ANZCTR - Registration

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Trial registered on ANZCTR

Registration number

ACTRN12606000470594

Ethics application status

Approved

Date submitted

7/11/2006

Date registered

13/11/2006

Date last updated

13/11/2006

Type of registration

Prospectively registered

Titles & IDs

Public title

Paediatric Exercise and Cardiac Performance Study

Scientific title

A randomised controlled trial of the effect of plasma volume on cardiac performance during short-term high intensity exercise among high school adolescents.

Universal Trial Number (UTN)

Trial acronym

Linked study record

Health condition

Health condition(s) or problem(s) studied:

Cardiac performance in high school adolescents

Condition category

Condition code

Cardiovascular

Normal development and function of the cardiovascular system

Intervention/exposure

Study type

Interventional

Description of intervention(s) / exposure

Oral fluid loading using sport drinks (Gatorade R) immediately prior to exercise. Gatorade is a about half normal saline with 8% dextrose. On average for each 100 mL it contains Carbohydrate 6.3g;], Sodium 47mg, and Potassium 22.5mg.

A single session baseline exercise assessment will be conducted 1 week before the intervention. Each subject will be perform a running exercise in the upright position on a treadmill (TrackmasterR TMX425 treadmill) with a complete penal of metabolic parameters collected using the MedgraphicsR CPX/D breath by breath gas exchange system. Subjects will be evaluated according to the Bruce protocol to the point of exhaustion usually 25-30 minutes after the warm-up period.

At the retesting session, subjects in the treatment group will receive Gatorade 20mL/Kg 15 minutes prior to the exercise assessment. The same routine of exercise will be performed by each subject and in the same manner as the baseline session.

Intervention code [1]

Other interventions

Comparator / control treatment

Subjects in the control group will not be pre-loaded with oral fluid before exercise.

Control group

Active

Outcomes

Primary outcome [1]

The main outcomes of the study are the cardiac function measurements using the change of stroke volume SV (mL/beat) as the primary indicator. Fifteen minutes prior to the retesting exercise session, subjects in the treatment group will be pre-loaded with oral fluid. The difference between the baseline and retesting measures will be calculated as the change in SV. All cardiac function measurements will be made through a transcutaneous approach using the Ultrasonic Cardiac Output Monitor (USCOM) using a 3.3 hertz transducer.

Timepoint [1]

The stroke volume will be assessed at the single baseline exercise session, as well as the single retesting exercise session. At each session the SV will be measured at the following timepoints: 1) at a resting stage immediately before the exercise; 2) at a significant exercise stage (30% VO2max); 3) at a sub-maximal stage (50% VO2max); 4) at a maximal exercise stage (75%VO2max); 5) at the point of exhaustion; and 6) 3 minutes post exercise.

Secondary outcome [1]

Secondary outcomes include cardiac output (L/min), Cardiac Index (L/min/m2).

Timepoint [1]

These outcomes will be assessed at the single baseline exercise session, as well as the single retesting exercise session. At each session these outcomes will be measured at the following timepoints: 1) at a resting stage immediately before the exercise; 2) at a significant exercise stage (30% VO2max); 3) at a sub-maximal stage (50% VO2max); 4) at a maximal exercise stage (75%VO2max); 5) at the point of exhaustion; and 6) 3 minutes post exercise. Fifteen minutes prior to the retesting exercise session, subjects in the treatment group will be pre-loaded with oral fluid. The difference between the baseline and retesting measures will be calculated as the change in SV. All cardiac function measurements will be made through a transcutaneous approach using the Ultrasonic Cardiac Output Monitor (USCOM) using a 3.3 hertz transducer.

Eligibility

Key inclusion criteria

High school adolescents, both males and females, aged between 12 and 16 years who are physically fit and are free of known illnesses or diseases that may affect their exercise ability. Due to the fact that the study is specifically aiming to develop hydration strategies for elite and even professional sports players and young people who usually involve in high intensity exercise, ordinary adolescents are not considered as the target population. Potential subjects will be recruited only from regional high schools that are designated as centres of excellence for Sports, hence, the inclusion criteria are the high school students aged between 12 and 16 years who are attending one of the regional Sports High School within the catchment areas of he Sydney West Area Health Services.

Minimum age

12 Years

Maximum age

16 Years

Sex

Both males and females

Can healthy volunteers participate?

Key exclusion criteria

Students who are diagnosed with any chronic illnesses and diseases that may affect their exercise ability and students who are diagnosed as over weight and obese will not be included in the study.

