SC IENCE OF
MAN V HORSE
AN ANALYSIS OF HOW A HUMAN MAY BE A BLE TO RUN
FASTER THAN HORSES IN A LON G ENDURANCE EVENT.
INTRODUCTION
The annual Man vs Horse Marathon (MVH) takes place
across the demanding terrain of Llanwrtyd Wells, Wales.
The typically 22 mile (35 km) race has produced just two
Homo sapien winners in its 35 year history. This article aims
to explore the contributing factors that may allow man to
triumph. Firstly, the results history of the race will be analysed
to identify the required endurance capacity of any potential
human victor. Secondly, a physiological and biomechanical
comparison between the two species will be made to identify
strengths and weaknesses of each. Thirdly, the environmental
conditions of the race itself will be considered including an
analysis of the course route and potential weather conditions
that may increase the probability of a human athlete
succeeding. Finally, this article will aim to identify possible
performance enhancing strategies for athletes to use in
their training to enhance their physiological responses.
DISCUSSION
The first athlete to win this famous race since its creation
in 1980, was Huw Lobb in 2004, with a time of 2:05:19.
Florian Holzinger repeated the feat in 2007 with a time of
2:20:30. However from 2008 to 2013 the time difference
between athlete and horse increased each year and is
currently at 19 minutes and 56 seconds in favour of the
horse. Since the course alteration in 1982, the mean
winning equine time is 116.9 (± 17.4) minutes whilst the
mean winning individual running time is 134.5 (± 11.0)
minutes. Winning times vary considerably depending on the
course route and weather conditions on race day. However,
through using the mean winning individual running times
over the past 33 years, we would suggest that runners
would need a marathon time of less than 2:40:00 (this
equates to a 3:48 min/km or 6.07 min/mile pace) to have
a good chance of being the fastest athlete. To have a good
chance of beating the fastest horse, the fastest athlete
would need a marathon time of less than 2:20:00 (this
equates to a 3:20 min/km or 5:21 min/mile pace).
Fi gure 1. Fastest wi nni ng times (mi nutes) by horse (b lue) and athlete (red) si nce 1982.
Before discussing potential methods an athlete may be able to use to enhance their chances
of beating the horse, it is important to first understand the physiological strengths of horses
in comparison to humans. Table 1 shows a comparison of key race statistics.
Tab le 1. Comparison o f key physio logica l performance parameters
between e lite endurance runners and e lite endurance horses.
Parameter
Max HR (bpm)
Stroke Volume (l)
Maximum Cardiac Output (l/min)
Total Lung Volume (L)
VO2 max (ml/min/kg)
Lactate Tolerance (mmol/L)
Maximal Haematocrit (%)
Horse
240-250
0.8-1.2
300
55
160-170
30
65
Human
220-Age
0.2
35
6
80
4
45
As Table 1 shows, horses have a huge advantage over humans in terms as their physiological
characteristics, allowing them to deliver and utilize oxygen to the working muscles very
efficiently in comparison to humans. Elite horses are able to reach maximum running velocities
of 80 km/h in comparison to a mere 44 km/h for Usain Bolt. There is large difference at
first glance at the physiological capabilities between humans and horses. However it is
possible for a human to beat the horse, as both Huw Lobb and Florian Holzinger proved.
Despite the physiological advantages horses possess
over humans, humans do possess a biomechanical
advantage over horses. Both humans and horses exploit
the mass-spring mechanism when moving. Collagenrich tendons and ligaments in the leg store elastic strain
energy during the initial support phase of a gait and then
release this energy in the propulsive phase of the stride
through recoil. This helps reduce the metabolic cost
of transport in both species. Horses have a U-shaped
metabolic cost of transport curve when galloping, which
means that they have a narrow range of preferred speeds
to minimize metabolic cost. In comparison, humans have
a relatively flat shaped curve, allowing them to continually
adjust running speed without a change of gait or a
metabolic cost over a large range of speeds (Figure 2).
Fi gure 2. Comparison o f the metabo lic cost
o f transport (COT) i n humans and horses.
Dotted rectangles represent the mostenergy efficient speeds. Source: Bramb le. D.,
& Lieberman. D. (2004).
