The document provides an overview of common medical issues that can occur at marathons like the 2014 Cork City Marathon. It discusses conditions such as hyperthermia, hyponatremia, hypothermia, and exercise-associated collapse that are often seen in runners. It also outlines case studies of runners experiencing various medical issues and the diagnoses and treatment provided. Furthermore, it reviews injury epidemiology and risk factors as well as considerations for the marathon medical field hospital and event medical plan.

1. 2014 CORK CITY MARATHON
CIAN O’BRIEN

2. OVERVIEW
Cork City Marathon Overview
Case Studies
Research
Event Medical Plan

3. WHAT IS A MARATHON?
It is named after the Greek Battle of Marathon
After the Greeks were victorious over the Persians at the Battle of
Marathon, they sent a runner to Athens with the news
The runner, ran the entire distance to Athens without stopping,
announced the victory, and then dropped dead, due to the physical
stress on his body
A marathon is an endurance foot race which covers 26 miles, 385 yards
(42.2 kilometers)

4. CORK CITY MARATHON
Full Marathon
• 26 miles 385 yards/42.195 km
• Full Association of International Marathons and Distances
Races
Half Marathon
• 21.1 km
Relay Event
Youth Team Relay
• Open to all 2nd level students who will be aged 16 years or
older on 2nd June 2014.

7. THE PHYSIOLOGY OF
MARATHON RUNNING
• Running a marathon has been viewed, and still is by many, as too
extreme to be healthy.
• Physical stress of running a marathon played some role in not
holding a women's Olympic marathon race until 1984
• It should be respected for the physiological stress inflicted over its
26.2 miles

8. Running a five-minute-per-mile marathon requires a
15-fold increase in energy production for over two hours
Runners who finish in over four hours maintain a
10-fold increase in their metabolism
Extended energy demands require the cardio, respiratory,
endocrine, and neuromuscular systems to operate at an elevated
level for an inordinate length of time

10. DIFFERENTIAL DIAGNOSIS
ABDOMINAL PAIN

11. CASE STUDY 1
John O Sullivan 39 year old
Bib Number 5025 (Full Marathon event)
Mile Marker – 14
Alerted by marathon volunteers
Chief Complaint – Disorientated
Vitals Signs
HR – 145 regular
BR – 34 fast
SP02 – 94%

12. 1 2
3

13. FINAL DIAGNOSIS IN
MEDICAL CENTRE

15. HYPERTHERMIA
• The heart helps control body temperature by pumping warm
blood to the skin where body heat is lost through the
evaporation of sweat
• During a marathon, heat loss and production can increase
over 10-fold
• High humidity and dehydration can make heat loss more
difficult
• High humidity levels reduce evaporation, while dehydration
impairs the ability to transfer heat from the muscles to the skin
• Either situation will increase body temperature and the risk for
heat problems

16. HYPERTHERMIA
• Muscle weakness and disorientation can develop with body
temperatures of 40 degrees Celsius,
• A loss of consciousness can occur with body temperatures
near 41.5 degrees Celsius

17. HYPERTHERMIA
• Hyperthermia, during marathon running can be due to
• Climate,
• Dehydration,
• High metabolic rate from running a faster-than-usual pace
• Marathon runners may overdress or not remove layers or
clothing as the air temperature rises over the course of the
marathon

18. HYPERTHERMIA
• The average sweat rate for runners is 1.2 liters
per hour
• Most runners either can't tolerate drinking that much or
choose not to drink that much liquid
• Typically, runners drink as little as 200 milliliters per hour
but rarely more than 1 liter per hour
• Therefore, it is not uncommon for runners to lose 2 to 10
% of their body weight through sweating

19. HYPERTHERMIA
• Towards the end of a marathon, when the
speed and effort of running increase, the
body becomes less efficient at using energy,
which produces more excess heat, which in
turn drives the body temperature even
higher

20. CASE STUDY 2
Ann Aherne 27 years old
Mile Marker 10.5
Bib Number 1141 (Half Marathon Event)
Alerted by marathon volunteers
Chief Complaint: disoriented, vomiting
Vital Signs
HR 168 regular
BR: 28 fast & Shallow
SP02 – 93%
Temp – 37.8

21. 1 2
3

22. FINAL DIAGNOSIS IN MEDICAL
CENTRE
Exercise-Associated

24. HYPONATREMIA

25. • A low sodium concentration in the blood
• <135mmol/L
• Sodium is an electrolyte that helps with nerve and muscle
function, and also helps to maintain BP.

