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1.
Appl Physiol Nutr Metab ; 45(10): 1174-1177, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32544343

RESUMO

The long-term decay rate of serum ferritin post-iron infusion in athletic populations is currently unknown. Here, we modelled the decay rate of serum ferritin in female athletes after an intravenous iron infusion (n = 22). The post-infusion serum ferritin response and the rate of decay was highly variable between athletes; however, we demonstrate that follow-up blood testing at 1 (154 µg/L; 77-300 µg/L) and 6 months (107 µg/L; 54-208 µg/L) post-infusion is appropriate to observe treatment efficacy and effectiveness. Novelty Female athletes should have serum ferritin assessed at 1 and 6 months following an intravenous iron infusion to determine efficacy and effectiveness.


Assuntos
Anemia Ferropriva/sangue , Anemia Ferropriva/prevenção & controle , Atletas/estatística & dados numéricos , Ferritinas/sangue , Ferro/administração & dosagem , Adulto , Estudos de Coortes , Feminino , Humanos , Infusões Intravenosas , Estudos Retrospectivos , Adulto Jovem
2.
Int J Sport Nutr Exerc Metab ; 30(3): 191­196, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32217790

RESUMO

The authors compared the effectiveness of daily (DAY) versus alternate day (ALT) oral iron supplementation in athletes with suboptimal iron. Endurance-trained runners (nine males and 22 females), with serum ferritin (sFer) concentrations <50 µg/L, supplemented with oral iron either DAY or ALT for 8 weeks. Serum ferritin was measured at baseline and at fortnightly intervals. Hemoglobin mass (Hbmass) was measured pre- and postintervention in a participant subset (n = 10). Linear mixed-effects models were used to assess the effectiveness of the two strategies on sFer and Hbmass. There were no sFer treatment (p = .928) or interaction (p = .877) effects; however, sFer did increase (19.7 µg/L; p < .001) over the 8-week intervention in both groups. In addition, sFer was 21.2 µg/L higher (p < .001) in males than females. No Hbmass treatment (p = .146) or interaction (p = .249) effects existed; however, a significant effect for sex indicated that Hbmass was 140.85 g higher (p = .004) in males compared with females. Training load (p = .001) and dietary iron intake (p = .015) also affected Hbmass. Finally, there were six complaints of severe gastrointestinal side effects in DAY, but only one in ALT. In summary, both supplement strategies increased sFer in athletes with suboptimal iron status; however, the ALT approach was associated with lower incidence of gastrointestinal upset.

3.
Int J Sport Nutr Exerc Metab ; 30(3): 185­190, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32217791

RESUMO

The authors compared the effectiveness of two modes of daily iron supplementation in athletes with suboptimal iron stores: oral iron (PILL) versus transdermal iron (PATCH). Endurance-trained runners (nine males and 20 females), with serum ferritin concentrations <50 µg/L, supplemented with oral iron or iron patches for 8 weeks, in a parallel group study design. Serum ferritin was measured at baseline and fortnightly intervals. Hemoglobin mass and maximal oxygen consumption (V˙O2max) were measured preintervention and postintervention in PATCH. A linear mixed effects model was used to assess the effectiveness of each mode of supplementation on sFer. A repeated-measures analysis of variance was used to assess hemoglobin mass and V˙O2max outcomes in PATCH. There was a significant time effect (p < .001), sex effect (p = .013), and Time × Group interaction (p = .009) for sFer. At Week 6, PILL had significantly greater sFer compared with PATCH (15.27 µg/L greater in PILL; p = .019). Serum ferritin was 15.53 µg/L greater overall in males compared with females (p = .013). There were no significant differences in hemoglobin mass (p = .727) or V˙O2max (p = .929) preintervention to postintervention in PATCH. Finally, there were six complaints of severe gastrointestinal side effects in PILL and none in PATCH. Therefore, this study concluded that PILL effectively increased sFer in athletes with suboptimal iron stores, whereas PATCH showed no beneficial effects.

