Heart rate and heart rate variability responses during three exercise tests and recovery in horses participating in the Fédération Équestre Internationale Eventing World Challenge

Figures

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  Fig. 1. RR interval (A), mean HR (B), and peak HR (C) in response to the three exercise tests and recoveries in the Eventing World Challenge. ⋇ indicates a significant difference from the baseline before the competition (control). # and λ indicate significant differences between comparison pairs. HR: heart rate; RR: beat-to-beat; W-D, W-J, and W-CC: warm-up before dressage, jumping, and cross-country tests, respectively; D, J, and CC: dressage, jumping, and cross-country tests, respectively; 30-D to 90-D: 30–90 min after the dressage test; 30-J to 240-J and 30-CC to 240-CC: 30–240 min after the jumping and cross-country tests, respectively

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  Fig. 2. SDNN (A), RMSSD (B), and stress index (C) in response to the three exercise tests and recoveries in the Eventing World Challenge. ⋇ indicates a significant difference from the baseline before the competition (control). # and λ indicate significant differences between comparison pairs. RR: beat-to-beat; SDNN: standard deviation of normal-to-normal RR intervals; RMSSD: root mean square of successive RR interval differences; W-D, W-J, and W-CC: warm-up before dressage, jumping, and cross-country tests, respectively; D, J, and CC: dressage, jumping, and cross-country tests, respectively; 30-D to 90-D: 30–90 min after the dressage test; 30-J to 240-J and 30-CC to 240-CC: 30–240 min after the jumping and cross-country tests, respectively

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  Fig. 3. LF band (A) and HF band (B) in normalised units (n.u.), total power band (C), and LF/HF ratio (D) in response to the three exercise tests and recoveries in the Eventing World Challenge. ⋇ indicates a significant difference from the baseline before the competition (control). λ indicates significant differences between comparison pairs. LF: low-frequency band HF: high-frequency band; W-D, W-J, and W-CC: warm-up before dressage, jumping, and cross-country tests, respectively; D, J, and CC: dressage, jumping, and cross-country tests, respectively; 30-D to 90-D: 30–90 min after the dressage test; 30-J to 240-J and 30-CC to 240-CC: 30–240 min after the jumping and cross-country tests, respectively

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  Fig. 4. SD1 (A), SD2 (B), and SD2/SD1 ratio (C) in response to the three exercise tests and recoveries in the Eventing World Challenge. ⋇ indicates a significant difference from the baseline before the competition (control). # and λ indicate significant differences between comparison pairs. SD1: standard deviation in Poincaré plot perpendicular to the line-of-identity; SD2: standard deviation in Poincaré plot along the line-of-identity; W-D, W-J, and W-CC: warm-up before dressage, jumping, and cross-country tests, respectively; D, J, and CC: dressage, jumping, and cross-country tests, respectively; 30-D to 90-D: 30–90 min after the dressage test; 30-J to 240-J and 30-CC to 240-CC: 30–240 min after the jumping and cross-country tests, respectively

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  Fig. 5. PNS (A) and SNS (B) index responses to the three exercise tests and recoveries in the Eventing World Challenge. ⋇ indicates a significant difference from the baseline before the competition (control). # indicates a significant difference between comparison pairs. PNS: parasympathetic nervous system; SNS: sympathetic nervous system; W-D, W-J, and W-CC: warm-up before dressage, jumping, and cross-country tests, respectively; D, J, and CC: dressage, jumping, and cross-country tests, respectively; 30-D to 90-D: 30–90 min after the dressage test; 30-J to 240-J and 30-CC to 240-CC: 30–240 min after the jumping and cross-country tests, respectively