Humans also increase their running speed through
increasing their stride length rather than their stride rate
(speed = stride length x stride rate). As a result of this,
humans keep relatively long ground contact times which
helps reduce the metabolic cost of transport. In contrast,
horses tend to increase their stride rate greater than
humans, which requires a greater metabolic cost to oscillate
their long legs. It is believed that humans’ biomechanical
running style has evolved to be ideally suited for long
distance running due to the hunter-gatherer origins of
Homo sapiens, allowing them to run many mammals to
exhaustion before capturing them. This biomechanical
advantage over long distances is also aided by a high
percentage of slow twitch muscle fibres. Elite marathon
runners have been shown to have more than 80% of slow
twitch muscle fibres. These contract more slowly than
fast-twitch muscle fibres, are more efficient in utilizing
oxygen and have a greater resistance to fatigue, making
them ideal for long distance running. In comparison,
horses tend to be more predominant in fast twitch muscle
fibres which fatigue faster, are less efficient at utilizing
oxygen and therefore are less suited to endurance riding.
A potentially significant biomechanical difference between
horses and humans when running or galloping is that humans
are able to run at a higher percentage of their maximum
running velocity at the same gradient decline compared to
horses. Whilst horses reach their maximum running velocity at
0% gradient, humans actually run fastest on a decline of around
0.1-0.2% (Self et al., 2012). This is due to potential energy
from a decrease in height from centre of mass being absorbed
by the muscoskeletal system. In comparison, it is thought that
horses run slower at a decline due to the anatomical nature
of their front legs which limits weight support and stability. In
contrast, both humans and horses move slower when running
on an incline due to having to perform mechanical work to raise
their centre of mass against the effects of gravity. Evidence
comparing the percentage decrease in speed as incline
increase between the two species suggests that horses may
actually slow down marginally less quickly when running up the
same gradient incline compared to humans. It is therefore vital
that runners in MVH ensure that they take advantage of the long
and steep descents in the race to regain time lost over the flat.
The 2015 MVH route is summarised in Table 2 and Figure 3.
Horses
Athletes
Total distance (km)
38.5
33.7
Total Ascent (m)
1584
1393
Total Descent (m)
1553
1362
Climb 1
Distance of climb (km)
6.9
7.5
Climb 1
Average gradient (%)
3.2
3.0
Climb 2
Distance of climb (km)
2.8
3.0
Climb 2
Average gradient (%)
5.9
5.6
Climb 2
Distance of climb (km)
5.7
5.7
Climb 2
Average gradient (%)
4.1
4.1
Tab le 2.
Course breakdown for horses and athletes.
Fi gure 3. Route pro fi les for horse rider and runners.
One factor that may play a significant role in allowing an
athlete to beat the horse is the effect of the race-day weather
conditions. Chemical energy in the form of ATP is transformed
into mechanical energy in the form of locomotion with energy
lost from this system in the form of heat energy. To dissipate
this heat from the body, in both humans and horses, the
hypothalamus in the brain stimulates blood vessels near the
skin to dilate to allow heat to leave the body through sweat
and convection. Around 20% of chemical energy in a both
species is converted to mechanical energy, with the majority of
the remainder transformed into heat energy. However, horses
are less efficient at maintaining their core body temperature
compared to humans as their surface area to body mass ratio
is 40% lower, lowering their ability to dissipate heat as quickly.
Dehydration of around 2-4% of body weight during endurance
exercise has shown to significantly impair performance
in humans. In comparison, a study amongst six horses
completing prolonged endurance exercise, showed an average
weight loss of 6% at a 21°C despite regular access to water.
Horses struggle to maintain their core body temperature
during prolonged endurance exercise and with sweat rates
approaching 10-12 litres per hour means they often suffer from
heat stress which negatively influences their performance. In
both 2004 and 2007 (the only 2 human triumphs) the weather
conditions were said to be ‘hot’ suggesting that weather
conditions may be a key determining factor in performance of
the horse. Whilst horses may struggle to prevent dehydration,
athletes are able to prevent dehydration limiting their
performance on race-day. The best method to determine an
athlete’s sweat rate during long endurance exercise is:
1.Weigh athlete before a long run with
minimal clothing (Pre) (kg)
2. Weigh fluids consumed during exercise prior (Fluids) (kg)
3.Weigh athlete immediately post-exercise with exactly
the same clothing as pre-exercise (Post) (kg)
4. To calculate athletes’ sweat loss: (Pre – Post) + (Fluids)
By using the above method, runners in MVH can ensure that
they consume the correct amount of fluid during the race
to prevent dehydration occurring and thereby gaining an
advantage over the horse. Long endurance events in a hot
environment will not only result in a high volume of sweat
but will also result in the loss of important electrolytes. Of
particular importance is the loss of sodium. Carrying out
vigorous exercise in a hot environment, an athlete may lose
more than 1000 mg of sodium per day through perspiration.
