1
|
Doherty R, Madigan S, Nevill A, Warrington G, Ellis J. The impact of long haul travel on the sleep of elite athletes. Neurobiol Sleep Circadian Rhythms 2023; 15:100102. [PMID: 37766939 PMCID: PMC10520441 DOI: 10.1016/j.nbscr.2023.100102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 09/10/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023] Open
Abstract
In order to manage and implement strategies to alleviate the symptoms of jet lag it is essential to assess the impact of jet lag in athletes. The aim of this study was to assess the impact of long haul eastward travel on elite athletes' (n = 7 elite national track cyclists; male n = 3, and female n = 4) sleep. The athletes' sleep was monitored before, during and after travel using both actigraphy and self-report measures. Participants wore an activity monitor for 5 days prior to travel, during the long haul travel and 5 days upon arrival at their destination and completed a daily online sleep diary Actigraphy highlighted significant reductions in time in bed, total sleep time and sleep efficiency (%) due to long haul eastward travel, particularly in the 48 h after travel. Sleep diary data exhibited significant reductions in time in bed, total sleep time, sleep efficiency, sleep quality and a significant increase in fatigue going to bed as a result of long haul eastward travel. In order to facilitate the development of interventions to reduce the symptoms and severity of jet lag objective and subjective assessments of sleep should be coupled with assessments of chronotype and perceived sleep need.
Collapse
Affiliation(s)
- R. Doherty
- Sports Lab North West, Atlantic Technological University, Letterkenny Campus, F92 FC93 Donegal, Ireland
- Sport Ireland Institute, National Sports Campus, Abbotstown, D15 PNON, Ireland
| | - S.M. Madigan
- Sport Ireland Institute, National Sports Campus, Abbotstown, D15 PNON, Ireland
| | - A. Nevill
- Faculty of Education, Health and Wellbeing, University of Wolverhampton, Walsall Campus, Walsall, WV1 1LY, UK
| | - G. Warrington
- Sport and Human Performance Research Centre, Schuman Building, University of Limerick, V94 T9PX, Ireland
- Department of Physical Education and Sport Sciences, University of Limerick, V94 T9PX, Ireland
| | - J.G. Ellis
- Northumbria Centre for Sleep Research, Northumbria University, Newcastle, NE7 7XA, UK
| |
Collapse
|
2
|
Meng C, Rui W. SECURITY ANALYSIS OF SPORTS COMPETITION UNDER THE INFLUENCE OF COVID-19. REV BRAS MED ESPORTE 2023. [DOI: 10.1590/1517-8692202329012022_0547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
ABSTRACT Introduction The continuous growth of COVID-19 has harmed sports competitions. Although the existing method of non-opening to spectators is very effective for preventing and controlling COVID-19, it will also seriously blow the sports economy’s development. Objective Explore the safety of sports competition under the influence of COVID-19 to realize sports practice in a safe and regulated condition. Methods Firstly, the current public’s willingness to participate in the competition was analyzed by questionnaire survey. Then, using the literature search method, this paper discusses the safety needs of sports competitions under the normalization of the prevention and control of COVID-19 in the research area at the present stage. Results By completely controlling the crowd shift rule and skillfully controlling the crowd pace, the transmission risk in the competition process can be effectively reduced. Conclusion The relevant departments and stadium managers should fully analyze the current epidemic prevention and control needs and strengthen spectator safety management in the study area in combination with regional characteristics and the actual spectator situation. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.
Collapse
Affiliation(s)
- Chen Meng
- Northeast Agricultural University, China
| | - Wang Rui
- Northeast Agricultural University, China
| |
Collapse
|
3
|
Orysiak J, Młynarczyk M, Piec R, Jakubiak A. Lifestyle and environmental factors may induce airway and systemic inflammation in firefighters. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:73741-73768. [PMID: 36094704 PMCID: PMC9465149 DOI: 10.1007/s11356-022-22479-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 08/07/2022] [Indexed: 06/15/2023]
Abstract
Health status depends on multiple genetic and non-genetic factors. Nonheritable factors (such as lifestyle and environmental factors) have stronger impact on immune responses than genetic factors. Firefighters work is associated with exposure to air pollution and heat stress, as well as: extreme physical effort, mental stress, or a changed circadian rhythm, among others. All these factors can contribute to both, short-term and long-term impairment of the physical and mental health of firefighters. Increased levels of some inflammatory markers, such as pro-inflammatory cytokines or C-reactive protein (CRP) have been observed in firefighters, which can lead to local, acute inflammation that promotes a systemic inflammatory response. It is worth emphasizing that inflammation is one of the main hallmarks of cancer and also plays a key role in the development of cardiovascular and respiratory diseases. This article presents possible causes of the development of an inflammatory reaction in firefighters, with particular emphasis on airway inflammation caused by smoke exposure.
