Racing speeds of Quarter Horses, Thoroughbreds and Arabians

Abstract

While Quarter Horses are recognised as the fastest breed of horse, direct comparisons to race times with other breeds can be misleading. Quarter Horse races begin when the starting gates open. Thoroughbred and Arabian races begin a short distance from the gates after horses have started running. This study compared speeds of these breeds as they accelerate from the starting gates and during the middle and end of races.
To compare racing speeds of the 3 breeds, and to compare speeds during various segments of the races.
Video tapes of races were obtained from a local track. The various race segments were viewed and the winning horse timed by 5 individuals. Fastest and slowest times were removed and the 3 remaining times averaged.
Quarter Horses averaged faster speeds than Thoroughbreds even when Thoroughbreds were raced at a distance (402 m) similar to Quarter Horse races. Both breeds were substantially faster than Arabians. Quarter Horses racing 336 m or less gained speed in each segment of the race while Arabians and Thoroughbreds racing 1006 m ran fastest during the middle of the race and had decreased their speed in the final segment of the race.
Despite similar race times reported for 402 m, Quarter Horses averaged faster speeds than Thoroughbreds when timed from a standing start. In short races, both breeds accelerate throughout the race. Arabians, despite being known for endurance, had slowed by the end of the race.
This study demonstrates that Quarter Horses achieve faster racing speeds than do other breeds. It also reveals a potential flaw in race-riding strategy as a more consistent pace throughout the Arabian and longer Thoroughbred races may be more efficient and result in a faster overall race time.

Full text

128
EQUINE EXERCISE
PHYSIOLOGY
7
Equine
r~.
J.,
Suppl.
36
(2006)
128-132
Racing speeds
of
Quarter Horses, Thoroughbreds and
Arabians
B.
D. NIELSEN’,
K.
K.
TURNER,
B.
A.
VENTURA,
A.
D. WOODWARD
and
C.
1.
O’CONNOR
Michigan State University, 1287 Anthony Hall, East Lansing, Michigan 48824,
USA.
Keywords:
horse; Quarter Horse; Thoroughbred; Arabian;
race;
speed
S
u m m a
r
y
Reasons
for
performing
study:
While Quarter Horses are
recognised as the fastest breed of horse, direct comparisons
to race times with other breeds can be misleading. Quarter
Horse races begin when the starting gates open.
Thoroughbred and Arabian races begin a short distance
from the gates after horses have started running. This study
compared speeds of these breeds as they accelerate from the
starting gates and during the middle and end of races.
Objectives:
To compare racing speeds of the
3
breeds, and to
compare speeds during various segments of the races.
Methods:
Video tapes of races were obtained from a local
track. The various race segments were viewed and the
winning horse timed by
5
individuals. Fastest and slowest
times were removed and the
3
remaining times averaged.
Results:
Quarter Horses averaged faster speeds than
Thoroughbreds even when Thoroughbreds were raced at a
distance
(402
m) similar to Quarter Horse races. Both breeds
were substantially faster than Arabians. Quarter Horses
racing
336
m or less gained speed in each segment
of
the race
while Arabians and Thoroughbreds racing
1006
m ran
fastest during the middle of the race and had decreased their
speed in the final segment of the race.
Conclusions:
Despite similar race times reported for
402
m,
Quarter Horses averaged faster speeds than Thoroughbreds
when timed from a standing start. In short races, both breeds
accelerate throughout the race. Arabians, despite being
known for endurance, had slowed by the end of the race.
Potential relevance:
This study demonstrates that Quarter
Horses achieve faster racing speeds than do other breeds. It
also reveals a potential flaw in race-riding strategy as a more
consistent pace throughout the Arabian and longer
Thoroughbred races may be more efficient and result in a
faster overall race time.
Introduction
The general public tends to view Thoroughbreds as the fastest
racehorse,
a
view reinforced by the disproportionate amount
of
televised Thoroughbred racing
as
compared to other breeds.