27. HYDRATION STRATEGIES

28. HYPONATREMIA
• The major cause of hyponatremia = is drinking too much
water, which dilutes sodium levels in the blood
• Low sodium levels cause swelling or edema in the brain, which
can be fatal
Davis et al. (2001) found 26 cases of hyponatremia in over 34,000
runners from the 1998 and 1999 San Diego Rock 'n' Roll
Marathon
• They found that hyponatremia was
• greater in women
• slower runners (those who finish in over four hours)
• NSAIDs

29. Why women?
• Less water can dilute sodium levels in
smaller bodies
• Estrogen can further contribute to brain swelling
once it starts

30. Why slow runners?
• Slower runners are at a greater risk simply
because they have more time during a
marathon to drink too much water

31. Why NSAIDs?
• NSAIDs increase the effect of ADH
Which increases water retention

32. • Hyponatremia can develop after completion of a marathon
when
• Hormonal changes cause increases in absorption of water
• Sodium lost in the urine

33. DIAGNOSIS & TREATMENT

34. CASE STUDY 3
Sean Lynch 64 years old
Bib Number 18978
Mile Marker: Finish Line (Full Marathon)
Chief Complaint: Disorientated, Shivering &
Generally unwell
Vital Signs
HR – 68 regular
BR – 24 shallow
SP02 – un-recordable

36. 1 2
3

37. FINAL DIAGNOSIS IN MEDICAL
CENTRE

38. • Hypothermia can be the main environmental concern
for marathon runners
• The risk for hypothermia is greater in cold, windy, or wet
weather
• If the second half of the marathon is run slower than the first
half, not enough heat may be generated to maintain body
temperature
• Any sweat that builds up can saturate clothing, which will draw
additional heat away from the body

39. CASE STUDY 4
Sarah Boylan 21 years old
Bib Number: 705
Mile Marker: 18 (Relay Event Change Over Point)
Chief Complaint: Generally unwell, disorientated, nausea,
sweating, combatative
Vital Signs
HR – 102 irregular & weak
BR – 34 shallow & fast
SP02 – 92%

41. 1 2
3

42. FINAL DIAGNOSIS IN MEDICAL
CENTRE

43. • A blood sugar level <4.0mmol/L
• The brain prefers glucose as its
fuel
• Hypoglycemia impairs brain
functions

44. • May occur in Diabetic, or non diabetic runners
when not enough carbohydrates are consumed during the
race

45. GLYCOGEN DEPLETION
• Carbohydrates provide energy to the muscles faster than fats
• Inside the body, carbohydrates are found as glycogen in the
muscles and liver and as glucose in the blood
• As the amount of glucose in the blood is used up, the liver
converts its glycogen into glucose and releases it into the
bloodstream to maintain a constant supply of glucose to the
muscles

46. Signs & Symptoms may include,
• Altered mental state,
• Sweating,
• Fatigue,
• Tachycardia,
• Palpitations,
• Hunger,
• Headache
• Slurred speech.
• (Medical alert tag)

48. Treatment?

49. INJURY
30,000 - 50,000
steps to run a marathon
Every time the foot hits the ground, a stress three to four times
body weight is absorbed by the ankles, knees, hips, and lower
back

50. INJURY EPIDEMIOLOGY
Most common being knee pain, hamstring problems,
dehydration, blisters
The injury rate from 12 years of the Twin Cities Marathon was
2.1 percent of all runners (21.15 per 1,000 entrants), with the top
five injuries being:
Exercise-associated collapse 59.4 %
Blisters - 19.9 %
Muscle strain - 14.3 %
Muscle cramps - 6.1 %
Skin abrasions - 1.9 %

