Effect of severe exercise on plasma catecholamines in differently trained athletes.

OBJECTIVE: In the present study we investigated whether plasma catecholamine (CA) responses to short-term severe exercise (SX) are affected by different training regimen and whether this test will increase plasma catecholamine sulfates.
METHODS: Nine anaerobically (ANTA) and eight aerobically trained male athletes (ATA) performed a severe treadmill exercise test (SX) at similar oxygen demands, leading to exhaustion within 2-3 min.
RESULTS: The anaerobic contribution to energy supply was higher in ANTA than in ATA as indicated by the higher maximal accumulated oxygen deficit (37.5+/-3.5 vs. 22.7+/-4.4 mL x kg(-1) x min(-1)) (means +/- SE) (P<0.009) and blood lactate concentration after exercise (19.4+/-2.4 vs. 15.0+/-1.9 mmol x L(-1)) (P<0.005). In both groups plasma norepinephrine (NE), norepinephrine sulfate (NE-S), epinephrine (EPI), and epinephrine sulfate (EPI-S) increased significantly (P<0.05) during exercise with higher increments (P<0.05) in ANTA than in ATA (NE: 87.5+/-9.7 vs. 60.8+/-7.1 nmol x L(-1), P<0.034; EPI: 16.6+/-3.3 vs. 6.9+/-1.2 nmol x L(-1), P<0.009).
CONCLUSION: Data suggest that during this type of exercise the sympathoadrenergic system is more activated in ANTA than in ATA and seems related to the higher anaerobic contribution to energy supply in ANTA. The short duration of SX was sufficient to increase plasma NE-S and EPI-S concentration.