However, the American Quarter Horse is generally recognised by
horsemen as the fastest breed. The name of this breed reflects its
reputation as the fastest horse at a quarter
of
a mile (402 m). The
speed and acceleration of
a
Quarter Horse is fast enough that
jockeys who have only ridden Thoroughbreds have been left in the
starting gates as their Quarter Horse mounts rapidly accelerate
when the races start, therefore providing evidence of the Quarter
Horse’s quickness. In contrast, the Arabian’s prowess
is
as an
endurance athlete (Hoffman
et
ul.
2002)
and is better suited for
racing longer distances. Due to time constraints at horse racing
tracks and interests
of
the betting public, parimutuel Arabian races
are usually contested at similar distances to Thoroughbreds,
despite being substantially slower.
Even though many horsemen recognise the differences in
speed between these various breeds, confusion occurs when
racing times are compared. The current world record for 402 m
by a Quarter Horse is 20.686 sec (Anon 2005a). By contrast, the
world record for Thoroughbreds racing
402
m
is
20.8 sec (Anon
2005b). This relative lack of difference appears to be in
disagreement with the belief that the Quarter Horse
is
the fastest
breed of horse at that distance. However, a major difference in the
method used to time Quarter Horse races as compared to
Thoroughbred and Arabian races renders the comparison faulty.
While Quarter Horse races are timed from the moment the
starting gates open, time in Thoroughbred and Arabian races
begins when the horses cross in front of a flagman stationed a
short distance in front of the gates. When the flagman drops the
flag, the race begins (Ainslie 1986).
As
a
result, Quarter Horse
races begin from a standing start while Thoroughbred and
Arabian races begin when horses are already running. Using
a
high-speed camera, Pratt
(199
1)
determined that the interval from
when the starting gates began to open until they were fully open
was 0.35 sec. After the gate was wide open, it took another 0.23
sec for the first foreleg to come down in the first jump out of the
starting gates. Therefore, nearly
0.6
sec elapse from the time the
race begins until a Quarter Horse has taken a step away from the
gates. This difference in timing techniques explains why racing
Quarter Horses are deemed faster by those that ride them but are
not substantially faster according to record times.
While recorded times for Arabians are slower than
Thoroughbreds, the opportunity to compare this breed to the
2 faster breeds may show differences in racing patterns. In work
conducted by Pratt
(1991),
the fastest speed reached by a Quarter
Horse during a 402 m race occurs when the horses have raced
about 230 m
-
after that, speed declines. Rarely in Thoroughbred
races are speeds at the end of
a
race greater than during the
beginning or middle (Ainslie 1986). Considering the Arabian
breed’s reputation for endurance, one might expect this breed to be
better able to sustain its speed throughout a race.
The first hypothesis of this study is that Quarter Horses
achieve faster speeds than do Thoroughbreds and that Arabians
‘Author
to
whom correspondence should be addressed.

B.
D.
Nielsen
et
al.
129
have the slowest maximal speed of all the 3 breeds. A second
hypothesis is that Arabians are better able to sustain their maximal
speed than are Quarter Horses and Thoroughbreds.
Materials and methods
Selection
of
races
Results from all races conducted during the 2005 race meet at
Mount Pleasant Meadows (Mount Pleasant, Michigan, USA) were
obtained weekly from Equibase
(http://www.equibase.com).
This
represented 36 days of racing and provided the unique opportunity
to compare racing times of Quarter Horses, Thoroughbreds and
Arabians
-
all racing on the same track on the same days. Races at
the distances of 302, 366 and 402
m
were chosen for further
review for Quarter Horses, 402 and 1006 m for Thoroughbreds,
and 1006 and 1207 m for Arabians. The five fastest races at each
of these distances within a breed (except for 402 m for Quarter
Horses) were determined and video-tapes of those races obtained
from Mount Pleasant Meadows. These distances were selected in
an attempt to compare speeds between breeds when raced at
similar distances. In addition, more than one distance for each
breed was chosen to allow for comparisons of speeds at various
distances within a breed. The minimum distance of 302 m was
chosen for Quarter Horses
so
that segments of the races to be timed
would not overlap while still allowing race segments to be roughly
100 m. It was felt segments shorter than that would amplify the
error associated with inaccuracies in timing. Only
2
Quarter Horse
races were run at 402
m,
therefore necessitating the inclusion of
the distance of 366 m to allow sufficient numbers
of
a similar
distance for adequate statistical analyses. Preferably, a distance
longer than 1207 m would have been available for Arabians.
