The effects of exercise in the heat and hydration status on cognitive function
| ISRCTN | ISRCTN95800060 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN95800060 |
| Secondary identifying numbers | FHITP |
- Submission date
- 05/09/2016
- Registration date
- 23/09/2016
- Last edited
- 24/10/2019
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Other
Plain English summary of protocol
Background and study aims
Many major international competitions for field hockey take place in hot environmental conditions (such as in the Rio 2016 Olympics). There is therefore a need to better understand how the body copes with the heat stress associated with high-intensity intermittent (stop-start) exercise and how this impacts upon field-hockey players’ physical performance and cognitive function (mental processing). Field hockey not only involves intermittent high speed running and sprinting but decision-making skills. Therefore it is important to understand how field-hockey specific exercise in hot conditions effects cognitive function. In addition, previous research from our lab has demonstrated that field hockey player compete when dehydrated, particularly during tournaments. The aim of this study is to determine whether cognitive function is impaired in hot and moderate conditions and when dehydrated following hockey specific exercise.
Who can participate?
Female elite field hockey players aged 18-40.
What does the study involve?
Participants complete four field hockey simulations in a random order, a minimum of 1 week apart, on a treadmill. Before and after each of the hockey match simulations cognitive function is assessed using laptop based software. The four simulations involve exercise in the heat in a normal hydration state; exercise in the heat when dehydrated; exercise in moderate conditions in a normal hydration state; and exercise in moderate conditions in a dehydrated state. Participants are familiarised with all the techniques and measurements during preliminary laboratory visits. For each simulation, participants have their cognitive function measured before and after each exercise test. In addition, their rectal temperature, how much they felt they are pushing themselves and thirst are measured every 10 minute during exercise.
What are the possible benefits and risks of participating?
Participants benefit from being provided with information about their current fitness levels and a training programme provided should they wish. In addition, information can be provided regarding a participant’s responses to exercising in hot conditions. Intermittent exercise in the heat is physically very demanding, and places strain on the body. Therefore, there is a risk that participants may feel faint or nauseas and/or suffer from heat stroke. All participants will be closely monitored in order to avoid this.
Where is the study run from?
Nottingham Trent University (UK)
When is the study starting and how long is it expected to run?
September 2006 to September 2008
Who is funding the study?
Nottingham Trent University (UK)
Who is the main contact?
Dr Caroline Sunderland
caroline.sunderland@ntu.ac.uk
Contact information
Scientific
Erasmus Darwin Building
Nottingham Trent University
Clifton Lane
Nottingham
NG11 8NS
United Kingdom
| Phone | +44 115 8486379 |
|---|---|
| caroline.sunderland@ntu.ac.uk |
Study information
| Study design | Single-centre randomised cross over trial |
|---|---|
| Primary study design | Interventional |
| Secondary study design | Randomised cross over trial |
| Study setting(s) | Other |
| Study type | Other |
| Participant information sheet | No participant information sheet available |
| Scientific title | Effects of heat stress and dehydration on cognitive function in elite female field hockey players |
| Study objectives | Cognitive function would be impaired when hypohydrated and under heat stress. |
| Ethics approval(s) | Nottingham Trent University School of Science and Technology Human Ethics Committee, 14/11/2006, ref: xxxviii |
| Health condition(s) or problem(s) studied | Sports performance |
| Intervention | Participants are randomised to undertake four exercise conditions in a random order. The exercise undertaken consists of 50 minutes of activity, divided into 2 x 25 min blocks of exercise separated by a 10 min intermission designed to replicate half time. This is performed on a motorised treadmill (h/p/cosmos Pulsar 4.0, Nussdorf-Traunstein, Germany) housed in an environmental chamber (WIR52-20HS, Design Environmental Ltd., Gwent, Wales, U.K) and consisted of different exercise intensities observed in match-play. Participants are required to hold a hockey stick for the entire duration of the protocol. The treadmill gradient was set at 1% to reflect the energy cost of outdoor running. Condition 1: Participants complete exercise in heat (33.3 ± 0.1oC, 59 ± 1% rh) in a dehydrated state (achieved through undergoing a period in an chamber (~ 40oC, 75% rh)) Condition 2: Participants complete exercise in heat (33.3 ± 0.1oC, 59 ± 1% rh) in a hydrated state (ingestion of water ad libitum, in a thermally neutral environment (~ 19oC) for ~ 2 hours) Condition 3: Participants complete exercise in a thermally neutral environment (~ 19oC) in a dehydrated state Condition 4: Participants complete exercise in a thermally neutral environment (~ 19oC) in a hydrated state All participants are monitored closely throughout the recovery period on completion of the main trials. Participants are fed, rehydrated and only permitted to leave the laboratory once they were euhydrated, core temperature had returned to normal levels and the participants confirmed they were feeling ‘normal’. Participants undergo computerised cognitive function assessments at baseline and 60- minutes post-exercise in all four trial conditions. Additionally, rectal temperature, perceived exertion (self-reported) and perceived thirst (self-reported) are measured at baseline and every 10 minutes throughout exercise in each condition. |
| Intervention type | Other |
| Primary outcome measure | Cognitive function is assessed using the Stroop test, visual search (VS) test and Sternberg Working memory test before and 60 minutes after each exercise condition. |
| Secondary outcome measures | 1. Rectal temperature recorded at baseline (time point 0) and every 10 minutes throughout exercise and immediately after completion of the final cognitive test battery in each exercise condition 2. Rating of perceived exertion on a scale of 6-20 using the Borg scale recorded at time point 0 and every 10 minutes throughout exercise in each exercise condition 3. Rating of perceived thirst (9 point scale ranging from not thirsty to very, very thirst) at time point 0 and every 10 minutes throughout exercise in each exercise condition |
| Overall study start date | 01/09/2006 |
| Completion date | 01/09/2008 |
Eligibility
| Participant type(s) | Healthy volunteer |
|---|---|
| Age group | Adult |
| Lower age limit | 18 Years |
| Upper age limit | 40 Years |
| Sex | Female |
| Target number of participants | 10 |
| Key inclusion criteria | 1. 18-40 years old 2. Female elite 3. Elite field hockey players |
| Key exclusion criteria | 1. Exercise-induced asthmatics 2. History of heart problems 3. Family history of sudden death below the age of 50 |
| Date of first enrolment | 01/12/2006 |
| Date of final enrolment | 01/09/2007 |
Locations
Countries of recruitment
- England
- United Kingdom
Study participating centre
Clifton Campus
Nottingham
NG11 8NS
United Kingdom
Sponsor information
University/education
Erasmus Darwin Building
Clifton Lane
Nottingham
NG11 8NS
England
United Kingdom
| Phone | +44 115 9418418 |
|---|---|
| sstenquiries@ntu.ac.uk | |
| Website | www.ntu.ac.uk |
"ROR" |
https://ror.org/04xyxjd90 |
Funders
Funder type
University/education
Private sector organisation / Universities (academic only)
- Alternative name(s)
- NTU
- Location
- United Kingdom
Results and Publications
| Intention to publish date | 31/07/2017 |
|---|---|
| Individual participant data (IPD) Intention to share | Yes |
| IPD sharing plan summary | Available on request |
| Publication and dissemination plan | Planned publication in a peer-reviewed journal. |
| IPD sharing plan |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Results article | results | 19/06/2018 | 24/10/2019 | Yes | No |
Editorial Notes
24/10/2019: Publication reference added.
