NCT03159949

Brief Summary

An adapted sprint interval training protocol involving 2-3 repeated 20-second sprints separated by 2-3 minutes rest (termed reduced exertion high- intensity interval training (REHIIT)) has been developed and has been shown to promote fitness benefits. This data shows how little exercise one may need to improve cardiorespiratory fitness, provided they are willing to work very hard. However, it is unknown whether the benefits of REHIIT are because of the "all-out" nature of the sprint efforts themselves or the pattern of completing sprints with relatively short (i.e., minutes) rest periods within a workout session. We are inquiring whether performing the same number and style of sprints with prolonged rest (i.e., 1-4 hours of rest in between sprints) is equally effective for improving aerobic fitness when compared to more traditional sprint interval training with 2-3 minutes of rest between sprints. Such information may make the effectiveness of sprint training more accessible and approachable for individuals unwilling or unable to plan a purposeful REHIIT exercise session into their day. If the rest interval could be prolonged then it may be possible to perform a few sprints as "exercise snacks" throughout the day without the need for a structured interval training session.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
33

participants targeted

Target at P25-P50 for not_applicable

Timeline
Completed

Started May 2017

Shorter than P25 for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

May 17, 2017

Completed
2 days until next milestone

First Posted

Study publicly available on registry

May 19, 2017

Completed
11 days until next milestone

Study Start

First participant enrolled

May 30, 2017

Completed
5 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

November 1, 2017

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

November 1, 2017

Completed
Last Updated

November 7, 2018

Status Verified

November 1, 2018

Enrollment Period

5 months

First QC Date

May 17, 2017

Last Update Submit

November 5, 2018

Conditions

Keywords

VO2max, maximal oxygen uptake

Outcome Measures

Primary Outcomes (1)

  • Change in VO2max

    Maximal oxygen uptake assessed using a ramp increase protocol on a cycle ergometer.

    Before and after the 6 week intervention

Secondary Outcomes (1)

  • Change in 10 km Time Trial Performance

    Before and after the 6 week intervention

Other Outcomes (2)

  • Exercise Enjoyment Scale

    6 weeks

  • Intention Questionnaire

    6 weeks

Study Arms (2)

PR- REHIIT

EXPERIMENTAL

PR-REHIIT participants ("Sprint Snacks") will participate in 3 separate training session per day on 3 days per week (i.e., 9 sessions per week). Each session lasts 3 minutes and 20 seconds and consists of a two-minute warm-up, a 20-second "all-out" sprint, and a one-minute cool-down. There will be 1-4 hours of rest in between training sessions where participants are free to leave the lab and go about their normal day.

Other: PR-REHIIT

REHIIT

EXPERIMENTAL

REHIIT participants will come into the lab one time per training days (3 training days per week), each session lasting 10 minutes. Training sessions involve a two-minute warm-up, 3 X 20-second sprints with three minutes rest in between, and a one-minute cool-down.

Other: REHIIT

Interventions

REHIITOTHER

REHIIT participants will come into the lab one time per training days (3 training days per week), each session lasting 10 minutes. Training sessions involve a two-minute warm-up, 3 X 20-second cycling sprints on an exercise bike with three minutes rest in between, and a one-minute cool-down.

REHIIT

PR-REHIIT participants will come into the lab on 3 separate occasions on the training days, which occur 3 days per week (i.e., 9 sessions per week). Each session lasts 3 minutes and 20 seconds and consists of a two-minute warm-up, a 20-second "all-out" sprint on a cycle ergometer, and a one-minute cool-down. There will be 1-4 hours of rest in between training sessions where participants are free to leave the lab and go about their normal day.

PR- REHIIT

Eligibility Criteria

Age18 Years - 35 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • Physically inactive (2 or less bouts of purposeful exercise per week)

You may not qualify if:

  • If your doctor has informed you that you have a heart condition and should only do physical activity recommended by a doctor.
  • If you feel pain in your chest when you perform any physical activity.
  • If in the past the month you have had chest pain when you were not doing any physical activity.
  • If you lose your balance or consciousness because of dizziness.
  • If you have bone or joint problem (for example, back, knee, or hip) that could be made worse by a change in your physical activity.
  • If you are currently pregnant or planning on becoming pregnant in the next 6 weeks.
  • You have previously had a heart attack or stroke
  • You are currently engaging in high-intensity interval training.
  • You are currently physically active (engaging in 3 or more bouts of purposeful exercise per week; a "bout" is defined as structured, planned exercise lasting at least 30 minutes)
  • You have severe chest pain or blood pressure over 240/140 during baseline testing.
  • You have exercise induced asthma or a history of syncope.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University of British Columbia

Kelowna, British Columbia, V1V 1V7, Canada

Location

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
NONE
Masking Details
Participants will know what exercise group they are assigned to.
Purpose
PREVENTION
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Assistant Professor

Study Record Dates

First Submitted

May 17, 2017

First Posted

May 19, 2017

Study Start

May 30, 2017

Primary Completion

November 1, 2017

Study Completion

November 1, 2017

Last Updated

November 7, 2018

Record last verified: 2018-11

Locations