Acute physiological and perceptual responses to three blood flow restricted interval exercise protocols: a randomised...

Area of Science:

• Exercise Physiology
• Sports Science
• Biomedical Engineering

Background:

• Blood flow restriction (BFR) is a technique used to augment the training stimulus during exercise.
• Understanding the acute physiological and perceptual responses to BFR combined with interval exercise is crucial for optimizing training protocols.

Purpose of the Study:

• To investigate the acute physiological and perceptual responses to three different lower-limb BFR combined with interval exercise protocols.
• To compare the effects of BFR applied during rest versus during exercise at varying intensities and occlusion pressures.

Main Methods:

• Twenty-four male athletes completed four randomized crossover conditions: high-intensity control (HI), high-intensity recovery occlusion (HIRO), moderate-intensity low occlusion (MILO), and moderate-intensity high occlusion (MIHO).
• Exercise protocols involved three sets of five 30-second cycling intervals with 30-second active recovery, interspersed with 3-minute seated rest.
• Physiological measures included tissue saturation index, deoxyhemoglobin, oxyhemoglobin, total hemoglobin, heart rate, blood lactate, and vastus lateralis muscle activity. Perceptual responses (pain, exertion) were also recorded.

Main Results:

• HIRO demonstrated lower tissue saturation index and higher deoxyhemoglobin, oxyhemoglobin, and total hemoglobin during recovery compared to other conditions.
• HIRO resulted in significantly higher heart rate from the second set and elevated blood lactate post-exercise.
• MIHO induced greater muscle deoxygenation and lower muscle activation during exercise, alongside higher perceived pain and exertion than other conditions.

Conclusions:

• Applying BFR during the rest intervals of high-intensity exercise increases physiological stress without impacting exercise intensity or perceptual load.
• Incorporating BFR during moderate-intensity exercise can heighten both physiological and perceptual responses, potentially exceeding those of high-intensity exercise without BFR.
• These findings suggest that the timing and intensity of BFR application significantly modulate the acute training response during interval exercise.