Collapse
Affiliation(s)
- Joanna Orysiak
- Central Institute for Labour Protection - National Research Institute, Czerniakowska St. 16, 00-701, Warsaw, Poland.
| | - Magdalena Młynarczyk
- Central Institute for Labour Protection - National Research Institute, Czerniakowska St. 16, 00-701, Warsaw, Poland
| | - Robert Piec
- Institute of Internal Security, The Main School of Fire Service, Słowackiego St. 52/54, 01-629, Warsaw, Poland
| | - Agnieszka Jakubiak
- Department of Heart Failure and Cardiac Rehabilitation, Medical University of Warsaw, Żwirki and Wigury St. 61, 02-091, Warsaw, Poland
| |
Collapse
|
4
|
Alkemade P, Gerrett N, Daanen HAM, Eijsvogels TMH, Janssen TWJ, Keaney LC. Heat acclimation does not negatively affect salivary immunoglobulin-A and self-reported illness symptoms and wellness in recreational athletes. Temperature (Austin) 2022; 9:331-343. [PMID: 36339091 PMCID: PMC9629114 DOI: 10.1080/23328940.2022.2088029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Heat acclimation (HA) protocols repeatedly expose individuals to heat stress. As HA is typically performed close to the pinnacle event, it is essential that the protocol does not compromise immune status, health, or wellbeing. The purpose of this study was to examine the effect of HA on resting salivary immunoglobulin-A (s-IgA) and salivary cortisol (s-cortisol), self-reported upper-respiratory tract symptoms, and self-reported wellness parameters. Seventeen participants (peak oxygen uptake 53.2 ± 9.0 mL·kg−1·min−1) completed a 10-day controlled-hyperthermia HA protocol, and a heat stress test both before (HST1) and after (HST2) HA (33°C, 65% relative humidity). Resting saliva samples were collected at HST1, day 3 and 7 of the HA protocol, HST2, and at 5 ± 1 days post-HA. Upper-respiratory tract symptom data were collected weekly from one week prior to HA until three weeks post HA, and wellness ratings were reported daily throughout HA. HA successfully induced physiological adaptations, with a lower end-exercise rectal temperature and heart rate and higher whole-body sweat rate at HST2 compared to HST1. In contrast, resting saliva flow rate, s-IgA concentration, s-cortisol concentration, and s-cortisol secretion rate remained unchanged (n = 11–14, P = 0.10–0.48). Resting s-IgA secretion rate increased by 39% from HST1 to HST2 (n = 14, P = 0.03). No changes were observed in self-reported upper respiratory tract symptoms and wellness ratings. In conclusion, controlled-hyperthermia HA did not negatively affect resting s-IgA and s-cortisol, self-reported upper-respiratory tract symptoms, and self-reported wellness parameters in recreational athletes.
Collapse
Affiliation(s)
- Puck Alkemade
- Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Nicola Gerrett
- Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
- Gentherm, Northville, MI, USA
| | - Hein A. M. Daanen
- Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Thijs M. H. Eijsvogels
- Radboud Institute for Health Sciences, Department of Physiology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Thomas W. J. Janssen
- Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Lauren C. Keaney
- Sports Performance Research Institute New Zealand, Auckland University of Technology, Auckland, New Zealand
- Defence Technology Agency, New Zealand Defence Force, Auckland, New Zealand
| |
Collapse
|
5
|
Abstract
AbstractUpper respiratory tract infections (“common cold”) are the most common acute illnesses in elite athletes. Numerous studies on exercise immunology have proposed that intense exercise may increase susceptibility to respiratory infections. Virological data to support that view are sparse, and several fundamental questions remain. Immunity to respiratory viral infections is highly complex, and there is a lack of evidence that minor short- or long-term alterations in immunity in elite athletes have clinical implications. The degree to which athletes are infected by respiratory viruses is unclear. During major sport events, athletes are at an increased risk of symptomatic infections caused by the same viruses as those in the general population. The symptoms are usually mild and self-limiting. It is anecdotally known that athletes commonly exercise and compete while having a respiratory viral infection; there are no virological studies to suggest that such activity would affect either the illness or the performance. The risk of myocarditis exists. Which simple mitigation procedures are crucial for effective control of seasonal respiratory viral infections is not known.
