Artery Research

Volume 8, Issue 4, December 2014, Pages 164 - 164

OR-03 CARDIO-RESPIRATORY INTERACTIONS IMMEDIATELY FOLLOWING DYNAMIC LEG CYCLING: INFLUENCES OF THE MUSCLE PUMP

Authors
Daniel W. White, Gilbert Moralez, Victoria L. Kay, Wendy L. Eubank, Peter B. Raven
The University of North Texas Health Science Center at Fort Worth, Fort Worth, TX, USA
Available Online 4 November 2014.
DOI
10.1016/j.artres.2014.09.003How to use a DOI?
Open Access
This is an open access article distributed under the CC BY-NC license.

Changes in cardiorespiratory coupling during the moments immediately following prolonged exercise are not well understood and the mode of recovery during the transition to post-exercise may be important. Cardiorespiratory coupling influences the stresses put on the arterial system by oscillatory changes in cardiac output and systemic vascular resistance. We hypothesized that the cessation of muscle pump activity and the unloading of the cardiopulmonary baroreceptors during inactive recovery would allow for exacerbated oscillations in neutrally-mediated cardiovascular function and arterial control resulting in an unstable cardiorespiratory environment. To test this hypothesis, healthy subjects (n = 13, 3 female) performed 40 minutes high intensity two-legged cycling exercise followed by active and inactive recovery. Electrocardiogram (HR), beat-to-beat blood pressure (BP), thoracic impedance (Z0), respiratory frequency and muscle sympathetic nerve activity (MSNA) were continuously monitored throughout the protocol. Data analysis was performed in the minute prior to cessation of pedaling and the first minute of inactive recovery. Z0 was significantly higher during inactive vs. active recovery (57.1 vs. 55.8 units, P = 0.02; Fig. A). Respiratory coupling to HR, BP and MSNA was confirmed by signal coherence analysis (0.98, 0.98 and 0.86, respectively). Spontaneous baroreflex sensitivity was significantly increased during inactive recovery for the Up-Up reflex (2.58 fold, P < 0.05; Fig. B) and tended to be increased for the Down-Down reflex (1.53 fold, P = 10; Fig. B). We conclude that the magnitude of respiratory-induced oscillations in BP, HR, and MSNA during recovery from exercise is dependent on muscle pump induced changes in central blood volume. Greater cardiovascular sensitivity during inactive recovery may place a larger strain on the arterial system and may partially explain increased risk of sudden death following acute exercise.

Journal
Artery Research
Volume-Issue
8 - 4
Pages
164 - 164
Publication Date
2014/11/04
ISSN (Online)
1876-4401
ISSN (Print)
1872-9312
DOI
10.1016/j.artres.2014.09.003How to use a DOI?
Open Access
This is an open access article distributed under the CC BY-NC license.

Cite this article

TY  - JOUR
AU  - Daniel W. White
AU  - Gilbert Moralez
AU  - Victoria L. Kay
AU  - Wendy L. Eubank
AU  - Peter B. Raven
PY  - 2014
DA  - 2014/11/04
TI  - OR-03 CARDIO-RESPIRATORY INTERACTIONS IMMEDIATELY FOLLOWING DYNAMIC LEG CYCLING: INFLUENCES OF THE MUSCLE PUMP
JO  - Artery Research
SP  - 164
EP  - 164
VL  - 8
IS  - 4
SN  - 1876-4401
UR  - https://doi.org/10.1016/j.artres.2014.09.003
DO  - 10.1016/j.artres.2014.09.003
ID  - White2014
ER  -