However, only one longer race
(1980
m) was run during the meet.
Race track
dimensions
Mount Pleasant Meadows track design consists of an
805
m oval
with a chute on the grandstand side stretching for 402 m to the
finish line (Fig 1). For Quarter Horse and Thoroughbred races of
402 m, the entire race was conducted in a straight line starting in
the chute and finishing in front
of
the grandstand. For the 1006 m
Thoroughbred races and for all of the Arabian races, the races
started in the chute, continued around the oval and finished in
front of the grandstand.
Timing
All of the selected races were watched and timed by the same
5
individuals. Each individual used a stopwatch capable of
measuring to one-hundredth of a second. To obtain an estimate of
the accuracy of timing, each race was hand-timed by stopwatch to
be compared to the official time of the race as reported by
Equibase. After the entire race was timed, individual segments
from the beginning, middle and end of each race were timed.
Timing of the beginning segments began when the horses left the
starting gates and ended when horses passed by the pole
representing a distance closest to 100 m from the start of the race.
Due to flagging of the start in some Thoroughbred and Arabian
races, the actual distance of the initial segment varied and was
taken into account when calculating average speed of the initial
race segment. For the ,302 m Quarter Horse race, the middle
segment was timed between the poles at the
201
and 101 m. For
the Quarter Horse races at 366 m, and the Quarter Horse and
Thoroughbred races of 402 m, the middle segment was timed
between the poles set 274 and
201
m from the finish line. For the
Fig
1:
Overhead view
of
Mount Pleasant Meadows with starting points
of
various race distances
(-),
the finish line
(0)
and placement
of
cameras
used
to
film the races
(0).
Thoroughbred races at
1006
m and for all of the Arabian races, the
middle segment was timed between poles set at SO3 and 402 m
from the finish line on the backside of the oval. For all races, the
end segment was timed from the pole set at the 101 m mark to the
finish line.
From the
5
times for the entire race and for each of the race
segments, the slowest and fastest times were thrown out and the
3 remaining times averaged. The average time for each race
segment was divided by the distance of each segment to determine
the average speed during that segment of the race.
Statistical analyses
Linear regression was applied to the average hand-times of the
entire races compared to the official race times as obtained from
Equibase and the correlation between the two was determined.
Analysis of variance was performed using SuperANOVA' to
determine differences in overall speed between breeds, at each
segment between breeds, within a breed at each distance, and
within a breed at each segment.
Post hoc
analysis using Fisher's
Protected LSD was used for mean separation. Differences were
considered significant at P<O.OS.

I30
Racing
speed\
of
Quarter
Horses,
Thoroughbreds
and Arabians
TABLE
1:
Mean speeds
*
s.e. (kmlh) of the beginning, middle and final
segments of Quarter Horse
(QH),
Thoroughbred (TB) and Arabian (AR)
races
Breed Overall Race segment
BeginningA MiddleB FinalB
QH
70.7f4.0a 39.1 *1.4x 81.5+2Say 91.5+1.8aZ
TB
58.0f3.5b 36.8i0.8' 68.0i3.5by 69.1 f5.3by
AR
44.7
f
1.5c 34.9
f
1.2' 52.4
*
O.gCy 46.8
f
0.8cY
abc
Means within a column not sharing a similar superscript differ
(Ps0.05).
xYz
Means within a row of race segment not sharing a similar superscript differ
(P50.05).
AB Overall race segments not sharing the same superscript differ
(P<0.05).
TABLE
2:
Mean speeds
*
s.e. (kdh) of the beginning, middle and final
segments
of
Quarter Horse
(QH),
Thoroughbred (TB) and Arabian (AR)
races at various distances
Breed Distance (m) Race segment
BeginningA MiddleB FinalC
QH
302 42.8
i
2.ZX
77.5
f
3.gby 92.6
f
3.5*
QH
366 36.7
f
0.gx 81.2
i
2.4by 91.3
f
2.62
QH
402 35.9
f
4.P 92.4
i
7.Zay 89.3
f
0.3y
BeginningA MiddleB FinalB
TB"
402 36.1
f
1
.LTX
76.4
f
4.6ay 83.9
f
4.1ay
TB
1006 37.5
+
0.5' 59.6
f
OBbZ
54.2
f
0.7by
BeginningA MiddleC FinalB
AR"
1006 37.3
f
1
.Oax
54.6
f
0.7az 46.1
i
0.W
AR
1207 32.6
f
1 .7bx 50.3
f
0Bby
47.5
i
1.4Y
abc Means within a column
not
sharing a similar superscript differ
(PS0.05).
xYz
Means within a row
of
race segment not sharing a similar superscript differ
(PS0.05). Overall race segments not sharing the same superscript differ
(P<0.05).
