Reduced high intensity training distance had no effect on VLa4 but attenuated heart rate response in 2-3-year-old Standardbred horses

Table 4 Left ventricle- and aortic diameter, blood pressure and resting heart rate

Age	January 2 year		December 2 year		December 3 year
Group	C	R	C	R	C	R
N	8	8	8	8	8	7
LVIDd ¹	2.34 ± 0.09	2.33 ± 0.09			2.40 ± 0.09	2.28 ± 0.09
Aortic diameter ¹	1.70 ± 0.05	1.75 ± 0.05			1.75 ± 0.05	1.70 ± 0.05
RR ²	11 ± 1	12 ± 1^a	9 ± 0	9 ± 0^b	10 ± 1	11 ± 1^b
Systolic BP ³	116 ± 4	117 ± 4	116 ± 5	114 ± 5	120 ± 4	109 ± 5
Diastolic BP ³	72 ± 3	73 ± 3	64 ± 3	67 ± 3	66 ± 4	67 ± 4
Mean arterial BP ³	87 ± 3	89 ± 3	83 ± 4	84 ± 4	86 ± 4	82 ± 4
Resting HR1 ⁴	47 ± 2^A	50 ± 2^a	41 ± 2^B	41 ± 2^b	35 ± 1^B	41 ± 1^b*
Resting HR2 ⁴	39 ± 1^A	38 ± 1^a	36 ± 1^B	39 ± 1^a	36 ± 1^B	40 ± 1^a*

¹Cm/100 kg BW.
²Breaths per minute.
³mmHg.
⁴beats per minute.
*indicates a difference between groups within age (P < 0.05).
^a,ADifferent superscript letters indicates a difference (P < 0.05) within group between occasions, upper case letters = difference in C-group, lower case letters = difference in R-group.
Left ventricle inner diameter diastole (LVIDd) and aortic diameter in 16 1- and 3-year-old Standardbred horses allocated to either a control (C) or a reduced (R) (by 30% distance) training program and resting heart rate determined with phonendoscope (Resting HR1) and HR-meters (Resting HR2), respiratory rate (RR), systolic blood pressure (BP), diastolic BP and mean arterial pressure at 1, 2 and 3 years of age in the same horses (lsmeans ± SE).

ISSN: 1751-0147