Epsilon Archive for Student Projects

Abstract

Little is known about how the aerobic capacity of endurance horses responds to retraining,
rest, and detraining. In this study, 22 Swedish endurance horses, mainly Arabian horses and
Arabian crosses, were followed for 23 weeks during the off-season in the winter. Data collected
consisted of resting HR, recovery HR, resting respiratory rate, body condition score and HR in
exercise to determine V100 as measurements of aerobic fitness by the means of a standardised
exercise test. Horses were divided to have been resting, trained on lower intensity or trained on
normal intensity in comparison with training efforts during the competition season. Horses were
also divided depending on their prior competition achievements. The aim of the study was to
investigate how different training strategies affect the aerobic fitness of endurance horses, in
order to get a better understanding how to train and manage the endurance horse for optimal
performance. Four horses went through a resting period of 7-14 weeks. After 7 weeks of rest, no
changes in aerobic fitness was measured, whereas after a 10-week rest, horses showed a minor
decrease in V100. After 14 weeks of rest, one horse showed a 17% decrease in V100 and an
increased resting and recovery HR. The horses resting for 7-10 weeks increased in V100 after
their resting period and improved with up to 24% from the initial pre-resting measurements.
Horses trained at normal intensity showed higher recovery HR at the later stage in the collection
period - suggesting potential lowered aerobic capacity after long-term training -, but otherwise
horses trained at lower or normal intensity showed no changes in aerobic fitness throughout the
project. Horses at higher competition levels had a tendency for lower rest HR, quicker recovery
HR and a higher V100. Horses with a body condition score under 4 out of 9 were more prone to a
decrease of aerobic fitness. Respiratory values did not change whatsoever during the collection
period in any of the horses. Combining previous literature and the findings from this study, it can
be concluded that endurance horses can be rested for 6 weeks without losing aerobic fitness,
however more research is necessary to draw stronger conclusions on this topic.