The Effect of Remote Preconditioning on the Exercise Performance of the Elite Swimmers

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Andrew Redington, The Hospital for Sick Children
ClinicalTrials.gov Identifier:
NCT00761566
First received: September 26, 2008
Last updated: August 14, 2013
Last verified: August 2013
  Purpose

In this study, we will test the hypothesis that preconditioning highly trained swimmers using skeletal muscle ischemia as the stimulus will improve exercise performance assessment.


Condition Intervention Phase
Healthy
Other: Real preconditioning followed by Sham preconditioning
Other: Sham preconditioning followed by Real preconditioning
Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Investigator)
Official Title: Double Blind Randomized Controlled Trial of the Effect of Remote Preconditioning on the Exercise Performance of the Elite Swimmers

Resource links provided by NLM:


Further study details as provided by The Hospital for Sick Children:

Primary Outcome Measures:
  • Improvement in the peak velocity in the preconditioning subjects. [ Time Frame: 2 weeks ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Breathing frequency. [ Time Frame: 2 weeks ] [ Designated as safety issue: No ]
  • Blood lactate. [ Time Frame: 2 weeks ] [ Designated as safety issue: No ]
  • Improvement in critical speed. [ Time Frame: 2 weeks ] [ Designated as safety issue: No ]

Estimated Enrollment: 24
Study Start Date: October 2008
Study Completion Date: February 2010
Primary Completion Date: February 2010 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: 1 Other: Real preconditioning followed by Sham preconditioning
Subjects in this arm of the study will first receive four 5 minute cycles of upper limb ischemia interspaced with 5 minutes of reperfusion by using a blood-pressure cuff inflated to a pressure of 15 mmHg greater than systolic arterial pressure. The subjects will then cross-over to the other arm of the study and receive four 5 minute cycles of upper limb ischemia interspaced with 5 minutes of reperfusion by using a sham procedure consisting of inflating the blood pressure cuff to 10 mmHg.
Experimental: 2 Other: Sham preconditioning followed by Real preconditioning
Subjects in this arm of the study will first receive four 5 minute cycles of upper limb ischemia interspaced with 5 minutes of reperfusion by using a sham procedure consisting of inflating the blood pressure cuff to 10 mmHg. They will then cross-over to the other arm of the study and receive four 5 minute cycles of upper limb ischemia interspaced with 5 minutes of reperfusion by using a blood-pressure cuff inflated to a pressure of 15 mmHg greater than systolic arterial pressure.

Detailed Description:

The main purpose of this study is to determine if it is possible to precondition competitive swimmers and improve their exercise performance to provide further insight into the physiological mechanisms through which preconditioning may function. With four 5 minute inflation cycles of a blood-pressure cuff, we will induce skeletal muscle ischemia which is known to be a powerful method of preconditioning. Each swimmer will be blinded to the expected effect and randomly assigned to real preconditioning versus the sham intervention which will consist of four 5 minute cycles of blood pressure cuff inflation to 10mmHg. During a subsequent training session, the subjects will receive the intervention they have not received during the previous test session. Therefore, each subject will be part of both study groups and will serve as their own control. To evaluate the exercise performance, the subjects will perform an incremental swimming test protocol based on methods developed and reported by a member our research team. Swimming velocity, blood lactate level, heart rate, breathing frequency, dyspnoea and oxygen saturation will be measured during incremental exercise. Finally, we would like to determine the preconditioning effect of regular exercise training in an animal model.

Exercise performance is thought to be limited by skeletal, cardiac and respiratory muscle fatigue associated with episodes of exercise induced arterial hypoxemia. Preconditioning is defined as a period of brief lack of oxygen or ischemia in a tissue that protects the heart or any other organ from another sustained episode of ischemia. Preconditioning is believed to improve exercise performance by protecting the skeletal, cardiac and respiratory muscles against decreased oxygen and by-products of anaerobic metabolism that may limit an individual's exercise performance. Elite athletes, such as highly trained swimmers, may provide the research team with the opportunity to evaluate the effect of preconditioning during local tissue hypoxia and anaerobic metabolic by-products in healthy adolescents, which is otherwise not possible. With this study, we will show if it is possible to precondition competitive swimmers and improve their exercise performance using ischemia of the limb as a preconditioning stimulus.

  Eligibility

Ages Eligible for Study:   13 Years to 22 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Healthy male or female athlete volunteers
  • Post-pubescent swimmers between the ages of 13 and 22 years (or healthy non-athletes (for the "equipment control" group and for the control arm for the animal model section)
  • Members of competitive swimming teams
  • Have achieved a swimming performance time within 5% of national qualification standards

Exclusion Criteria:

  • Illness, surgery, or medical intervention within the last 48 hours
  • Diabetes mellitus
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00761566

Locations
Canada, Ontario
Toronto Swim Club, University of Toronto Athletic Centre
Toronto, Ontario, Canada
Sponsors and Collaborators
The Hospital for Sick Children
Investigators
Principal Investigator: Andrew Redington, MD The Hospital for Sick Children
  More Information

No publications provided

Responsible Party: Andrew Redington, Head, Heart Centre-Cardiology Division, The Hospital for Sick Children
ClinicalTrials.gov Identifier: NCT00761566     History of Changes
Other Study ID Numbers: 1000012617
Study First Received: September 26, 2008
Last Updated: August 14, 2013
Health Authority: Canada: Ethics Review Committee

Keywords provided by The Hospital for Sick Children:
Elite swimmers
Exercise
Preconditioning

ClinicalTrials.gov processed this record on July 28, 2014