Study design

Purpose of the study

Prevention

Allocation to intervention

Randomised controlled trial

Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)

Allocation is not concealed

Methods used to generate the sequence in which subjects will be randomised (sequence generation)

Stratifed allocation according to age and gender in the target population

Masking / blinding

Blinded (masking used)

Who is / are masked / blinded?

Intervention assignment

Parallel

Other design features

The exercise physiologist who will be conducting the exercise assessment is blinded to the treatment status of the subjects

Phase

Type of endpoint/s

Efficacy

Statistical methods / analysis

Recruitment

Recruitment status

Not yet recruiting

Date of first participant enrolment

Anticipated

1/01/2007

Actual

Date of last participant enrolment

Anticipated

Actual

Date of last data collection

Anticipated

Actual

Sample size

Target

350

Accrual to date

Final

Recruitment in Australia

Recruitment state(s)

Funding & Sponsors

Funding source category [1]

Commercial sector/Industry

Name [1]

Gatorade International

Address [1]

Country [1]

Primary sponsor type

Individual

Name

Gary J Browne

Address

Country

Secondary sponsor category [1]

None

Name [1]

Nil

Address [1]

Country [1]

Ethics approval

Ethics application status

Approved

Ethics committee name [1]

The Children's Hospital at Westmead Ethics Committee

Ethics committee address [1]

Ethics committee country [1]

Australia

Date submitted for ethics approval [1]

Approval date [1]

03/03/2006

Ethics approval number [1]

2005/106

Summary

Brief summary

The health benefits of proper hydration have long been recognized. A major component of the hydration process involves thirst which, depending on drinking availability, leads to voluntary fluid intake.  Exercising to fatigue (which commonly occurs in adolescent athletes) creates conditions that are similar to acute dehydration. Acutely, fluid restoration is effective in restoring fluid balance in these situations and improving exercise performance. 
Adolescent athletes are particularly prone to the effects of acute dehydration during exercise.  They frequently remain unaware or simply ignore thirst during exercise which may result in significant dehydration leading to poor exercise performance. The physiological effects of dehydration are well documented in athletes. In particular acute dehydration with exercise results in impaired of cardiac performance and inefficient oxygen delivery to the tissues, being a critical factor in severely limiting peak exercise performance very early on in exercise. The most important issue to remember here is that this impairment in exercise performance is preventable with an appropriate hydration strategy.  
Strategies utilizing oral fluid loading using sports drinks immediately prior to exercise have the potential to reduce the negative effects that early dehydration may have on cardiac performance. Current research supports a continued increase in Stroke Volume (SV) during exercise. This increase may well be augmented in adolescent athletes by a hydration strategy that preloads with oral fluid immediately prior to exercise.  This is the underlying hypothesis of the study. If the hypothesis is proven to be correct, that preloading with oral fluid improves cardiac performance in adolescent athletes then the same can be said of older children during exercise. We would then have a scientifically proven hydration strategy for use in older children to prevent early dehydration with exercise and produce maximum exercise performance.
This is a blinded randomise controlled trial involving 350 childhood athletes attending sports high schools in the Sydney West region. Participants are initially randomised to two groups.  All participants are evaluated at baseline for hydration status, aerobic exercise and cardiac performance.  The participants are then reevaluated 1 week later with hydration status controlled 24 hours prior to retesting. One group will be the intervention group (being preloaded immediately prior to exercise with oral fluid equivalent to half normal saline) and will receive GatoradeR   20mL/kg 15 minutes prior to exercise. All participants are then retested to determine differences in hydration status, aerobic exercise performance and cardiac performance between groups.

Trial website

Trial related presentations / publications

Public notes

Contacts

Principal investigator

Name

Address

Country

Phone

Fax

Contact person for public queries

Name

Gary J Browne

Address

Corner Hawkesbury Road
and Hainsworth Street
Locked Bag 4001
Westmead NSW 2145

Country

Australia

Phone

(02) 9845 0761

Fax

[email protected]

Contact person for scientific queries

Name

Gary J Browne

Address

Corner Hawkesbury Road
and Hainsworth Street
Locked Bag 4001
Westmead NSW 2145

Country

Australia

Phone

(02) 9845 0761

Fax

[email protected]

No information has been provided regarding IPD availability

What supporting documents are/will be available?

No Supporting Document Provided

Results publications and other study-related documents

Documents added manually

No documents have been uploaded by study researchers.

Documents added automatically

No additional documents have been identified.

Trial Review

Documents added manually

Documents added automatically