1. The Discrepancy Between External and Internal Load/Intensity during Blood Flow Restriction Exercise: Understanding Blood Flow Restriction Pressure as Modulating Factor.
- Author
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Bielitzki, Robert, Behrens, Martin, Behrendt, Tom, Franz, Alexander, Centner, Christoph, Hughes, Luke, Patterson, Stephen D., Owens, Johnny, Behringer, Michael, and Schega, Lutz
- Subjects
MYALGIA ,MUSCLE fatigue ,EXERCISE intensity ,RESISTANCE training ,MUSCLE strength ,BLOOD flow restriction training ,CONCEPTUAL structures - Abstract
Physical exercise induces acute psychophysiological responses leading to chronic adaptations when the exercise stimulus is applied repeatedly, at sufficient time periods, and with appropriate magnitude. To maximize long-term training adaptations, it is crucial to control and manipulate the external load and the resulting psychophysiological strain. Therefore, scientists have developed a theoretical framework that distinguishes between the physical work performed during exercise (i.e., external load/intensity) and indicators of the body's psychophysiological response (i.e., internal load/intensity). However, the application of blood flow restriction (BFR) during exercise with low external loads/intensities (e.g., ≤ 30% of the one-repetition-maximum, ≤ 50% of maximum oxygen uptake) can induce physiological and perceptual responses, which are commonly associated with high external loads/intensities. This current opinion aimed to emphasize the mismatch between external and internal load/intensity when BFR is applied during exercise. In this regard, there is evidence that BFR can be used to manipulate both external load/intensity (by reducing total work when exercise is performed to exhaustion) and internal load/intensity (by leading to higher physiological and perceptual responses compared to exercise performed with the same external load/intensity without BFR). Furthermore, it is proposed to consider BFR as an additional exercise determinant, given that the amount of BFR pressure can determine not only the internal but also external load/intensity. Finally, terminological recommendations for the use of the proposed terms in the scientific context and for practitioners are given, which should be considered when designing, reporting, discussing, and presenting BFR studies, exercise, and/or training programs. Key Points: The application of BFR during exercise with low external load/intensity can lead to internal responses that are commonly associated with high external load/intensity resulting in a discrepancy between the characteristics of exercise and the acute psychophysiological responses. The BFR pressure can be adjusted to increase the internal load/intensity (i.e., elevating physiological and perceptual responses) to intensify the exercise stimulus or to decrease the external load/intensity (e.g., reducing the number of repetitions when exercise is performed to exhaustion), which is of particular importance during musculoskeletal rehabilitation when high or cumulative low mechanical stress might be contraindicated. We encourage researchers to adapt their wording in the BFR literature accordingly, given that the extent of internal load/intensity during BFR exercise is determined by the interaction of several external exercise variables (e.g., external resistance, number of repetitions/cycles, cuff pressure) to specify the generated exercise stimulus (e.g., "low external load BFR walking", "low external load BFR resistance exercise"). [ABSTRACT FROM AUTHOR]
- Published
- 2024
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