What happens to stroke volume during the concentric phase of resistance training?

During the concentric phase of resistance training, stroke volume typically does not show significant changes compared to resting levels. This phase involves muscle contraction where the heart is working to pump blood against the pressure created by the constricting muscles. Blood flow can be temporarily diverted from non-working muscle groups, and increased intrathoracic pressure during the lift may compress the heart and inhibit its ability to fill adequately during the diastolic phase.

Consequently, while there may be slight variations in stroke volume due to the demands of the exercise, it is generally considered to remain stable in comparison to resting levels. This stability is important for maintaining adequate blood circulation during the exercise session.

In contrast, stroke volume could be expected to increase or decrease under different conditions, such as during aerobic exercises or if there's a significant increase in intensity or fatigue, which isn't the focus of the concentric phase. Understanding this concept is critical for evaluating cardiovascular responses to different exercise modalities.