Sprint Snacks: The Effects of Prolonged Rest on Reduced Exertion Interval Training.

Exercise Sprint Snacks: The Effects of Prolonged Rest, Reduced Exertion High-intensity Interval Training (PR-REHIIT) Compared to Standard Reduced Exertion High-intensity Interval Training (REHIIT).

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.

Study Overview

• Status: Completed
• Conditions: Cardiorespiratory Fitness
• Intervention / Treatment: Other: PR-REHIIT; Other: REHIIT

• Study Type: Interventional
• Enrollment (Actual): 33
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • British Columbia
    • Kelowna, British Columbia, Canada, V1V 1V7
      • University of British Columbia

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 35 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

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

Exclusion Criteria:

• 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.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: PR- REHIIT; 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; 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.
Experimental: REHIIT; 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; 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.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in VO2max	Maximal oxygen uptake assessed using a ramp increase protocol on a cycle ergometer.	Before and after the 6 week intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in 10 km Time Trial Performance	Time to complete a simulated 10 km Time Trial on a Cycle ergometer	Before and after the 6 week intervention

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Exercise Enjoyment Scale	This outcome will measure the enjoyment from either PR-REHIIT or REHIIT exercise intervention	6 weeks
Intention Questionnaire	This outcome will measure the likelihood of an individual incorporating either PR-REHIIT or REHIIT into their exercise routine.	6 weeks

Collaborators and Investigators

• Sponsor: University of British Columbia

Study record dates

Study Major Dates

• Study Start (Actual): May 30, 2017
• Primary Completion (Actual): November 1, 2017
• Study Completion (Actual): November 1, 2017

Study Registration Dates

• First Submitted: May 17, 2017
• First Submitted That Met QC Criteria: May 18, 2017
• First Posted (Actual): May 19, 2017

Study Record Updates

• Last Update Posted (Actual): November 7, 2018
• Last Update Submitted That Met QC Criteria: November 5, 2018
• Last Verified: November 1, 2018

More Information

Terms related to this study

• Keywords: VO2max, maximal oxygen uptake
• Other Study ID Numbers: H17-00641

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Undecided
• IPD Plan Description: Individual data will be shown in all manuscript figures

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No