Lactate and glucose thresholds and heart rate deflection points for Beagles during intense exercise

Abstract

OBJECTIVE To determine whether the lactate threshold of dogs could be determined by a visual method and to assess the extent of agreement and bias among treadmill velocities for the lactate threshold as determined by visual (LTv) and polynomial (LTp) methods, glucose threshold as determined by visual (GTv) and polynomial (GTp) methods, and heart rate deflection point (HRdp) as a method for estimating the aerobic capacity of dogs. ANIMALS 18 healthy adult Beagles. PROCEDURES Each dog underwent a standardized incremental treadmill exercise test once. The test ended when the dog began to show signs of fatigue. Plasma lactate and glucose concentrations and heart rate (HR) were plotted against exercise intensity (treadmill velocity) for the duration of the test, and the LTv, GTv, and HRdp were determined visually. The LTp and GTp were determined by means of a second-order polynomial function. One-way ANOVA, Pearson correlation, Bland-Altman analyses, and ordinary least products regression were used to assess the extent of agreement and bias among the various threshold velocities. RESULTS Mean velocity did not differ significantly among the thresholds evaluated. There was a strong positive correlation between the LTv velocity and the velocity for GTv (r = 0.91), LTp (r = 0.96), GTp (r = 0.94), and HRdp (r = 0.95). CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that LTv could be determined for dogs undergoing intense exercise on a treadmill, and the treadmill velocity corresponding to the LTv was associated with the velocity for the other hallmarks of endurance. Thus, that method may be useful for prescription and evaluation of conditioning programs for dogs.

Benefits of dietary supplements on the physical fitness of German Shepherd dogs during a drug detection training course

“…In our study, median HRdp positioned at the 95% of the peak heart rate and no significant differences were observed between groups. This value was in accordance with that recently found by Restan et al [50] in Beagles. The concordance was not obvious as these authors submitted dogs to a maximal exercise test reaching higher maximum HR (229–291 bpm) and, further, they used visual methods to determine HRdp.…”

“…Submaximal exercise could involve less stress for the animals tested than maximal exercise and, at the same time, induce the increase in blood lactate concentration characteristic of the anaerobic threshold [51]. Indeed, the HR peaks reached by the German Shepherd dogs of the present study (136–193 bpm) were reduced compared to those obtained during maximal exercises [27,50], but similar to those of Beagles subjected to a moderate-intensity exercise (131–209 bpm) [52]. Actually, we cannot confirm the achievement of the lactate threshold in our sample because lactate concentrations during exercise were not determined.…”

“…The HRdp is an inexpensive, non-invasive marker for implementing training programmes and assessing human endurance capacity. Indeed, it is correlated with the anaerobic threshold, the break point between the aerobic and anaerobic metabolism, which is accepted as a measure of an individual’s ability to perform at high intensity for a prolonged period of time [28,29,49,50]. The HRdp appears as a decrease in the HR-work slope during incremental exercise [29,48] and can be determined through visual inspection or mathematical models [27,28,49].…”

“…In the present study, regression techniques were used for HRdp assessment, in order to avoid subjective interpretation [29,45]. Furthermore, unlike previous studies [27,50], we have chosen to undergo animals to a submaximal exercise test. Submaximal exercise could involve less stress for the animals tested than maximal exercise and, at the same time, induce the increase in blood lactate concentration characteristic of the anaerobic threshold [51].…”

Decreased Blood Glucose and Lactate: Is a Useful Indicator of Recovery Ability in Athletes?

“…To measure the exercise capacity, numerous studies have been focused on altered blood glucose concentrations following moderate-to-high-intensity exercise in LT tests. The metabolic changes in blood glucose concentration during low-intensity exercise in LT test are not analyzed [ 2 , 4 , 14 , 15 , 18 , 19 , 20 , 21 , 22 , 23 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ]. Glucose 6-phosphate, supplied through breakdown of muscle glycogen and blood glucose, is metabolized to lactate and re-synthesized to adenosine triphosphate (ATP) by substrate-level phosphorylation reactions [ 34 ].…”