Collapse
|
6
|
Yamaguchi T, Kubota M, Naruse H, Kuwatsuru K, Miyazaki T. Injuries and Illnesses Observed in Athletes from Beginner to Elite Levels at the 18th National Sports Festival for Persons with Disabilities in Japan. Prog Rehabil Med 2021; 6:20210032. [PMID: 34514182 PMCID: PMC8385550 DOI: 10.2490/prm.20210032] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 08/04/2021] [Indexed: 12/26/2022] Open
Abstract
Objectives : This study aimed to describe the injuries and illnesses that occurred at the 18th
National Sports Festival for Persons with Disabilities in Japan, which was attended by
more than 3000 athletes from beginner to elite levels. Methods : Records from medical stations set up at the venues for each sport were reviewed. The
incidence rates (IRs) were calculated as the number of medical station visits per 1000
athlete-days. The backgrounds of injuries and illnesses were investigated. Results : In total, 3277 athletes attended the festival, and 134 eligible medical station
visits were analyzed. Overall, 102 athletes complained of injuries. For the whole
schedule of the festival, IRs were 15.5 for injuries and illnesses and 11.8 for injuries
alone. For injuries and illnesses, high IRs were seen in soccer (39.8), basketball
(25.6), and foot baseball (22.4); for injuries alone, high IRs were also seen in soccer
(33.6), basketball (25.6), and foot baseball (16.8). The most frequent symptoms were
internal symptoms (n=32), contusions (n=30), and wounds (n=24). Joint sprains occurred
in various sports, whereas muscle strains happened mainly in disciplines demanding
sprinting or high agility. Of the 55 cases that occurred during events or public
rehearsals, 45 were traumatic, whereas the relation to sports activities was not
described in 51 cases. Of participants with internal symptoms, 11 were suggested to have
viral infections. We identified 21 injuries caused by falls. Conclusions : Minor trauma and viral infection were the most frequently observed symptoms among
injuries and illnesses, respectively. Structured medical records and organized
surveillance systems should be utilized to improve data collection and understand the
onset of injury and illness.
Collapse
Affiliation(s)
- Tomoko Yamaguchi
- Department of Orthopaedic Surgery, Kanazawa University Hospital, Kanazawa, Japan
| | - Masafumi Kubota
- Department of Physical Therapy; Graduate Course of Rehabilitation Science; School of Health Sciences; College of Medical, Pharmaceutical, and Health Sciences; Kanazawa University; Kanazawa; Japan
| | - Hiroaki Naruse
- Division of Physical Therapy and Rehabilitation, University of Fukui Hospital, Fukui, Japan
| | | | - Tsuyoshi Miyazaki
- Department of Orthopaedics and Rehabilitation Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| |
Collapse
|
7
|
Cardinale M. Preparing athletes and staff for the first "pandemic" Olympic Games. J Sports Med Phys Fitness 2021; 61:1052-1060. [PMID: 34256538 DOI: 10.23736/s0022-4707.21.12745-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) is the virus causing Coronavirus disease 2019 (COVID-19). Since the World Health Organization declared the outbreak of pandemic on March 11, 2020, cases have been increasing around the World with more than 3-million deaths recorded and a daily number of COVID-19 cases 20 times higher than when the Olympics were postponed, at the time of writing. Governments adopted various lockdown measures forcing isolation for many weeks/months depending on the evolution of the disease in each country. The rapid transmission of the disease forced the Tokyo 2020 Olympics to be postponed for one year. Travel restrictions, quarantine requirements and isolation have been the norm for many athletes in preparation for the Olympic Games. Also, due to the measures put in place to reduce the spread of the disease, sporting facilities have been closed and competitions cancelled forcing athletes and their staff to find alternative solutions to maintain performance and continue preparing for the Olympics. This unique challenge is affecting the whole World, and while vaccination programs start to be deployed, in a few months the world will see the first Olympic Games' edition during a pandemic. The aim of this special paper was to consider the various challenges posed by the COVID pandemic and to provide information for coaching support staff to improve the preparation for Tokyo Olympics as well as consider the possible performance implications of this unique Olympic edition.
