Cerebral Blood Flow Responses to Aquatic Treadmill Exercise

Area of Science:

• Exercise Physiology
• Cardiovascular Physiology
• Neurology

Background:

• Aquatic treadmills are utilized in rehabilitation for conditions like spinal cord injury, osteoarthritis, and stroke.
• They also aid athletes in returning to exercise training sooner.
• The impact of aquatic treadmill exercise on cerebral blood flow (CBF) remains unexamined.

Purpose of the Study:

• To investigate the effects of aquatic treadmill exercise on cerebral blood flow (CBF) and heart rate (HR).
• To test the hypothesis that aquatic treadmill exercise augments CBF and lowers HR compared to land-based treadmill exercise.

Main Methods:

• Eleven participants underwent incremental exercise protocols in a crossover design, comparing aquatic and land-based treadmills.
• Measurements included middle cerebral artery blood flow velocity (MCAv) and heart rate (HR).
• Exercise involved varying speeds and immersion depths (iliac crest, midthigh, midchest).

Main Results:

• Aquatic treadmill exercise showed a greater increase in mean MCAv (21%) compared to land exercise (12%).
• Aquatic exercise was associated with a lower overall heart rate (HR).
• Increased water immersion depth further reduced HR without significantly altering MCAv.

Conclusions:

• Aquatic treadmill exercise can enhance exercise-induced elevations in CBF.
• This suggests potential for optimizing shear stress-mediated adaptations in the cerebrovasculature.
• Aquatic exercise offers a promising alternative for individuals seeking cardiovascular and cerebrovascular benefits.