Adequacy of Muscle Blood Flow During Handgrip Exercise
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University of Toledo / OhioLINK
2009
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| Online Access: | http://rave.ohiolink.edu/etdc/view?acc_num=toledo1260580537 |
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ndltd-OhioLink-oai-etd.ohiolink.edu-toledo12605805372021-08-03T06:07:33Z Adequacy of Muscle Blood Flow During Handgrip Exercise Harper, Allison Jessica Anatomy and Physiology Sports Medicine exercise blood flow EMG post-exercise hyperemia <p>The purpose of this dissertation was to determine if limb blood flow was sufficient for the performance of handgrip exercise utilizing a variety of muscle contraction patterns, exercise intensities, and exercise durations. Subjects first performed heavy intensity intermittent isometric and dynamic handgrip exercise to examine the effect of muscle contraction pattern on mean blood flow and exercise tolerance. Brachial artery mean blood flow was measured throughout exercise using Doppler ultrasound. Electromyography (EMG) of the forearm muscles was also measured, and the time-tension integral was calculated to assure a similar work rate between protocols. The Time to task failure was significantly greater in intermittent isometric than dynamic exercise. However, there were no differences in mean blood flow following the first minute of exercise or in the normalized iEMG/time-tension integral ratio. These results indicate that motor unit recruitment patterns, mean blood flow and presumably oxygen delivery to the working muscles were similar between conditions, and therefore may not be a primary determinant of exercise tolerance during handgrip exercise.</p><p>Compared to the mean blood flow response during dynamic handgrip exercise, there is a transient overshoot in muscle blood flow early in recovery which has been used as evidence to suggest that blood flow is inadequate for the metabolic requirements of the exercise. If muscle blood flow is limited during handgrip exercise, one might reason that progressive increases in exercise duration would lead to greater increases in post-exercise blood flow, consistent with the results of post-occlusive studies. In a subsequent study, subjects performed four bouts each moderate and heavy intensity dynamic handgrip exercise to examine the effect of progressively increasing exercise duration on exercise and recovery blood flow responses. Brachial artery blood flow was measured during exercise and 5 min of recovery using Doppler ultrasound. Peak blood flow was calculated for both end-exercise and early recovery periods. The area under the recovery blood flow curve (5 min) was determined and used as an index of total post-exercise hyperemia. Within each exercise intensity, peak blood flow during exercise exceeded peak recovery blood flow but was independent of exercise duration. Similarly, the area under the recovery curve was greater for heavy than moderate exercise but was not associated with exercise duration. These observations suggest that the transient overshoot in blood flow during early recovery does not reflect a blood flow limitation during exercise. Therefore, neither protocol provided evidence that brachial artery blood flow was inadequate to meet metabolic requirements.</p> 2009 English text University of Toledo / OhioLINK http://rave.ohiolink.edu/etdc/view?acc_num=toledo1260580537 http://rave.ohiolink.edu/etdc/view?acc_num=toledo1260580537 unrestricted This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws. |
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NDLTD |
| language |
English |
| sources |
NDLTD |
| topic |
Anatomy and Physiology Sports Medicine exercise blood flow EMG post-exercise hyperemia |
| spellingShingle |
Anatomy and Physiology Sports Medicine exercise blood flow EMG post-exercise hyperemia Harper, Allison Jessica Adequacy of Muscle Blood Flow During Handgrip Exercise |
| author |
Harper, Allison Jessica |
| author_facet |
Harper, Allison Jessica |
| author_sort |
Harper, Allison Jessica |
| title |
Adequacy of Muscle Blood Flow During Handgrip Exercise |
| title_short |
Adequacy of Muscle Blood Flow During Handgrip Exercise |
| title_full |
Adequacy of Muscle Blood Flow During Handgrip Exercise |
| title_fullStr |
Adequacy of Muscle Blood Flow During Handgrip Exercise |
| title_full_unstemmed |
Adequacy of Muscle Blood Flow During Handgrip Exercise |
| title_sort |
adequacy of muscle blood flow during handgrip exercise |
| publisher |
University of Toledo / OhioLINK |
| publishDate |
2009 |
| url |
http://rave.ohiolink.edu/etdc/view?acc_num=toledo1260580537 |
| work_keys_str_mv |
AT harperallisonjessica adequacyofmusclebloodflowduringhandgripexercise |
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