1. ALEXA BROOKS DR. SARA JARVIS NORTHERN ARIZONA UNIVERSITY Effects of hyper-hydration on orthostatic tolerance in men and women

2. Introduction Interventions  Hyper-hydration  Salt supplementation Purpose:  Determine effects of hyper- hydration with Gatorade on orthostatic intolerance Hypothesis:  Men and women will show increases in orthostatic tolerance  Relative improvements will be similar between sexes

3. Methods Subject Characteristics Men (n=8)Women (n=7) Age (years)21±4.521±0.5 Height (meters)1.8±0.1*1.7±0.1 Weight (kg)67.7±6.961.9±10.4 BMI (kg/m 2 )22.1±3.021.9±2.6 Resting SBP (mmHg)116±8.6114±9.2 Resting DBP (mmHg)69±6.9*77±5.4 Resting HR (bts/min)67±10.680±12.4 Values are mean±SD, *Significant difference between sexes

4. Methods 2 randomly assigned sessions  Euhydrated  6 days  normal food intake  Hyper-hydrated  6 days  2 L Gatorade/day Tilt Test 1 L

5. Data Collection Electrocardiogram SunTech Tango  BP from brachial artery Finometer  Beat to beat BP from finger Chest Strap  Breathing rate Tilt Test

6. Results ** † * Significant difference during HUT † Significant difference between sexes

7. Results *Significant difference during HUT † Significant difference between sexes * † * †

8. Results † Significant difference between sexes †

9. Discussion Salt supplementation  Increases:  Plasma volume  Total peripheral resistance  Orthostatic tolerance Glucose  Decrease in peripheral resistance  Insulin will cause vasodilation Things to consider:  Salt supplementation was ~6g/day for 8 weeks  Glucose ingestion was right before tilt

10. Conclusion Men were more orthostatically tolerant than women. Gatorade did not improve orthostatic intolerance.

11. Acknowledgements Subjects who participated Dr. Jarvis Personnel of NAU’s Cardiovascular Regulation Lab NAU/NASA Space Grant Internship Arizona Space Grant Consortium

12. ANY QUESTIONS? Thank you!