4.
J Sci Med Sport ; 23(6): 548-553, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32044233

RESUMO

OBJECTIVES: To investigate the behaviours of elite and developing athletes in obtaining medications and medication information, and to identify the role of pharmacists in athlete care. DESIGN: Cross-sectional survey. METHODS: An electronic, 39-item questionnaire was developed, piloted and distributed to elite and developing athletes aged 18 years and above at a state-based sporting institute. Quantitative data was analysed using descriptive statistics and free text comments were analysed using an inductive reasoning approach. RESULTS: A total of 98 responses were analysed. Ninety (n=90/98, 91.84%) participants obtained medications in the six months prior to survey completion. Pharmacies were the most common source of both prescription (n=67/69, 97.10%) and non-prescription medications (n=64/75, 85.33%). Forty-five (n=45/98, 45.92%) participants also attended pharmacies when they had a minor ailment. Sixty-two (n=62/98, 63.27%) participants 'sometimes' consulted pharmacists for medication information. Only 11 (n=11/98, 11.22%) knew, according to their sporting institute medication policy, that athletes were required to consult a medical practitioner before taking anti-inflammatory, pain-relieving or sleep-inducing medications. Forty (n=40/98, 40.82%) participants believed pharmacists could play a role in their medication management. CONCLUSIONS: Many elite and developing athletes visited pharmacies for medication supply and treatment of minor ailments. Doping regulatory agency websites were the most commonly used and trusted sources for medication information, although some athletes believed pharmacists could also contribute to their medication management. Future research should consider whether pharmacists are ready for a role in sports pharmacy.


Assuntos
Atletas/estatística & dados numéricos , Tomada de Decisões , Comportamento de Busca de Informação , Medicamentos sem Prescrição , Farmácias , Medicamentos sob Prescrição , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Inquéritos e Questionários , Adulto Jovem
5.
Med Sci Sports Exerc ; 51(10): 2147-2155, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31058762

RESUMO

PURPOSE: This study examined postexercise inflammatory, hepcidin, and iron absorption responses to endurance exercise performed in the morning versus the afternoon. METHODS: Sixteen endurance-trained runners (10 male, 6 female) with serum ferritin (sFer) < 50 µg·L completed a 90-min running protocol (65% vV˙O2max) in the morning (AM), or the afternoon (PM), in a crossover design. An iron-fortified fluid labeled with stable iron isotopes (Fe or Fe) was administered with a standardized meal 30 min following the exercise and control conditions during each trial, serving as a breakfast and dinner meal. Venous blood samples were collected before, immediately after, and 3 h after the exercise and control conditions to measure sFer, serum interleukin-6 (IL-6), and serum hepcidin-25. A final venous blood sample was collected 14 d after each trial to determine the erythrocyte iron incorporation, which was used to calculate iron absorption. Linear mixed-modeling was used to analyze the data. RESULTS: Overall, exercise significantly increased the concentrations of IL-6 (4.938 pg·mL; P = 0.006), and hepcidin-25 concentrations significantly increased 3 h after exercise by 0.380 nM (P < 0.001). During the PM trial, hepcidin concentrations exhibited diurnal tendency, increasing 0.55 nM at rest (P = 0.007), before further increasing 0.68 nM (P < 0.001) from prerun to 3 h postrun. Fractional iron absorption was significantly greater at breakfast after the AM run, compared with both the rested condition (0.778%; P = 0.020) and dinner in the AM run trial (0.672%; P = 0.011). CONCLUSIONS: Although exercise resulted in increased concentrations of IL-6 and hepcidin, iron was best absorbed in the morning after exercise, indicating there may be a transient mechanism during the acute postexercise window to promote iron absorption opposing the homeostatic regulation by serum hepcidin elevations.


