Acute High Intensity Interval Training and Blood Flow Restriction

Not Applicable

Completed

• Conditions: Activity, Motor

• Registration Number: NCT05835544
• Lead Sponsor: Nanyang Technological University

Brief Summary

The study aims to look at the blood flow restriction (BFR) + high intensity interval training (HIIT) variables to induce an optimal acute training stimulus (i.e., acute responses in main outcome measures of muscular activation, muscular deoxygenation, and secondary outcome measures of heart rate (HR), blood lactate (bLa), subjective ratings of perceived exertion and discomfort)

The hypotheses for this study are: (i) BFR increases muscular deoxygenation, muscular activation when HIIT exercise is of the same intensity, (ii) however, comparing between a lower BFR + HIIT exercise intensity (e.g. 80% V̇O2max) and higher HIIT exercise intensity (e.g. 100% V̇O2max), muscular deoxygenation and activation will be similar but HR will be lower in the BFR + HIIT condition.

Detailed Description

This study revolves around the optimisation of blood flow restriction (BFR) and high-intensity interval training (HIIT) protocols for the racket sport athlete. The study aims to look at the BFR + HIIT variables to induce an optimal acute training stimulus. This can be achieved with the consideration of two main research questions: (i) What is the ideal combination of BFR cuff pressure and exercise intensity (i.e. cycling) to elicit favourable training stimuli, i.e., acute responses in main outcome measures of muscular activation, muscular deoxygenation, and secondary outcome measures of heart rate (HR), blood lactate (bLa), subjective ratings of perceived exertion and discomfort?; (ii) How does BFR + HIIT compare with traditional HIIT at a similar or higher exercise intensity in terms of these acute responses?

The hypotheses for this study are: (i) BFR increases muscular deoxygenation, muscular activation when HIIT exercise is of the same intensity, (ii) however, comparing between a lower BFR + HIIT exercise intensity (e.g. 80% V̇O2max) and higher HIIT exercise intensity (e.g. 100% V̇O2max), muscular deoxygenation and activation will be similar but HR will be lower in the BFR + HIIT condition.

Study Timeline

• Study Start: 2022-08-01
• Primary Completion: 2022-12-31
• Study Completion: 2022-12-31
• Study First Submitted: 2023-04-05
• Study First Submitted QC: 2023-04-18
• Study First Posted: 2023-04-28
• Status Verified: 2024-04
• Last Update Submitted: 2024-04-02
• Last Update Posted: 2024-04-03

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 24

Inclusion Criteria

• Male
• Age: 18-40 years
• Competed in competitive varsity sports (endurance, tennis, badminton, squash, football, basketball, etc.) at the varsity/club level
• Actively training for at least 2 sessions (1 - 1.5h) per week
• Healthy (free from illnesses) and no musculoskeletal injuries for the past 6 months
• No history of cardiometabolic, vascular diseases or similar conditions (high blood pressure, peripheral vascular diseases, heart diseases, metabolic syndrome, diabetes, stroke, etc.).
• Pass pre-participation health screening tests - Physical Activity Readiness Questionnaire for Everyone (PAR-Q+) and Australian Institute of Sport (AIS) Blood Flow Restriction (BFR) pre-screening questionnaire (no history of any risk factors).
• Maximal oxygen uptake (VO2max) of ≥40mmol/min/kg during a maximal aerobic cycling test.
• Non-smoker
• Drink alcohol less than 3 times each week and less than 3 drinks each time

Exclusion Criteria

• Any diagnosed form of cardiometabolic disease (CVD, diabetes, metabolic syndrome, hypertension)
• Any symptoms contraindication of exercise testing (eg chest pains)
• Any balance or dizziness problems
• Any chronic medical conditions (whether medicated or not)
• Any bone joint problems
• Any Physician diagnosed contraindications to exercise

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Primary Outcome Measures

Name	Time	Method
Heart rate	Measured and compared between each acute arm (condition)	Heart rate using short-range telemetry
Blood lactate concentration	Measured and compared between each acute arm (condition)	Fingertip capillary measure
Muscle oxygenation	Measured and compared between each acute arm (condition)	Near infra-red spectroscopy to examine regional tissue (the vastus lateralis muscle) oxygenation i.e, the percentage of haemoglobin and deoxyhaemoglobin (physiological parameter)
Muscle activation	Measured and compared between each acute arm (condition)	Surface electromyography of the vastus lateralis and biceps femoris muscles to determine electrical activity of the motor units (physiological parameter)

Secondary Outcome Measures

Name	Time	Method
Rating of perceived exertion	Measured and compared between each acute arm (condition)	Borg Rating of Perceived Exertion scale 6-20 (6 = no exertion at all; 20 = maximal exertion)
Exertion and Pain scale	Measured and compared between each acute arm (condition)	Borg Category-Ratio (CR) 10 scale (0 = No exertion at all; 10 = Maximal)

Trial Locations

Locations (1)

Human Bioenergetics Laboratory, National Institute of Education, Nanyang Technological University; 🇸🇬 Singapore, Singapore