**
Shorter distance within a breed is significantly faster than the
longer distance
(P<O.OOI).
Results
There was strong correlation between official race times and race
times clocked via a stopwatch (r2
=
0.999). When all distances and
segments of races were combined, Quarter Horses were faster than
Thoroughbreds, and Thoroughbreds were faster than Arabians
(Table
I;
P<O.OOOl).
No
difference in speed during the beginning
segment of the races was seen between breeds, but Quarter Horses
were faster than Thoroughbreds
(P50.0002)
and Thoroughbreds
were faster than Arabians
(P<O.OOOI)
during the middle and final
segments of the races. The average speed of the beginning
segment for
all
breeds over all distances was slower than the speed
during the middle and final segments. Only with Quarter Horses
was speed increased in the final segment as compared to the
middle segment
(P<O.OOOI).
No
differences were seen in the overall average speed of
all
segments for the
3
Quarter Horse race distances (Table
2)
though
the speed in the middle segment was faster at 402 m when
compared to the other
2
distances. The speed of the final segment
had increased over the middle segment for the
2
shorter distances
but was unchanged at 402 m. Average speeds in 402 m
Thoroughbred races were faster than in
1006
m Thoroughbred races
(P<O.OOOl),
with the beginning segment slower than middle and
final segments
(P<O.OOOI).
At
1006
m, the middle segment was the
fastest
(P<O.OOOl).
Arabian races at
1006
m were faster than
Arabian races at 1207 m
(P
=
0.01).
As with the other breeds, the
TABLE
3:
Comparisons between breeds of mean speeds
f
s.e.
(km/h) at
similar distances in the beginning, middle and final segments of races
Breed Distance
(m)
Race segment
~
BeginningA MiddleB FinalC
OH'
3661402 36.4
f
1.1 84.4
f
2.4Y 90.7
f
1.9Y
TB
402 36.1
f
1.5~ 76.4
f
4.6Y 83.9
f
4.1y
BeginningA MiddleC FinalB
TB*'
1,006 37.5
f
0.5x 59.6
f
0.8az
54.2
f
0.7ay
AR
1,006 37.3
f
1
.Ox
54.6
i
0.7bZ 46.1
i
0Bby
abc Means within a column not sharing a similar superscript differ
(P<0.05).
'YZ
Means within a row
of
race segment not sharing a similar superscript
differ
(P<0.05).
Overall race segments not sharing the same superscript
differ
(P<0.05).
*
Quarter Horse faster than Thoroughbred
(P<0.05).
**
Thoroughbred faster than Arabian
(P<O.OOl).
beginning segment of the Arabian races was the slowest
(P<O.OOOl).
With the race distances combined, the middle segment
was the fastest with the speed decreasing
(P<O.OOOl)
by the end of
the races. Individually, this decrease was only significant at 1006 m
(P<0.0001)
though there was
a
trend for a decrease in speed from
the middle to final segments at 1207 m
(P<O.
1).
As
there were no differences in speeds of Quarter Horses in
races of 366 and 402 m, the data was pooled for comparison to
Thoroughbred speeds at 402 m (Table 3). The overall average
speed of segments from Quarter Horse races was faster than the
Thoroughbred races
(P
=
0.037) with the overall average speed for
all horses racing this distance increasing during each segment.
Individually, there was only
a
trend
(P<O.l)
for both breeds to
increase speed from the middle
to
the final segment. At 1006 m,
the overall average speed
of
segments from Thoroughbred races
was faster than that of Arabian races
(P<O.OOOl).