Assuntos
Hepcidinas/sangue , Interleucina-6/sangue , Ferro/sangue , Resistência Física/fisiologia , Esportes/fisiologia , Absorção Fisiológica , Adulto , Estudos Cross-Over , Eritrócitos/metabolismo , Feminino , Ferritinas/sangue , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
6.
Int J Sport Nutr Exerc Metab ; 29(5): 518-525, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30859854

RESUMO

The authors aimed to update knowledge of the use of supplements among Australian athletes at a state-based sports institute. The authors conducted a cross-sectional survey using an online questionnaire to assess the influence of age, sports category, and scholarship category on supplement use. Of 94 completed questionnaires, 82 (87%) indicated supplements in the previous 12 months (mean = 4.9 ± 3.3). No significant difference in supplement usage rate was identified when considering age, scholarship category, or sport category. The most frequently used supplements were sports drinks (70%), caffeine (48%), protein powder (42%), and sports bars (42%). Recovery (63%), health maintenance (59%), and improved energy (50%) were the most frequently reported rationale to use supplements. Allied health professionals and credible online resources were the predominant sources of influence regarding use. However, athletes from lower scholarship categories were more likely to have social media, parents, and siblings influence usage, and age was inversely related to increased influence from parents, social media, physicians not associated with the institute, the Internet, and siblings. Older athletes and those on higher scholarships were more likely to source supplements from training facilities and sports nutrition staff outside of the institute or direct from a supplier, whereas those on lower scholarships tended to rely more on family and friends for their supplements. Findings from this study show a high prevalence of supplement use and are the first to show an influence of social media, particularly in younger athletes. Opportunities exist to optimize how athletes are informed regarding supplement use and organizational and supplement policy.


Assuntos
Atletas , Suplementos Nutricionais/estatística & dados numéricos , Adolescente , Adulto , Austrália , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Esportes , Inquéritos e Questionários , Adulto Jovem
7.
J Sports Sci ; 36(2): 162-170, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28282750

RESUMO

The aim of the present study was to investigate the influence of different types of tasks performed with or without an electronic device (tablet) on pre-sleep alertness, subsequent sleep quality and next-day athletic performance. Eight highly trained netball players attended a sleep laboratory for pre-sleep testing, polysomnographic sleep monitoring and next-day physical performance testing on 5 separate occasions (1 familiarisation and 4 experimental sessions). For 2 h prior to bedtime, athletes completed cognitively stimulating tasks (puzzles) or passive tasks (reading) with or without a tablet. Sleepiness tended to be greater after reading compared to completing puzzles without a tablet (d = 0.80), but not with a tablet. Melatonin concentration increased more so after reading compared to completing puzzles on a tablet (P = 0.02). There were no significant differences in sleep quality or quantity or next-day athletic performance between any of the conditions. These data suggest that using a tablet for 2 h prior to sleep does not negatively affect subsequent sleep or next-day performance in athletes.


Assuntos
Desempenho Atlético , Atenção , Microcomputadores/estatística & dados numéricos , Sono , Adolescente , Temperatura Corporal , Orelha Média/fisiologia , Feminino , Humanos , Hidrocortisona/metabolismo , Melatonina/metabolismo , Salvia/metabolismo , Análise e Desempenho de Tarefas
8.
Eur J Appl Physiol ; 114(5): 951-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24487960

RESUMO

PURPOSE: To assess the influence of a simulated altitude exposure (~2,900 m above sea level) for a 3 h recovery period following intense interval running on post-exercise inflammation, serum iron, ferritin, erythropoietin, and hepcidin response. METHODS: In a cross-over design, ten well-trained male endurance athletes completed two 8 × 3 min interval running sessions at 85 % of their maximal aerobic velocity on a motorized treadmill, before being randomly assigned to either a hypoxic (HYP: F IO2 ~0.1513) or a normoxic (NORM: F IO2 0.2093) 3 h recovery period. Venous blood was collected pre- and immediately post-exercise, and after 3 and 24 h of recovery. Blood was analyzed for interleukin-6, serum iron, ferritin, erythropoietin, and hepcidin. RESULTS: Interleukin-6 was significantly elevated (p < 0.01) immediately post-exercise compared to baseline (NORM: 1.08 ± 0.061 to 3.12 ± 1.80) (HYP: 1.32 ± 0.86 to 2.99 ± 2.02), but was not different between conditions. Hepcidin levels were significantly elevated (p < 0.01) at 3 h post-exercise for both conditions when compared to baseline (NORM: 3.25 ± 1.23 to 7.40 ± 4.00) (HYP: 3.24 ± 1.94 to 5.42 ± 3.20), but were significantly lower (p < 0.05) in the HYP trial compared to NORM. No significant differences existed between HYP and NORM for erythropoietin, serum iron, or ferritin. CONCLUSION: Simulated altitude exposure (~2,900 m) for 3 h following intense interval running attenuates the peak hepcidin levels recorded at 3 h post-exercise. Consequently, a hypoxic recovery after exercise may be useful for athletes with compromised iron status to potentially increase acute dietary iron absorption.