Collapse
Affiliation(s)
- Marco Cardinale
- Department of Research and Scientific Support, Aspetar Orthopedic and Sports Medicine Hospital, Doha, Qatar - .,Department of Surgery and Interventional Medicine, Institute of Sport Exercise and Health, University College London, London, UK -
| |
Collapse
|
8
|
Doherty R, Madigan SM, Nevill A, Warrington G, Ellis JG. The Sleep and Recovery Practices of Athletes. Nutrients 2021; 13:nu13041330. [PMID: 33920560 PMCID: PMC8072992 DOI: 10.3390/nu13041330] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 04/14/2021] [Accepted: 04/15/2021] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Athletes maintain a balance between stress and recovery and adopt recovery modalities that manage fatigue and enhance recovery and performance. Optimal TST is subject to individual variance. However, 7-9 h sleep is recommended for adults, while elite athletes may require more quality sleep than non-athletes. METHODS A total of 338 (elite n = 115, 74 males and 41 females, aged 23.44 ± 4.91 years; and sub-elite n = 223, 129 males and 94 females aged 25.71 ± 6.27) athletes were recruited from a variety of team and individual sports to complete a battery of previously validated and reliable widely used questionnaires assessing sleep, recovery and nutritional practices. RESULTS Poor sleep was reported by both the elite and sub-elite athlete groups (i.e., global PSQI score ≥5-elite 64% [n = 74]; sub-elite 65% [n = 146]) and there was a significant difference in sport-specific recovery practices (3.22 ± 0.90 vs. 2.91 ± 0.90; p < 0.001). Relatively high levels of fatigue (2.52 ± 1.32), stress (1.7 ± 1.31) and pain (50%, n = 169) were reported in both groups. A range of supplements were used regularly by athletes in both groups; indeed, whey (elite n = 22 and sub-elite n = 48) was the most commonly used recovery supplement in both groups. Higher alcohol consumption was observed in the sub-elite athletes (12%, n = 26) and they tended to consume more units of alcohol per drinking bout. CONCLUSION There is a need for athletes to receive individualised support and education regarding their sleep and recovery practices.
Collapse
Affiliation(s)
- Rónán Doherty
- Sports Lab North West, Letterkenny Institute of Technology, Port Road, Letterkenny, F92 FC93 Donegal, Ireland
- Sport Ireland Institute, National Sport Campus, Abbotstown, D15 PNON Dublin, Ireland;
- Northumbria Centre for Sleep Research, Northumbria University, Newcastle NE7 7XA, UK;
- Correspondence:
| | - Sharon M. Madigan
- Sport Ireland Institute, National Sport Campus, Abbotstown, D15 PNON Dublin, Ireland;
| | - Alan Nevill
- Faculty of Education, Health and Wellbeing, University of Wolverhampton, Walsall Campus, Walsall WV1 1LY, UK;
| | - Giles Warrington
- Health Research Institute, Schuman Building, University of Limerick, V94 T9PX Limerick, Ireland;
- Department of Physical Education and Sport Sciences, University of Limerick, V94 T9PX Limerick, Ireland
| | - Jason G. Ellis
- Northumbria Centre for Sleep Research, Northumbria University, Newcastle NE7 7XA, UK;
| |
Collapse
|
9
|
Davison G, Perkins E, Jones AW, Swart GM, Jenkins AR, Robinson H, Dargan K. Coldzyme® Mouth Spray reduces duration of upper respiratory tract infection symptoms in endurance athletes under free living conditions. Eur J Sport Sci 2020; 21:771-780. [PMID: 32419645 DOI: 10.1080/17461391.2020.1771429] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Upper respiratory tract infection (URTI) can compromise athlete preparation and performance, so countermeasures are desirable. The aim of this study was to assess the effects of ColdZyme® Mouth Spray (ColdZyme) on self-reported upper respiratory tract infection in competitive endurance athletes under free-living conditions. One hundred and twenty-three endurance-trained, competitive athletes (recruited across 4 sites in England, UK) were randomised to control (no treatment, n = 61) or ColdZyme (n = 62) for a 3-month study period (between December 2017 and March 2018; or December 2018 and April 2019). They recorded daily training and illness symptoms (Jackson common cold questionnaire) during the study period. A total of 130 illness episodes were reported during the study with no difference in incidence between groups (episodes per person: 1.1 ± 0.9 Control, 1.0 ± 0.8 ColdZyme, P = 0.290). Episode duration was significantly shorter in ColdZyme compared to Control: Control 10.4 ± 8.5 days vs. ColdZyme 7.7 ± 4.0 days, P = 0.016). Further analysis to compare episodes with poor vs. good compliance with ColdZyme instructions for use (IFU) within the ColdZyme group showed a greater reduction in duration of URTI when compliance was good (9.3 ± 4.5 days in ColdZyme poor IFU compliance vs. 6.9 ± 3.5 days in ColdZyme good IFU compliance, P = 0.040). ColdZyme may be an effective countermeasure to reduce URTI duration, which was significantly lower (by 26-34%) in the ColdZyme treatment group (with no influence on incidence). This may have implications for athlete performance.
