequency power (P = 0.016) and natural logarithm of high-frequency power (P = 0.012). CONCLUSION: Following high-intensity interval training, master cyclists demonstrated greater post-exercise parasympathetic reactivation compared to young cyclists, indicating that physical training at older ages has significant effects on autonomic function.


Assuntos
Ciclismo/fisiologia , Frequência Cardíaca/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Recuperação de Função Fisiológica/fisiologia , Adulto , Fatores Etários , Sistema Nervoso Autônomo/fisiologia , Fenômenos Fisiológicos Cardiovasculares , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Int J Sports Physiol Perform ; 12(2): 168-174, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27197090

RESUMO

PURPOSE: The influence of various factors on training-load (TL) responses in basketball has received limited attention. This study aimed to examine the temporal changes and influence of cumulative training dose on TL responses and interrelationships during basketball activity. METHODS: Ten state-level Australian male junior basketball players completed 4 × 10-min standardized bouts of simulated basketball activity using a circuit-based protocol. Internal TL was quantified using the session rating of perceived exertion (sRPE), summated heart-rate zones (SHRZ), Banister training impulse (TRIMP), and Lucia TRIMP models. External TL was assessed via measurement of mean sprint and circuit speeds. Temporal TL comparisons were performed between 10-min bouts, while Pearson correlation analyses were conducted across cumulative training doses (0-10, 0-20, 0-30, and 0-40 min). RESULTS: sRPE TL increased (P < .05) after the first 10-min bout of basketball activity. sRPE TL was only significantly related to Lucia TRIMP (r = .66-.69; P < .05) across 0-10 and 0-20 min. Similarly, mean sprint and circuit speed were significantly correlated across 0-20 min (r = .67; P < .05). In contrast, SHRZ and Banister TRIMP were significantly related across all training doses (r = .84-.89; P < .05). CONCLUSIONS: Limited convergence exists between common TL approaches across basketball training doses lasting beyond 20 min. Thus, the interchangeability of commonly used internal and external TL approaches appears dose-dependent during basketball activity, with various psychophysiological mediators likely underpinning temporal changes.


Assuntos
Basquetebol/fisiologia , Condicionamento Físico Humano/métodos , Adolescente , Basquetebol/psicologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Percepção , Esforço Físico/fisiologia , Fatores de Tempo
13.
Int J Sport Nutr Exerc Metab ; 27(1): 76-82, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27284754

RESUMO

Following exercise-induced muscle damage (EIMD), masters athletes take longer to recover than younger athletes. The purpose of this study was to determine the effect of higher than recommended postexercise protein feedings on the recovery of knee extensor peak isometric torque (PIT), perceptions of recovery, and cycling time trial (TT) performance following EIMD in masters triathletes. Eight masters triathletes (52 ± 2 y, V̇O2max, 51.8 ± 4.2 ml•kg-1•min-1) completed two trials separated by seven days in a randomized, doubleblind, crossover study. Trials consisted of morning PIT testing and a 30-min downhill run followed by an eight-hour recovery. During recovery, a moderate (MPI; 0.3 g•kg-1•bolus-1) or high (0.6 g•kg-1•bolus-1) protein intake (HPI) was consumed in three bolus feedings at two hour intervals commencing immediately postexercise. PIT testing and a 7 kJ•kg-1 cycling TT were completed postintervention. Perceptions of recovery were assessed pre- and postexercise. The HPI did not significantly improve recovery compared with MPI (p > .05). However, comparison of within-treatment change shows the HPI provided a moderate beneficial effect (d = 0.66), attenuating the loss of afternoon PIT (-3.6%, d = 0.09) compared with the MPI (-8.6%, d = 0.24). The HPI provided a large beneficial effect (d = 0.83), reducing perceived fatigue over the eight-hour recovery (d = 1.25) compared with the MPI (d = 0.22). Despite these effects, cycling performance was unchanged (HPI = 2395 ± 297 s vs. MPI = 2369 ± 278 s; d = 0.09). In conclusion, doubling the recommended postexercise protein intake did not significantly improve recovery in masters athletes; however, HPI provided moderate to large beneficial effects on recovery that may be meaningful following EIMD.