Sodium is necessary to maintain homeostasis and is vital in
the repolarisation-depolarisation of muscular contractions,
therefore a combined loss in sweat loss and a loss in sodium
from the blood stream will result in a reduced blood volume
and therefore a lower blood pressure, reducing the ability of
the cardiovascular system and impairing performance. It is
therefore advisable that athletes taking part in MVH ensure
they preload on sodium (Coles & Luetkemeier., 2005) before
the race to ensure a sufficient electrolyte balance throughout
the race. A good guideline to follow would be to consume
1500 mg of sodium per litre of water around 2 hours before
the race. Although riders are likely to supplement their
horses before and during the race, their sodium losses are
significantly higher than humans and therefore it is difficult
to maintain their electrolyte balance. Horses trotting for 45
km in ambient conditions have been shown to lose more
than 80 g of sodium (Kingston et al., 1999). Through using
these methods, athletes can ensure that their performance
is not inhibited by high temperature and high humidity on
race-day, giving them a significant advantage over horses.
An effective training programme should also include a
balanced diet and appropriate meals pre and post training.
Recovery nutrition has the aims of replenishing muscle
and liver glycogen stores, replacing fluid and electrolytes
lost in sweat, synthesising new muscle protein, stimulate
haematopoiesis, and allowing the immune system to cope
with the damage caused by exercise. Eating appropriately
post exercise will help to reduce recovery time, maximise
muscle repair and replace energy stores lost during prolonged
exercise. Peanut butter is an ideal post-exercise food source
following long endurance training. Whole Earth Original Peanut
Butter contains 26.3 g of protein per 100 g. Long endurance
exercise causes an increase in catabolic processes within
the muscle but recovery results in an increase in anabolic
processes. Consuming protein post-exercise (around 15-25
g within the first hour) is thereby crucial to help maximise
protein synthesis in the muscle fibres to reduce recovery
time. Peanut butter is an excellent source of protein for this
purpose. Research (Ivy et al., 2008) suggests that consuming
protein with carbohydrates following endurance exercise,
enhances the rate of glycogen (energy source) replenishment.
By combining the two energy sources, blood glucose levels
rise less rapidly, promoting the liver to convert glucose to
glycogen instead of fat. This is important to ensure energy
stores are maximised as quickly as possible and to allow
the body to recover appropriately before training again.
There are several supplementation methods that runners
competing in MVH can use either in training or on race-day
to enhance their performance and reduce their race time.
One of these is carbohydrate loading. This is a strategy
involving manipulation of training and nutrition in the week
prior to the MVH to maximise muscle glycogen stores. It is
recommended that athletes consume a high carbohydrate
diet (7-12 g per kg of body weight) within 4 days of the race
whilst tapering their training regime. This method has been
shown to increase muscle glycogen stores by up to 50% and
will allow runners to maintain their optimal race pace for
a longer period time by delaying the body’s need to utilize
fat stores which are less oxygen efficient and are slower to
break down. It is advisable that athletes using this method
should trial it during training at least 3 times before raceday to make you they are comfortable with the process.
Nitrate supplementation in the form of beetroot juice
has been shown to significantly improve running
performance. Nitrate reduces the oxygen cost of
submaximal exercise by reducing the ATP cost of muscle
contraction. Therefore the fuel efficiency of muscles
is increased, allowing athletes to spare fuel stores for
later in the race. It is recommended that runners should
consume a 0.5 litres of beetroot juice 2.5 hours before
a race to see optimal benefits (Lansley et al., 2011).
CONCLUSION
REFERENCES
Despite horses possessing a substantially greater
physiological capacity over humans; there are areas in
which athletes competing in MVH can exploit weaknesses
of the horse. Humans have a biomechanical advantage over
horses when running downhill and have been evolutionarily
geared towards endurance running. By following the correct
hydration and sweat replacement strategies, humans
can also ensure they are not limited by the environmental
conditions as horses are likely to be. There are also potential
nutritional strategies that a human can utilize in training and
on race day to maximise their running capacity, including
consuming sufficient protein and carbohydrate post training,
carbohydrate loading and nitrate supplementation.
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Ivy, J. L., Ding, Z., Hwang, H.,
Cialdella-Kam, L, C. & Morrison, P.J. (2008)
Post exercise carbohydrate-protein supplementation:
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Kingston, J.K., McCutcheon, L.J., & Geor, R.J. (1999).
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sweat of horses. American Journal of Veterinary Research, 60, 1248-1254.
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