Assuntos
Altitude , Hepcidinas/sangue , Corrida/fisiologia , Adulto , Atletas , Estudos de Casos e Controles , Eritropoetina/sangue , Ferritinas/sangue , Humanos , Ferro/sangue , Masculino , Oxigênio/sangue
9.
Int J Sport Nutr Exerc Metab ; 24(3): 325-32, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24458099

RESUMO

This study investigated the influence of dehydration on urinary levels of pseudoephedrine (PSE) after prolonged repeated effort activity. Fourteen athletes performed a simulated team game circuit (STGC) outdoors over 120 min under three different hydration protocols: hydrated (HYD), dehydrated (DHY) and dehydrated + postexercise fluid bolus (BOL). In all trials, a 60 mg dose of PSE was administered 30 min before trial and at half time of the STGC. Urinary PSE levels were measured before drug administration and at 90 min postexercise. In addition, body mass (BM) changes and urinary specific gravity (USG), osmolality (OSM), creatinine (Cr), and pH values were recorded. No differences in PSE levels were found 90 min postexercise between conditions (HYD: 208.5 ± 116.5; DHY: 238.9 ± 93.5; BOL: 195.6 ± 107.3 µg · ml(-1)), although large variations were seen within and between participants across conditions (range: 33-475 µg · ml(-1): ICC r = .03-0.16, p > .05). There were no differences between conditions in USG, OSM, pH or PSE/Cr ratio. In conclusion, hydration status did not influence urinary PSE levels after prolonged repeated effort activity, with ~70% of samples greater than the WADA limit (>150 µg · ml(-1)), and ~30% under. Due to the unpredictability of urinary PSE values, athletes should avoid taking any medications containing PSE during competition.


Assuntos
Desidratação/urina , Exercício Físico/fisiologia , Futebol Americano/fisiologia , Esforço Físico , Pseudoefedrina/urina , Dopagem Esportivo , Humanos , Concentração de Íons de Hidrogênio , Masculino , Concentração Osmolar , Gravidade Específica
10.
Eur J Sport Sci ; 14(5): 410-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24093813

RESUMO

This study examined the effect of early evening high-intensity training on the sleep of elite male youth soccer players (n = 12) using wrist actigraphy. High-intensity training (TRAIN) nights were compared with a home environment (HOME) condition, created by averaging sleep variables on the night before and after TRAIN nights. Additionally, after TRAIN athletes alternately used cold water immersion (TRAIN+CWI) or none, to assess whether cold water immersion (CWI) had any impact on sleep quality and quantity. Ratings of perceived exertion, fatigue and recovery were recorded after training. Actigraphy sleep measures were bedtime, wake time, sleep duration, sleep onset latency, sleep efficiency and wake after sleep onset. Self-rated scores of sleepiness at bedtime and wake, plus overall sleep quality were also recorded. Only fatigue ratings were higher in TRAIN compared to TRAIN+CWI at bedtime, there were no other differences in training data. Both TRAIN and TRAIN+CWI conditions had significant later (07:45 ± 1:09 h p < 0.01 and 07:34 ± 1:20 h p = 0.01) wake times than HOME (06:44 ± 0:41 h). The TRAIN condition had a significantly higher (7 ± 2; p < 0.01) rating of sleepiness at bedtime compared to HOME (6 ± 1), but no further differences were found in any of the sleep (actigraphy and self-reported) measures. Across all conditions, time spent asleep was ∼7:30 (±0:52) h:min and sleep efficiency was ∼89% (±6.1). In conclusion, early evening high-intensity training had no impact on subsequent sleep quality and quantity, nor was there any effect on sleep after performing CWI post-training.


