A high-salt meal does not augment blood pressure responses during maximal exercise

Area of Science:

• Cardiovascular Physiology
• Exercise Science
• Nutrition Science

Background:

• Augmented blood pressure responses during exercise predict future cardiovascular disease.
• High dietary sodium intake is known to increase blood pressure during static exercise.
• The effect of high sodium intake on blood pressure during dynamic exercise is not well understood.

Purpose of the Study:

• To investigate if an acute high-sodium meal augments blood pressure responses during dynamic exercise.
• To test the hypothesis that a high-sodium meal would increase blood pressure during maximal dynamic exercise.

Main Methods:

• Twenty healthy adults consumed either a high-sodium meal or a low-sodium meal in a randomized, crossover design.
• Blood pressure, heart rate, cardiac output, and total peripheral resistance were measured at rest and during a graded maximal exercise test on a cycle ergometer.
• Serum sodium and plasma osmolality were measured post-meal.

Main Results:

• The high-sodium meal significantly increased serum sodium and plasma osmolality compared to the low-sodium meal.
• There was no significant difference in systolic or diastolic blood pressure during peak dynamic exercise between the high-sodium and low-sodium meal conditions.
• Cardiac output and total peripheral resistance also did not differ significantly between conditions during exercise.

Conclusions:

• An acute high-sodium meal does not appear to augment blood pressure responses during dynamic exercise in healthy adults.
• Despite physiological changes in serum sodium and osmolality, acute high sodium intake does not exacerbate exercise-induced blood pressure surges.
• These findings suggest that acute dietary sodium may not be a primary driver of augmented blood pressure responses during dynamic exercise, a known cardiovascular disease risk factor.