Assuntos
Desempenho Atlético , Proteínas na Dieta/administração & dosagem , Fadiga , Recomendações Nutricionais , Corrida , Fenômenos Fisiológicos da Nutrição Esportiva , Atletas , Ciclismo , Índice de Massa Corporal , Estudos Cross-Over , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Fadiga Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Mioglobina/sangue , Consumo de Oxigênio , Torque
14.
Int J Sports Physiol Perform ; 12(2): 260-263, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27140952

RESUMO

PURPOSE: Declines in high-intensity activity during game play (in-game approach) and performance tests measured pre- and postgame (across-game approach) have been used to assess player fatigue in basketball. However, a direct comparison of these approaches is not available. Consequently, this study examined the commonality between in- and across-game jump fatigue during simulated basketball game play. METHODS: Australian, state-level, junior male basketball players (n = 10; 16.6 ± 1.1 y, 182.4 ± 4.3 cm, 68.3 ± 10.2 kg) completed 4 × 10-min standardized quarters of simulated basketball game play. In-game jump height during game play was measured using video analysis, while across-game jump height was determined pre-, mid-, and postgame play using an in-ground force platform. Jump height was determined using the flight-time method, with jump decrement calculated for each approach across the first half, second half, and entire game. RESULTS: A greater jump decrement was apparent for the in-game approach than for the across-game approach in the first half (37.1% ± 11.6% vs 1.7% ± 6.2%; P = .005; d = 3.81, large), while nonsignificant, large differences were evident between approaches in the second half (d = 1.14) and entire game (d = 1.83). Nonsignificant associations were evident between in-game and across-game jump decrement, with shared variances of 3-26%. CONCLUSIONS: Large differences and a low commonality were observed between in- and across-game jump fatigue during basketball game play, suggesting that these approaches measure different constructs. Based on our findings, it is not recommended that basketball coaches use these approaches interchangeably to monitor player fatigue across the season.


Assuntos
Desempenho Atlético/fisiologia , Basquetebol/fisiologia , Fadiga Muscular/fisiologia , Adolescente , Humanos , Modelos Lineares , Masculino , Exercício Pliométrico , Estudos de Tempo e Movimento
15.
J Strength Cond Res ; 30(8): 2212-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27457915

RESUMO

Borges, NR and Driller, MW. Wearable lactate threshold predicting device is valid and reliable in runners. J Strength Cond Res 30(8): 2212-2218, 2016-A commercially available device claiming to be the world's first wearable lactate threshold predicting device (WLT), using near-infrared LED technology, has entered the market. The aim of this study was to determine the levels of agreement between the WLT-derived lactate threshold workload and traditional methods of lactate threshold (LT) calculation and the interdevice and intradevice reliability of the WLT. Fourteen (7 male, 7 female; mean ± SD; age: 18-45 years, height: 169 ± 9 cm, mass: 67 ± 13 kg, V[Combining Dot Above]O2max: 53 ± 9 ml·kg·min) subjects ranging from recreationally active to highly trained athletes completed an incremental exercise test to exhaustion on a treadmill. Blood lactate samples were taken at the end of each 3-minute stage during the test to determine lactate threshold using 5 traditional methods from blood lactate analysis which were then compared against the WLT predicted value. In a subset of the population (n = 12), repeat trials were performed to determine both inter-reliability and intrareliability of the WLT device. Intraclass correlation coefficient (ICC) found high to very high agreement between the WLT and traditional methods (ICC > 0.80), with TEMs and mean differences ranging between 3.9-10.2% and 1.3-9.4%. Both interdevice and intradevice reliability resulted in highly reproducible and comparable results (CV < 1.2%, TEM <0.2 km·h, ICC > 0.97). This study suggests that the WLT is a practical, reliable, and noninvasive tool for use in predicting LT in runners.


Assuntos
Limiar Anaeróbio , Ácido Láctico/sangue , Corrida/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação , Adolescente , Adulto , Biomarcadores/sangue , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
16.
Med Sci Sports Exerc ; 48(8): 1613-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27433963

