Abstract:
The aim of this study was to determine whether three acupuncture treatments affected thoroughbred racehorses in training. Heart rate variability (HRV) at rest and stride parameters (SP) during a 600m gallop were measured. Needles were inserted for 20 minutes into pre-selected acupuncture points in the treatment horses while those in the non-treatment group were haltered.
The delta values (post-treatment minus pre-treatment) of the groups were compared. There were no significant changes (p < 0.05) in the HRV indicators. The treatment group showed (delta median of treatment vs. non-treatment group) that the parasympathetic (PNS) indicators shifted towards inhibition of the vagal system (RMSSD = - 2.19 vs. 1.47; HF = - 37.19 vs. 19.42; SD1 = - 1.56 vs. 1.04). The delta medians of indicators associated with the combined effect of the PNS and sympathetic nervous system (SDNN = 4.39 vs. - 4.00; LF = 179.48 vs. - 397.26; SD2 = 8.55 vs. - 7.48); cardiac autonomic balance (LF/HF = 0.26 vs. - 0.32; LF norm = 14.23 vs. - 0.80; HF norm = - 4.78 vs. 3.54) and heart rate measures (Mean HR = 3.96 vs. - 3.00; Mean RR = - 169.72 vs. 107.54) showed a shift in opposite directions.
The SP results showed a significant increase in maximum stride count (p = 0.004). The delta medians showed a shift in opposite directions i.e., average stride length (-0.06 vs. 0.05), average stride count (0.31 vs. -0.26), maximum stride count (0.84 vs. -5.70), maximum speed (1.30 vs. -0.80) and stride length at maximum speed (0.13 vs. -0.01).
Thus, the non-treatment group seemed to perform better and were calmer, suggesting that a withdrawal period may be appropriate following acupuncture treatments.