In contrast to
shorter races, the middle segment at for
all
horses racing 1006 m
was the fastest
(P<O.OOO
1
),
while the beginning segment remained
the slowest
(P<0.0001).
Discussion
The strong correlation between official race times and times
determined via stop-watch is expected. At the shortest distances
clocked (302 m), the fastest official time was 16.900 sec.
A
95%
accuracy in timing would allow the hand-time to be off by as
much
as
0.845 sec. Being that inaccurate is unlikely given that
5
individuals performed the timing and the highest and lowest
values were excluded. At the far extreme is the longest race timed
-
a 1207 m Arabian race that took 87.0 sec.
A
5%
error would be
4.35 sec, which is extremely unlikely. This strong correlation also
provides some support that this method of determining racing
speeds has some validity.
Some limitations do exist with this method. To begin with, the
segments being clocked are much shorter than the entire races. For
the shortest Quarter Horse races, each segment would consist of
roughly one third
of
the time (different speeds during each segment
accounting for the differences). Thus, the degree to which
inaccuracies in timing alter the calculated speed is amplified.
Additionally, while it is easy to see when the starting gates open, a
flag is dropped, or when a horse crosses the finish line (all
necessary in determining the time of
a
race), determining when a
horse passes a pole to start or end a race segment is much more
difficult, especially when the cameras used to film the races
are
at
an angle or head-on. The greatest discrepancy between the actual
time to cover a segment of the race and the times established
through hand-timing should occur in the beginning segment of the

B.
D.
Nielsen
et
al.
131
366,402 and 1207 m races. Those races are started furthest from
the cameras which results in the greatest angle of vision when
horses finish that segment. The average variation amongst all five
times for the beginning segments of all races at those distances was
12.7%, which, while not great, reflects some inaccuracy in the
methodology. As a result, though these values are useful in
comparing various breeds and also various segments of races, they
are somewhat limited in their ability to accurately determine
speeds. Therefore, the speeds calculated should be viewed in
relative terms to each other and not as absolutes. A more accurate
way to determine speeds would be to be present on race days and
have individuals posted at the various segments around the track.
This would require being available on every race day, extensive
man-power and a need to have a complete set of timers for every
horse in a race. Furthermore, the racing stewards had concerns that
having individuals stationed around the track might distract horses
and interfere with race results. For these reasons, the procedures
used in this study were implemented despite known limitations.
That being said, this study supported the hypothesis that
Quarter Horses are faster than Thoroughbreds and that
Thoroughbreds are faster than Arabians at typical racing distances
at the track studied. When comparing submaximal effort,
Cikrytova
et
al.
(1991) reported velocity at a heartrate of
170 beats/min to be 10.35 dsec in Thoroughbreds while only
8.15 dsec in Arabians. The difference in speed is supported by
research that reported Arabian horses have a higher proportion of
types
I
and
IZa
muscle fibres as compared to Thoroughbreds that
have a greater proportion type
IIx
(Lopez-River0 and Letelier
2000). While environmental factors such as training likely have
some influence
on
these differences, genetic differences between
breeds play an important role. Cunningham (1991) concluded that
35% of variability in athletic performance in Thoroughbreds is
due to hereditary factors. Likewise, the heritability of speed in
Quarter Horses has been estimated to be 24% (Willham and
Wilson 1991) and the heritability of racing times for Arabians
racing 1200 m has been estimated to be 27.8%
(Ekiz
et
al.
2005).
Not surprisingly, this study also showed that the initial race
segment was the slowest. However, the failure to detect
differences in speeds during the initial segments is surprising.
Race riders of the 3 breeds attest to differences in acceleration
away from the starting gates. Possible reasons for this failure
to
detect breed differences include the exact end of the beginning
segment being difficult
to
detect. The segment occurs in the chute
and the camera is at a greater angle to the end of that segment than
any other
-
adding a greater degree of uncertainty as to when to
stop timing the beginning segment. Additionally, Quarter Horse
races begin when the starting gates open while Thoroughbred and
Arabian races typically include an additional distance to run after
leaving the starting gates before the race officially begins. This
additional distance was factored into the measurements and
timing. While it was taken into consideration, it did afford roughly
an additional 10 m to be included into the beginning segment of
those races to determine the average speed. As a result, Quarter
Horses typically had a
100
m section from which to determine the
average speed, whereas roughly a
110
m section was used in races
where a flagman signaled the race start. Therefore, a longer period
for acceleration was allowed, thereby increasing the average speed
of that section. This was a recognised limitation in calculating
speed during the beginning segments of the races. However, given
that the poles
on
the racetrack were the markers available for
timing, it could not be reasonably altered.
