Catecholamines (CAT) play an important role in modulating the response to exercise. The kinetics of CAT changes during exercise are difficult to study due to their short biological half-life. Learning about variations in plasma CAT levels during training could furnish new information regarding sweating, redistribution of blood flow and energy metabolism. Four untrained standardbred geldings aged 4-7 years, adapted to treadmill work, were used to determine the influence of training on plasma adrenaline (A) and noradrenaline (NA) kinetics. The horses underwent a standardized exercise test (SET) on treadmill before (SET1), 1 (SET2) and 2 months after (SET3) the start of a moderate training period on treadmill. The SET procedure was: warm-up and a single step of 2 min at 200 beats/min heart rate (SS). The automatic blood collection system (that has been carried out during SS) and the preparation of the horses have been described previously. The system was programmed to obtain a blood sample every 15s (8 blood samples per SS). Analyses were performed by HPLC. Training progress was monitored by means of anaerobic threshold velocity (V4) and the velocity during SS (V200) before and after the 2-month training. Wilcoxon’s test was used for statistical analysis. V4 (m/s mean±SD) changed from 7.3±1.3 to 8.8±1 and V200 from 8.4±1.3 to 10.3±1.3 after training period. Results showed decreased levels of A and NA with significant differences between SET1/SET2 and SET1/SET3 for A (p=0.007) and NA (p=0.007). There were no differences between SET2 and SET3 for A (p=0.195) and NA (p=0.054). These preliminary data seem to indicate that training influences the level of plasma CAT and that this influence is greater during the first training period in untrained standardbreds.
|Autori:||P. BARAGLI; DUCCI M; D. GATTA; A. GAZZANO; C. SIGHIERI|
|Titolo:||Influence of training on plasma adrenaline and noradrenaline kinetics in untrained Standardbreds|
|Anno del prodotto:||2006|
|Digital Object Identifier (DOI):||10.1111/j.2042-3306.2006.tb05549.x|
|Appare nelle tipologie:||1.1 Articolo in rivista|