Assuntos
Exercício Físico/fisiologia , Esforço Físico/fisiologia , Sono , Futebol/fisiologia , Actigrafia , Adolescente , Adulto , Atletas , Temperatura Baixa , Fadiga , Frequência Cardíaca , Humanos , Imersão , Masculino , Projetos Piloto , Adulto Jovem
11.
Med Sci Sports Exerc ; 45(7): 1394-402, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23377833

RESUMO

PURPOSE: This study investigated the effect of cold water immersion after evening exercise on subsequent sleep quality and quantity in trained cyclists. METHODS: In the evenings (~1900 h) on three separate occasions, male cyclists (n = 11) underwent either no exercise (control, CON), exercise only (EX), or exercise followed by cold water immersion (CWI). EX comprised cycling for 15 min at 75% peak power, then a 15-min maximal time trial. After each condition, a full laboratory-based sleep study (polysomnography) was performed. Core and skin temperature, heart rate, salivary melatonin, ratings of perceived fatigue, and recovery were measured in each trial. RESULTS: No differences were observed between conditions for any whole night sleep measures, including total sleep time, sleep efficiency, sleep onset latency, rapid eye movement onset latency, wake after sleep onset, or proportion of the night spent in different sleep stages. Core temperature in EX and CWI trials was higher than CON, until it decreased below that of EX and CON until bedtime in CWI. After bedtime, core temperature was similar for all conditions throughout the night, except for a 90-min period where it was lower for CWI than EX and CON (3.5-4.5 h postexercise). Heart rates for EX and CWI were both significantly higher than CON postexercise until bedtime, whereas skin temperature after CWI was significantly lower than EX and CON, remaining lower than EX until 3 h postexercise. Melatonin levels and recovery ratings were similar between conditions. Fatigue ratings were significantly elevated after exercise in both CWI and EX conditions, with EX still being elevated compared with CON at bedtime. CONCLUSION: Whole night sleep architecture is not affected by evening exercise alone or when followed by CWI.


Assuntos
Banhos , Ciclismo/fisiologia , Temperatura Baixa , Sono/fisiologia , Adulto , Biomarcadores/metabolismo , Temperatura Corporal , Fadiga/etiologia , Frequência Cardíaca , Humanos , Masculino , Melatonina/metabolismo , Polissonografia , Fatores de Tempo
12.
Int J Sports Physiol Perform ; 8(3): 293-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23006673

RESUMO

PURPOSE: To assess the efficacy of a 1-off electrostimulation treatment as a recovery modality from acute team-sport exercise, directly comparing the benefits to contrast water therapy. METHODS: Ten moderately trained male athletes completed a simulated team-game circuit (STGC). At the conclusion of exercise, participants then completed a 30-min recovery modality of either electrostimulation therapy (EST), contrast water therapy (CWT), or a passive resting control condition (CON). Twenty-four hours later, participants were required to complete a modified STGC as a measure of next-day performance. Venous blood samples were collected preexercise and 3 and 24 h postexercise. Blood samples were analyzed for circulating levels of interleukin-6 (IL-6) and C-reactive protein (CRP). RESULTS: The EST trial resulted in significantly faster sprint times during the 24-h postrecovery than with CON (P < .05), with no significant differences recorded between EST and CWT or between CWT and CON (P > .05). There were no differences in IL-6 or CRP across all trials. Finally, the perception of recovery was significantly greater in the EST trial than in the CWT and CON (P < .05). CONCLUSIONS: These results suggest that a 1-off treatment with EST may be beneficial to perceptual recovery, which may enhance next-day performance.