The dramatic increase in speed during the middle segment of
the 302 m Quarter Horse races, and also in the 366 m races,
suggest that the horses had not reached their peak speeds during
those segments. Pratt
(1991)
calculated that peak speeds in horses
racing 402 m occurred at about 230 m and that the horses had
slowed by the end of the race. All, or most, of the middle segment
in the 302 and 366 m races had been completed before the horses
would have reached peak speeds. While Pratt (1991) only
evaluated 2 animals, our work supports similar conclusions that
Quarter Horses
are
still accelerating during the middle part of
races of 366 m or less.
While Thoroughbreds racing 402 m showed a trend for
increased speed from the middle
to
final segments (P
=
0.055),
Thoroughbreds racing 1006 m had decreased speed between those
2 segments. As would be expected, Thoroughbreds racing a
shorter distance had faster average speeds than those racing the
longer distance. The same was true with Arabians having faster
speeds when racing 1006 m as compared to 1207 m. Similar to
Thoroughbreds, the Arabians had slowed down from the middle to
the final segments at 1006 m and had a trend for slowing down
between these segments at 1207 m (P<O.l). This failure to
maintain a constant speed during the duration of the race refuted
the hypothesis that Arabians in this project would be able to
maintain their speed. While known for their endurance, these
Arabians raced at distances that arguably
are
sprints and
are
not
capitalizing on the Arabian breed’s natural endurance. This failure
to maintain speed also suggests that the races were not being
ridden in a manner to ensure maximum performance. Most human
distance world records set in the last decade have been set in
‘almost metronome-like pacing’ (Cooper 2005). Assuming the
same principle applies to horse racing, a more consistent pace
likely would allow for a faster finishing time. Interestingly, it was
noted that frequently the horses that won these longer races often
lead the race from start to finish. This does not negate that
changing racing techniques allowing slower fractions during the
middle of the race should allow faster fractions at the end of the
race and potentially a better overall performance. However, riders
are hesitant to get too far behind in a Thoroughbred
or
Arabian
race even though
it
might improve their horses’ performance.
While there were differences in speed with Quarter Horses
being the fastest and Arabians being the slowest, these results
were expected. Shorter races involve maximum acceleration
without concern for pace. In longer races, pacing the horse to
allow sustained speed is advisable. A fairer assessment of speed is
to compare breeds at a similar distance. While it would have been
ideal to have sufficient numbers of Quarter Horse races at 402 m
to adequately compare to Thoroughbreds at the same distance,
since only 2 Quarter Horse races were run at this distance, it was
deemed necessary to also time races at 366 m which represented
the distance closest to 402 m that is run in Quarter Horse meets.
Since the overall speeds of those 2 distances did not differ, it
seemed reasonable to pool the data. Upon doing
so,
the
comparison demonstrates that Quarter Horses were faster than
Thoroughbreds when raced at similar distances. Similar
comparisons between Thoroughbreds and Arabians also
confirmed that Thoroughbreds are faster than Arabians when
raced at a distance of 1006 m. While comparisons of speeds
between Thoroughbreds and Arabians have been made previously
with Thoroughbreds being faster when running at
V02max
(Prince
et
al.
2002), to the authors’ knowledge, no comparison of speeds
between Quarter Horses and Thoroughbreds competing at a
similar racing distance has been made.
Acknowledgements
Special thanks go to Bob Evans, Racing Secretary at Mount
Pleasant Meadows, for his assistance with this project.
Additionally, we wish to thank the track starter, Bob Williams, for
his guidance in conducting this work.

132
Racing
\peed5
of
Quarter
Horse,.
Thoroughbred5 and Arabian,
Manufacturer's address
'SuperANOVA
vI
.I
1.
Abacus Concept\.
Inc
,
Berkeley. California. USA.
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lY86J
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World
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