Collapse
Affiliation(s)
- Glen Davison
- Endurance Research Group, School of Sport & Exercise Sciences, University of Kent, Canterbury, UK
| | - Eleanor Perkins
- Endurance Research Group, School of Sport & Exercise Sciences, University of Kent, Canterbury, UK
| | - Arwel W Jones
- Lincoln Institute for Health, University of Lincoln, Lincoln, UK
| | - Gabriella M Swart
- Endurance Research Group, School of Sport & Exercise Sciences, University of Kent, Canterbury, UK
| | - Alex R Jenkins
- Lincoln Institute for Health, University of Lincoln, Lincoln, UK
| | - Hayley Robinson
- Lincoln Institute for Health, University of Lincoln, Lincoln, UK
| | - Kimberly Dargan
- Endurance Research Group, School of Sport & Exercise Sciences, University of Kent, Canterbury, UK
| |
Collapse
|
10
|
Guerreiro RDC, Silva A, Andrade HDA, Biasibetti IG, Vital R, Silva HGVD, Silva FRD, Mello MTD. WAS POSTPONING THE TOKYO 2020 OLYMPIC AND PARALYMPIC GAMES A CORRECT DECISION? REV BRAS MED ESPORTE 2020. [DOI: 10.1590/1517-8692202026030036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
ABSTRACT In December 2019, Wuhan, in China, attracted international attention due to a pneumonia outbreak caused by the new coronavirus (2019-nCoV). Infection by 2019-nCoV is more likely in elderly people with comorbidities or with associated chronic diseases. Due to the high transmission rate among humans, this disease is rapidly disseminated, which led to several events being canceled, including the Tokyo 2020 Olympic and Paralympic Games. The aim of this article is to discuss the risk factors for Olympic and Paralympic athletes, as well as for spectators, that justify the decision to postpone the Tokyo Games 2020. Regular physical exercise is associated with health and the prevention of chronic diseases. Although athletes generally appear to be healthy and physically fit, this may not be true. The immune system, which protects the organism from invasive microorganisms, can be affected by the duration and quality of sleep, as well as by physical exercise which influences the quality of the immune response. High volumes of high-intensity physical exercise, as well as changes in sleep patterns during the pre-competition period and the impacts of jet lag on athletes traveling for the Tokyo Games in 2020 may lead to immune system suppression, making these groups more vulnerable to infection by 2019-nCoV. Moreover, during the period planned for the games in 2020 the pandemic may be subsiding in some countries and increasing in others, and this was also taken into consideration as a risk factor. Hence, the decision taken to postpone the Tokyo 2020 Olympic and Paralympic Games until 2021 due to the 2019-nCoV was the correct one, and was extremely important to protect the health of Olympic and Paralympic athletes, as well as spectators. Level of evidence V; expert opinion .
Collapse
|
11
|
Acute hyperketonaemia alters T-cell-related cytokine gene expression within stimulated peripheral blood mononuclear cells following prolonged exercise. Eur J Appl Physiol 2019; 120:191-202. [PMID: 31729600 DOI: 10.1007/s00421-019-04263-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Accepted: 11/08/2019] [Indexed: 12/22/2022]
Abstract
PURPOSE We investigated the effect of the racemic β-hydroxybutyrate precursor, R,S-1,3-butanediol (BD), on T-cell-related cytokine gene expression within stimulated peripheral blood mononuclear cells (PBMC) following prolonged, strenuous exercise. METHODS A repeated-measures, randomised, crossover study was conducted in nine healthy, trained male cyclists (age, 26.7 ± 5.2 years; VO2peak, 63.9 ± 2.5 mL kg-1 min-1). Participants ingested 0.35 g kg-1 of BD or placebo 30 min before and 60 min during 85 min of steady-state (SS) exercise, which preceded a ~ 30 min time-trial (TT) (7 kJ kg-1). Blood samples were collected at pre-supplement, pre-exercise, post-SS, post-TT and 1-h post-TT. Whole blood cultures were stimulated with Staphylococcal enterotoxin B (SEB) for 24 h to determine T-cell-related interleukin (IL)-4, IL-10 and interferon (IFN)-γ mRNA expression within isolated PBMCs in vitro. RESULTS Serum cortisol, total circulating leukocyte and lymphocyte, and T-cell subset concentrations were similar between trials during exercise and recovery (all p > 0.05). BD ingestion increased T-cell-related IFN-γ mRNA expression compared with placebo throughout exercise and recovery (p = 0.011); however, IL-4 and IL-10 mRNA expression and the IFN-γ/IL-4 mRNA expression ratio were unaltered (all p > 0.05). CONCLUSION Acute hyperketonaemia appears to transiently amplify the initiation of the pro-inflammatory T-cell-related IFN-γ response to an immune challenge in vitro during and following prolonged, strenuous exercise; suggesting enhanced type-1 T-cell immunity at the gene level.
Collapse
|