51. BLISTERS – 19.9%

54. MUSCLE STRAINS – 14.3%

55. FACTORS THAT INCREASE RISK
OF INJURY
• 1st marathon
• Participation in other sports
• Illness 2/52 prior
• Current use of medication
• Training mileage
Runners who train less than 60 kilometers per week were more
likely to become injured while running a marathon
Higher levels of training have been shown to decrease the risk
for knee injuries but increase the risk of injury to the
quadriceps and hamstrings during a marathon

56. ELITE RUNNERS

57. ELITE RUNNERS
Copenhagen Marathon found the most common problem in
elite runners was:
Gastrointestinal (GI) distress - 26 %
Back or joint pain - 20 %,
Muscle cramps -16 %
Blisters and other skin lesions - 16 %
Elite runners who suffer from GI distress secrete higher levels of
GI hormones or consume higher amounts of NSAIDs

58. CASE STUDY 4
• Paul Ahern 37 years old
• Bib Number 234
• Mile Marker 19
• Chief Complaint –
Collapse/unresponsive
• Agonal breathing, can’t
located pulse
• AMPLE – not available

60. 1 2
3

61. CARDIAC ARREST

68. How common is it really?

71. ✖ ✔

72. EXERCISE-ASSOCIATE
COLLAPSE

73. • A collapse in conscious runners who are unable
to stand or walk unaided, as a result of dizziness,
faintness or light headedness.
• This collapse usually occurs after a runner
stops exercising

74. EXERCISE ASSOCIATED
COLLAPSE
• This happens because during exercise the muscles of the
lower limbs require an increased blood flow. These
muscles then act like a ‘second heart’ ensuring that this
blood is returned to the heart assisted by the contraction
of the leg muscles.
• When a runner suddenly stops exercising (e.g. finish line)
the body’s ‘second heart’ stops functioning and blood
pools in the legs, inducing exercise associated collapse.

75. EXERCISE ASSOCIATED
COLLAPSE
• EAC is the most common condition seen at finish line medical
tents
• Signs & Symptoms of EAC include:
• Abnormal body temp
• Altered mental state,
• Altered LOC,
• CNS changes
• Ambulation problems
• Muscle spasms
• Tachycardia
• Vomiting/Diarrhoea

76. • Before treating EAC attention must be focused on ruling
out other causes of collapse by performing:
• Vital Signs
• BSL
• ECG
• Blood tests
• Rectal Temp
• AMPLE history
• Treatment of EAC involves fluid redistribution and
replacement in the body to improve cerebral and vital organ
perfusion.

77. • The redistribution of blood in the body is assisted by the
positioning of the patient.
• With symptoms improving in 5-30 minutes.
• Trendelenburg Position

78. DISCHARGE CRITERIA FOR
RUNNERS
Normal Mental Status/ GCS 15/15
‘Normal’ Vital Signs
Ability to mobilise
Carry out a ‘sit-test’
Warm dry clothing
Discharged to a responsible adult
Diet and hydration advice and ED/GP follow as required

79. OTHER RUNNING INJURIES TO
CONSIDER
Runners Nipple
Stress Fractures
Sprains & Strains RICE
Lung Injury
Exercise Associated Muscle Cramps
Blisters/Cuts/Grazes

80. MARATHON FIELD HOSPITAL

85. WHERE WE’VE COME FROM?

86. WHERE WE ARE GOING…
• Following international best practice we will continue to
develop the service we provide.
• Carrying out Research
• Providing Evidence Based Practice
• Looking outside the box.
• Becoming affiliated with the International Marathon
Medical Directors Association.

87. RESEARCHER – CIAN O’BRIEN

88. The Epidemiology of Illness and Injury at the 2014
Cork City Marathon (O’Brien et al, 2015)

89. Questions?
Nothing too hard,
please!

90. MEDICAL EVENT PLAN

91. QUESTIONS