RESUMO

PURPOSE: The objective of this study is to compare the integrated muscle protein synthesis (MPS) rates of masters and younger triathletes over three consecutive days of intense endurance training. Recovery of cycling performance, after muscle-damaging running, was also compared between groups. METHODS: Five masters (age, 53 ± 2 yr; V˙O2max, 55.7 ± 6.9 mL·kg·min) and six younger (age, 27 ± 2 yr; V˙O2max, 62.3 ± 1.5 mL·kg·min) trained triathletes volunteered for the study. Baseline skeletal muscle and saliva were initially sampled, after which a 150-mL bolus of deuterium oxide (70%) was consumed. Participants then completed a 30-min downhill run; three 20-km cycling time trials (TT) were completed 10, 24, and 48 h after the run. Saliva was collected each morning, and skeletal muscle was again sampled 72 h after the run; both were used for MPS analysis. Diet was controlled throughout the study. RESULTS: Over 3 d, masters triathletes showed a significantly lower myofibrillar fractional synthetic rate (1.49% ± 0.12%·d) compared with the younger (1.70% ± 0.09%·d) triathletes (P = 0.009, d = 1.98). There was also a trend for masters triathletes to produce a slower cycle TT (-3.0%, d = 0.46) than younger triathletes (-1.4%, d = 0.29) at 10 h postrun in comparison with the baseline performance. The between-group comparison of change was moderate (d = 0.51), suggesting slower acute recovery among masters triathletes. CONCLUSIONS: The present data show lower MPS rates in well-trained masters triathletes over 3 d of training, and this likely contributes to poorer muscle protein repair and remodeling. Furthermore, acute recovery of cycle TT performance tended to be poorer in the masters triathletes.


Assuntos
Fatores Etários , Ciclismo/fisiologia , Proteínas Musculares/biossíntese , Corrida/fisiologia , Adulto , Atletas , Teste de Esforço , Humanos , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Recuperação de Função Fisiológica
17.
J Aging Phys Act ; 24(1): 149-57, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25880787

RESUMO

Despite increasing participation rates in masters sport and extensive research examining age-related changes in performance, little is known about the effect of age on recovery kinetics in masters athletes. This narrative review focuses on the relationship between aging and sport participation, and the effect on both performance and recovery following an exercise bout. Current research suggests the effect of age on performance and recovery may be smaller than originally suggested and that increasing sedentary lifestyles appear to play a larger role in any observed decrements in performance and recovery in masters athletes. Currently, it appears that performance decrements are inevitable with age. However, performance capacities can be maintained through systematic physical training. Moreover, the limited current research suggests there may be an age effect on recovery kinetics following an exercise bout, although further research is required to understand the acute and chronic recovery processes in the masters athlete.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Fatores Etários , Idoso , Humanos , Cinética , Pessoa de Meia-Idade
18.
Int J Sports Physiol Perform ; 9(5): 851-6, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24434042

RESUMO

PURPOSE: To compare perceptual and physiological training-load responses during various basketball training modes. METHODS: Eight semiprofessional male basketball players (age 26.3 ± 6.7 y, height 188.1 ± 6.2 cm, body mass 92.0 ± 13.8 kg) were monitored across a 10-wk period in the preparatory phase of their training plan. Player session ratings of perceived exertion (sRPE) and heart-rate (HR) responses were gathered across base, specific, and tactical/game-play training modes. Pearson correlations were used to determine the relationships between the sRPE model and 2 HR-based models: the training impulse (TRIMP) and summated HR zones (SHRZ). One-way ANOVAs were used to compare training loads between training modes for each model. RESULTS: Stronger relationships between perceptual and physiological models were evident during base (sRPE-TRIMP r = .53, P < .05; sRPE-SHRZ r = .75, P < .05) and tactical/game-play conditioning (sRPE-TRIMP r = .60, P < .05; sRPE-SHRZ r = .63; P < .05) than during specific conditioning (sRPE-TRIMP r = .38, P < .05; sRPE-SHRZ r = .52; P < .05). Furthermore, the sRPE model detected greater increases (126-429 AU) in training load than the TRIMP (15-65 AU) and SHRZ models (27-170 AU) transitioning between training modes. CONCLUSIONS: While the training-load models were significantly correlated during each training mode, weaker relationships were observed during specific conditioning. Comparisons suggest that the HR-based models were less effective in detecting periodized increases in training load, particularly during court-based, intermittent, multidirectional drills. The practical benefits and sensitivity of the sRPE model support its use across different basketball training modes.


Assuntos
Desempenho Atlético , Basquetebol , Modelos Biológicos , Condicionamento Físico Humano , Adulto , Análise de Variância , Comportamento Competitivo , Frequência Cardíaca , Humanos , Masculino , Atividade Motora , Percepção , Fatores de Tempo , Adulto Jovem
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