Assuntos
Traumatismos em Atletas/reabilitação , Terapia por Estimulação Elétrica/métodos , Músculo Esquelético/lesões , Dor Musculoesquelética/reabilitação , Doença Aguda , Adolescente , Traumatismos em Atletas/fisiopatologia , Futebol Americano/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Músculo Esquelético/fisiopatologia , Dor Musculoesquelética/fisiopatologia , Esforço Físico/fisiologia , Recuperação de Função Fisiológica/fisiologia , Corrida/fisiologia , Futebol/fisiologia , Medicina Esportiva/métodos , Adulto Jovem
13.
Eur J Appl Physiol ; 113(2): 305-11, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22706550

RESUMO

To study the effect of post-exercise cold water immersion (CWI) on core temperature and melatonin responses, 10 male cyclists completed two evening (~1800 hours) cycling trials followed by a 15-min CWI (14 °C) or warm water immersion (WWI; 34 °C), and were then monitored for 90 min post-immersion. The exercise trial involved 15 min at 75 % peak power, followed by a 15 min time trial. Core (rectal) temperature was not different between the two conditions pre-exercise (~37.4 °C), post-exercise (~39 °C) or immediately post-immersion (~37.7 °C), but was significantly (p < 0.05) below pre-exercise levels at 60 and 90 min post-immersion in both conditions. Core temperature was significantly lower after CWI than WWI at 30 min (36.84 ± 0.24 vs. 37.42 ± 0.40 °C, p < 0.05) and 90 min (36.64 ± 0.24 vs. 36.95 ± 0.43 °C, p < 0.05) post-immersion. Salivary melatonin levels significantly increased (p < 0.05) from post-exercise (~5 pM) to 90 min post-immersion (~8.3 pM), but were not different between conditions. At 30 and 90 min post-immersion heart rate was significantly lower (~5-10 bpm, p < 0.01) after CWI than WWI. These results show that undertaking either CWI or WWI post-exercise in the evening lowers core temperature below baseline for at least 90 min; however, the magnitude of decrease is significantly greater following CWI. The usual evening increase in melatonin is unaffected by exercise or post-exercise water immersion undertaken between ~1800 and ~2000 hours.


Assuntos
Ciclismo/fisiologia , Temperatura Corporal/fisiologia , Temperatura Baixa , Imersão/fisiopatologia , Melatonina/metabolismo , Esforço Físico/fisiologia , Saliva/química , Adaptação Fisiológica/fisiologia , Adulto , Humanos , Masculino
14.
Clin J Sport Med ; 21(4): 330-6, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21562418

RESUMO

OBJECTIVE: The spinopelvic kinematics of sweep and scull have yet to be investigated, despite evidence suggesting that sweep rowing may be provocative for low back pain (LBP). The aim of this study was to determine whether differences existed in spinopelvic kinematics in high-level rowers without LBP in sweep and scull ergometer rowing. DESIGN: Repeated measures study. SETTING: Institute of Sport Laboratory. PARTICIPANTS: Ten high-level rowers. INTERVENTIONS: Kinematics of the pelvis, lower lumbar, upper lumbar, and lower thoracic regions during the drive phase of the rowing stroke were measured while rowing on an interchangeable sweep/scull ergometer. MAIN OUTCOME MEASURES: Total and segmental spinopelvic kinematics. RESULTS: Sweep rowing showed greater lateral bend (P < 0.05) throughout the stroke, which was predominately due to movement of the upper lumbar and lower thoracic regions. Furthermore, sweep rowing displayed a greater magnitude (P < 0.05) of axial rotation at the catch (created at the pelvis). Both sweep and scull rowing showed values close to end range flexion for the lower lumbar spine at the catch and early drive phases. No difference (P > 0.05) was evident in lateral bend or axial rotation values for the lower lumbar region. CONCLUSIONS: Some differences exist in spinopelvic kinematics between sweep and scull ergometer rowing. However, it may be speculated that the lack of differences in lateral bend and axial rotation at the lower lumbar spine in sweep rowing may represent an adaptive and protective approach of experienced rowers. This may be the focus of future research studies.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Pelve/fisiologia , Coluna Vertebral/fisiologia , Adolescente , Fenômenos Biomecânicos , Ergometria , Feminino , Humanos , Masculino , Rotação , Adulto Jovem
15.
Res Sports Med ; 18(2): 127-39, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20397115

RESUMO

It has been purported that inflammatory cytokines may be responsible for the aetiology of overtraining. The aim of the present study was to investigate the relationship between self-reported measures of overtraining and inflammatory cytokines. Eight elite male rowers were monitored in their natural training environment for 8 weeks prior to the 2007 Rowing World Championships. During this period of intense endurance training, self-report measures of overtraining and inflammatory cytokines (Interleukin (IL)-1beta, IL-6, IL-8, IL-10, IL-12p70, and Tumor Necrosis Factor (TNF)-alpha) were assessed fortnightly. Consistent with previous findings, proinflammatory cytokines IL-1beta and TNF-alpha were significantly associated (p

