VO2 Max: In Vivo Model for Functional Red Cell Testing. Can RECESS be Explained?

Inclusion Criteria:

• Habitual exerciser defined as ≥ 30 minutes of at least moderate or high intensity exercise ≥ 3 times per week. After consent, and at the subsequent screening visit, a VO2 max test will be performed, and subjects with a low value (< 35 mL/kg/min) will be excluded (screen failure). Based on our previous experience, we anticipate that <10% of the subjects will fall into this category

• Calculated total blood volume (TBV) ≥4,500 mL using an established formula:

  1. Men: (0.006012 x H3) + (14.6 x W) + 604 = TBV
  2. Women: (0.005835 x H3) + (15 x W) + 183 = TBV [H=height in inches; W=weight in pounds]
• Has access to transportation to visit the blood collection facility and to return to Stony Brook for all study visits.

Exclusion Criteria:

• Any significant acute or chronic medical illness or problem, including, but not limited to, diabetes, hypertension, cardiac disease, asthma, chronic obstructive lung disease
• Current or recent (last 60 days) tobacco or nicotine use
• History of sickle cell trait or disease or any other acquired or hereditary hematological abnormality
• History of fainting or other significant adverse reaction during phlebotomy or donation of blood
• Known prolonged corrected QT interval (or evidence of such at screening) on electrocardiogram defined as >470 ms
• Known or suspected illicit drug or alcohol abuse
• Known or suspected HIV, Hepatitis B, or Hepatitis C infection
• History of thrombophilia or anticoagulant therapy
• Pregnancy
• Obesity defined as BMI>30
• Recent history of blood donation: a) Single whole blood unit donation within the past 8 weeks; b) Double RBC donation by apheresis within the past 16 weeks; or c) Plasma donation by apheresis within the past 4 weeks
• Inadequate RBC mass based on TBV <4500 ml (above) or screening Hb <14 g/dL