Low-Intensity BFR Cycling: Impact on VO₂Max and Muscle Adaptations

Summary

This study aims to investigate the effects of low-intensity cycling exercise combined with blood flow restriction (BFR) on maximal oxygen consumption (VO₂max), muscle strength, and muscle thickness in sedentary adult males. Participants will be randomly assigned to three groups: (1) a cycling exercise group performing 40 minutes of cycling at 40% VO₂max, (2) a cycling with blood flow restriction group performing 15 minutes of cycling at 40% VO₂max with limb occlusion pressure at 60-80%, and (3) a control group following a shorter cycling protocol. Muscle thickness, isokinetic knee strength, and VO₂max will be measured before and after the 9-week intervention. The study is designed to evaluate whether short-duration, low-intensity cycling with BFR can induce physiological adaptations comparable to traditional longer-duration cycling protocols.

Conditions

• Aerobic Capacity
• Blood Flow Restriction (BFR) Training Effects
• Blood Flow Restriction Exercise
• Muscle Strengh
• Isokinetic
• VO2max

Interventions

PROCEDURE

Cycling with Blood Flow Restriction (15 min at 40% VO₂max with 60-80% LOP)

This intervention involves low-intensity cycling exercise at 40% of VO₂max performed on an electronically braked Astrand cycle ergometer for 15 minutes per session. During each session, pneumatic cuffs (10 cm wide, manually adjustable) are applied to the upper thighs to restrict blood flow. Individualized limb occlusion pressure (LOP) is determined via Doppler ultrasound and set progressively at 60% (weeks 1-4), 70% (weeks 5-7), and 80% (weeks 8-9). Sessions are conducted three times per week over a 9-week period. The aim is to simulate the physiological effects of high-intensity training using a low-intensity protocol.

PROCEDURE

Cycling Exercise (40 min at 40% VO₂max)

This intervention involves standard low-intensity cycling exercise at 40% of the participant's VO₂max, performed for 40 minutes per session on an electronically braked Astrand cycle ergometer. Sessions are conducted three times per week for a total duration of 9 weeks. This group does not receive any blood flow restriction or external loading. The aim is to observe the effects of traditional low-intensity, long-duration aerobic exercise on VO₂max, muscle strength, and muscle thickness.

PROCEDURE

Short-Duration Cycling Control (15 min at 40% VO₂max)

This intervention involves low-intensity cycling exercise at 40% of VO₂max performed for 15 minutes per session, using an electronically braked Astrand cycle ergometer. Participants exercise three times per week for 9 weeks. No blood flow restriction is applied. The aim of this control condition is to match the duration of the BFR intervention while omitting the occlusion component, to isolate the effect of BFR.

Sponsors & Collaborators

• Kahramanmaras Sutcu Imam University

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

SINGLE

Model

CROSSOVER

Eligibility

Min Age

18 Years

Max Age

24 Years

Sex

MALE

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2023-12-01

Primary Completion

2024-03-05

Completion

2024-03-05

Countries

• Turkey (Türkiye)

Study Locations