Assuntos
Atletas , Citocinas/sangue , Mediadores da Inflamação/sangue , Resistência Física , Adulto , Depressão/fisiopatologia , Fadiga/fisiopatologia , Humanos , Masculino , Transtornos do Sono-Vigília/fisiopatologia , Adulto Jovem
16.
J Sci Med Sport ; 13(3): 371-5, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19574100

RESUMO

This study examined the thermoregulatory responses in field hockey goalkeepers during games (Part A), and assessed the effect of heat stress on hockey-specific response time (Part B). In Part A, core temperature (T(c)), skin temperature (T(sk)), body mass, fluid consumption and heart rate (HR) responses of six goalkeepers during two premier level club games in the Western Australian (winter) hockey season were recorded. Part B assessed the same measures, plus a response time test on four goalkeepers playing a simulated game inside a climate chamber in cool (COOL: 20 degrees C, 40% RH) and hot (HOT: 35 degrees C, 40% RH) conditions. In Part A, the mean (+/-SD) T(c) and T(sk) measured in games was 38.49+/-0.20 degrees C and 34.99+/-0.99 degrees C, with increases from baseline of 1.34+/-0.19 degrees C and 1.08+/-0.30 degrees C, respectively. Most of the increase in T(c) resulted from the pre-game warm-up. In Part B, T(c) and T(sk) only increased significantly (p<0.05) from baseline in the HOT condition (0.62+/-0.18 degrees C and 1.61+/-0.82 degrees C, respectively). Response time was significantly slower (0.87+/-0.14s, p<0.01) after heat exposure, compared to COOL (0.75+/-0.15s), but the number of correct responses was not affected. For optimal performance, careful attention should be given to strategies to limit T(c) increases in field hockey goalkeepers during matches.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Hóquei , Temperatura Alta , Adulto , Feminino , Humanos , Masculino , Monitorização Fisiológica/métodos , Temperatura Cutânea , Sudorese/fisiologia , Austrália Ocidental , Adulto Jovem
17.
Res Sports Med ; 17(4): 245-59, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19967603

RESUMO

This study compared the effects of hot/cold water immersion, static stretching, and no recovery (control) interventions on leg strength, rowing performance, and indicators of muscle soreness/damage in the 72 hours following strenuous stair-climb running. Club (n = 14) and elite (Sports Institute) (n = 6) rowers performed the training run on three separate occasions. After each run, participants completed a randomly assigned 15-minute recovery treatment, either hot/cold, static stretching, or control, which were repeated at 24 and 48 hours postrun. No significant strength or performance differences existed between the three recovery treatments for either group. Muscle soreness for both groups remained significantly elevated (p < 0.05) above baseline at 72 hours postrun. At 48-hours postrun serum creatine kinase levels had returned to baseline and at 72 hours postrun were below baseline in both groups. In conclusion, neither hot/cold nor static stretching accelerated recovery at 72 hours beyond that achieved by the control condition.


Assuntos
Músculo Esquelético/fisiologia , Esforço Físico/fisiologia , Recuperação de Função Fisiológica/fisiologia , Corrida/fisiologia , Esportes/fisiologia , Análise de Variância , Fenômenos Biomecânicos , Creatina Quinase/sangue , Feminino , Humanos , Imersão , Perna (Membro)/fisiologia , Masculino , Exercícios de Alongamento Muscular , Dor/etiologia , Temperatura , Torque , Austrália Ocidental , Adulto Jovem
18.
Int J Sports Physiol Perform ; 4(2): 151-62, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19567919

