Exercise significantly increases plasma adrenaline and oxidized low-density lipoprotein in normal healthy subjects but not in persons with spinal cord injury.

ABSTRACT

OBJECTIVES: To compare plasma concentrations of oxidized low-density lipoprotein (oxLDL) and adrenaline during exercise between persons with spinal cord injury (SCI) and able-bodied (AB) individuals. DESIGN: Randomized controlled study. SETTING: Human laboratory at a medical university. PARTICIPANTS: Persons with SCI (n=7) and AB individuals (n=9). INTERVENTION Two-hour arm crank ergometer exercise at 60% maximum oxygen consumption. MAIN OUTCOME MEASURES: Plasma oxLDL and adrenaline levels. RESULTS: Exercise significantly increased plasma adrenaline levels in AB persons (mean ± SD rest, 45.4±32.2 pg/mL; exercise, 200.9±113.7 pg/mL; P<.05) and persons with SCI; however; the magnitude of the increase in those with SCI was attenuated (mean ± SD rest, 45.4±14.0 pg/mL; exercise, 83.0±55.8 pg/mL; P<.05). Exercise also significantly increased plasma oxLDL levels in AB persons (mean ± SD rest, 102.2±30.2 U/L; exercise, 179.7±60.0 U/L; P<.05), but not in persons with SCI (mean ± SD rest, 124.3±66.0 U/L; exercise, 138.9±59.5 U/L). CONCLUSIONS: The results suggest that increases in plasma adrenaline levels during exercise contribute to the increase in plasma oxLDL levels.