. 2017 Mar 21;11(9):1558–1566. doi: 10.1017/S1751731117000556

Table 1.

Physiological responses before, during and after an incremental exercise test in eight mature Icelandic riding horses ¹

			Incremental exercise test					Recovery
Item	At rest	Warm-up	BWR₂₀	BWR₂₅	BWR₃₀	BW₃₅	BWR_20b	5 min	15 min	30 min	24 h	48 h	RMSE
HR (b.p.m.)	36^a	145^b	187^c	191^cd	195^cd	199^d	189^c	78^e	62^f	49^a			8
Lac (mmol/l)	0.9^a	1.4^b	3.6^cde	4.1^cd	5.7^gh	7.9ⁱ	5.8^g	4.5^ch	2.9^df	2.3^ef	0.9^a	0.8^a	1.0
Hct (%)	34^a	43^bc	45^bc	45^b	46^b	45^b	44^b	42^c	38^d	36^a			2
BF (breaths/min)	15^a	38^ab	54^bcd	69^ce	88^ef	101^f	104^f	58^bce	42^ac	28^ad			19
Rectal temperature (°C)	37.5^a						39.5^b			38.5^c			0.3
CK concentration (U/l)	395^a							404^a			443^a	463^a	67
AST concentration (U/l)	368^a							386^b			379^ab	394^ab	80

BF=breathing frequency; CK=creatine kinase; AST, aspartate amino transferase.

Values presented as least square means and root mean standard error (RMSE). Samples for plasma lactate concentration (Lac), hematocrit (Hct) and breathing frequency (BF) were collected at rest, at end of warm-up, at end of five phases (each 642 m in tölt) of the exercise test, where the ratio between rider : horse BW started at 20% (BWR₂₀), was increased to 25% (BWR₂₅), 30% (BWR₃₀) and 35% (BWR₃₅), and then decreased to 20% (BWR_20b), and at end of 5, 15, 30 min recovery and 24 and 48 h recovery. Measurements of heart rate (HR) were made during the last minute of the same phases except at rest, where HR was measured at night using a 30-min period with a low HR. Means within a row with different letters are significantly different (P<0.05).