RESUMO

Some reports suggest variation in physiological responses and athletic performance, for female athletes at specific phases of the menstrual cycle. However, inconsistent findings are common due to the inappropriate verification of menstrual cycle phase, small subject numbers, high intra- and interindividual variability in estrogen and progesterone concentration, and the pulsatile secretion of these hormones. Therefore, the oral contraceptive (OC) cycle may provide a more stable environment in which to evaluate the acute effect of reproductive hormones on physiological variables and exercise performance. To date, most of the OC research has compared differences between OC use and nonuse, and few researchers have examined within-cycle effects of the OC. It is also apparent that OC use is becoming far more prevalent in athletes; hence the effect of the different exogenous and endogenous hormonal profiles on athletic performance should be investigated. Research to date identifies potential for variation in aerobic performance, anaerobic capacity, anaerobic power and reactive strength throughout an OC cycle. The purpose of this review is to present and evaluate the current literature on the physiology of exercise and athletic performance during the OC cycle.


Assuntos
Desempenho Atlético , Anticoncepcionais Orais Combinados/uso terapêutico , Ciclo Menstrual/efeitos dos fármacos , Saúde da Mulher , Pesquisa Biomédica/tendências , Metabolismo Energético/efeitos dos fármacos , Estradiol/sangue , Feminino , Humanos , Ciclo Menstrual/sangue , Força Muscular/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Progesterona/sangue , Ventilação Pulmonar/efeitos dos fármacos
19.
Res Sports Med ; 17(2): 121-32, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19479630

RESUMO

Data on training of competitive athletes and the inflammatory response, and, more specifically, the utility of psychological inventories to monitor this response in regards to overreaching is limited. The aim of the present study was to investigate the association of the Perceived Stress Scale (PSS) and inflammatory markers in elite rowers. Eight rowers (males n = 4; females n = 4) were monitored over an 8-week training period, comprising 12 sessions each week and training an average 3.11 h.d(-1). Training volume was periodized weekly while intensity was maintained throughout the study. Perceived stress was measured weekly pretraining, and capillary blood samples (500 microL) were taken post-training. Significant associations between perceived stress and cytokines interleukin-6 (p < .05) and tumor necrosis factor alpha (p < .05) were observed. While further investigation of the role of cytokines in the overtraining process is required, these data provide preliminary support for an association between perceived stress and the inflammatory responses to training.


Assuntos
Citocinas/sangue , Educação Física e Treinamento , Resistência Física/fisiologia , Esportes/fisiologia , Estresse Fisiológico/fisiologia , Adolescente , Feminino , Humanos , Interleucina-6/sangue , Masculino , Fatores de Tempo , Fator de Necrose Tumoral alfa/sangue
20.
Med Sci Sports Exerc ; 41(5): 1138-45, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19346972

RESUMO

PURPOSE: This investigation assessed the effects of training intensity and ground surface type on hemolysis, inflammation, and hepcidin activity during running. METHODS: Ten highly trained male endurance athletes completed a graded exercise test, two continuous 10-km runs on a grass (GRASS) and a bitumen road surface (ROAD) at 75%-80% peak VO2 running velocity, and a 10 x 1-km interval running session (INT) at 90%-95% of the peak VO2 running velocity. Venous blood and urine samples were collected before, immediately after, and at 3 and 24 h after exercise. Serum samples were analyzed for circulating levels of IL-6, free hemoglobin (Hb), haptoglobin (Hp), iron, and ferritin. Urine samples were analyzed for changes in hepcidin expression. RESULTS: After running, the IL-6 and free Hb were significantly greater, and serum Hp was significantly lower than preexercise values in all three conditions (P < 0.05). Furthermore, IL-6 levels and the change in free Hb from baseline were significantly greater in the INT compared with those in the GRASS (P < 0.05). There were no differences between the GRASS and ROAD training surfaces (P > 0.05). Serum iron and ferritin were significantly increased after exercise in all three conditions (P < 0.05) but were not different between trials. CONCLUSION: Greater running intensities incur more inflammation and hemolysis, but these variables were not affected by the surface type trained upon.


Assuntos
Antibacterianos/biossíntese , Peptídeos Catiônicos Antimicrobianos/biossíntese , Hemólise/imunologia , Esforço Físico/fisiologia , Propriedades de Superfície , Citocinas , Teste de Esforço , Hepcidinas , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Corrida/fisiologia , Adulto Jovem
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