Dr. Gary Mak 麥耀光 - University of Macau | The only ... and CV impac… · Cardiovascular Adaptations to ... Blood volume increases, as does red cell volume, but ... Endurance

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Dr. Gary Mak 麥耀光心臟科專科醫生

President of HK Association of Sports Medicine and Sports Science

Director of Pro-Cardio Heart Disease and

Stroke Prevention center

Consultant Cardiologist HK Sports Institute

Cardiovascular Impacts of Endurance Exercise: Benefits or Injuries

www.hkasmss.org.hk

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http://www.facebook.com/hkmarathon#

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Rugby 7

HK Golf Open 2014

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2012 Para-Olympic CV screening

BENEFIT OF EXERCISERegular exercise extends 7 years of life expectancy

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American Society of Hypertension (ASH) 2013 Scientific Sessions

• Dr Michael Doumas (VA Medical Center) examined the benefits of exercise in 2077.

• Hypertensive men 70 years of age and older.

• Average follow-up: nine years.

• Peak workload was estimated in metabolic equivalents (METs) – low aerobic fitness, METs <4.5 (n=685): reference

– moderate aerobic fitness, METs 4.6-6.5, (n=786)

• 15% lower mortality (HR 0.85; p=0.024)

– high aerobic fitness, METs >6.5, (n=606)

• 37% lower mortality (HR 0.63; p<0.001)

• For every 1-MET increase in exercise capacity, the risk of all-cause mortality was reduced by 8% (hazard ratio [HR] 0.92; p<0.001).

Never too old to get moving:Aerobic fitness lowers risk of death in elderly

Exercise Intensity (monthly TRIMP)

CV response to exercise: U-curve Response!

The more is NOT better

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Mayo Clin Proc. 2012;87(6):587-595

American College of Sports Medicine (ACSM) 2012 Annual MeetingDr Duck-chul Lee (University of South Carolina, Columbia).

Aerobics Center Longitudinal Study (ACLS)Running linked with a 19% lower risk of death

N > 52,000, F/U 20 years

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Sinus Rhythm Atrial Fibrillation400 bpm

100 – 150 bpm

Atrial Fibrillation 心房顫動LV hypertrophy in Athletes ↑ atrial

stretch

P No P

EDITORIALEur Heart J, July 24,2015

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ANS Response to Endurance Exercise

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Vascular Tone(BP)

HR

Autonomic Nervous System

α

β

Cortisol

Cathecholamine

Blood Volume

ALDOSTERONE

ADH

Lahiri, M. K. et al. J Am Coll Cardiol 2008;51:1725-1733

Autonomic Nervous System&

Cardiovascular Response

HR

HR

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RR Interval – Inversely Related to HRNormally all would shortened as HR increases

Heart Rate variability (HRV) : beat-to-beat variations in HR

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HR recovery during cool down period:An indicator of ANS balance

Vagal Reactivation




Regular Endurance training=>Enhanced Vagal Modulation

↓resting HR

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Excessive intensive exerciseOr overtraining =>

Sympathetic predominance

Endurance training leads to heart (LV) enlargement

Dynamic-Power + output

Static-Power

LV volume LV mass

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Eccentric Hypertrophy increases Stroke Volumes and cardiac output

Subjects SV Rest SV Max

Untrained 50‐70ml 80‐110ml

Trained 70‐90 110‐150

Highly Trained 90‐110 150‐220

Cardiac Output = Stroke Volume x Heart Rate

Endurance Training

α

β

Cortisol

Cathecholamine

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Cardiovascular Adaptations to Endurance Training

Left ventricle size and wall thickness increase.

Resting, submaximal, and maximal stroke volume increases.

Maximal heart rate stays the same or decreases.

Blood volume increases, as does red cell volume, but to a lesser extent.

Cardiac output is better distributed to active muscles and maximal cardiac output increases.

Resting blood pressure does not change or decreases slightly, while blood pressure during submaximal exercise decreases.

M/41, former Olympic triathlon, with regular training and competition.

Stopped training for 3 weeks after Sebaceous Cyst excision. Developed fast HR (105 bpm) and high BP (140/100 mmHg)

Seen by Endocrinologist: Thyroid function - normalPhaeochromocytoma - unlikely

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He had a second operation for thyroid nodule one week later

HR was found to be back to 50 bpm in the middle of operation

He had a second operation for thyroid nodule one week later

HR was found to be back to 50 bpm in the middle of operation

500 ml saline

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Biokinetic Swim Bench and Strength ChangesDetraining

a b

Physiological effects of 2‐4 weeks of DETRAINING

• VO2 max: down 4‐15%

• Blood volume: down 5‐10% (within 2 days)

• Stroke volume: down 6‐12%

• Heart rate: up 5‐10%

• BP: up 5‐10%

• Flexibility: Decreases

• Lactate threshold: Decreases

• Muscle glycogen levels: down 20‐30%

• Aerobic enzyme activity: Decreases

VO2 = SV x HR x a‐v O2 diff

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Maintenance Training is ImportantThe negative effect of detraining is rapid (in less than 2 week)

The recovery from retraining is slow (well over 20 weeks)!!!

EK

45 yo male badminton coach• Recurrent palpitation, mostly at night

• Seldom have attacks during exercise.

• ECG: paroxysmal atrial fibrillation,

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Meta-analysis of the risk to develop atrial fibrillationcomparing athletes with the general population

Abdulla J et al. Europace 2009; 11: 1156-1159

AF is 5 times more common in athletes

EDITORIALEur Heart J, July 24,2014

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Marathon runningThe legend, 490 BC

22 miles run from the plains of Marathon to the city of Athens to report the victory of the Athenian army over the Persians. Upon his arrival, Pheidippedes exclaimed “Rejoice,

we conquer” and drop dead.

Marathon running- a slow roasting

• Hyperthermia:– 15X fold in heat production

• Hypothermia: - heat loss increase of 10 to 25 times

• Dehydration / Water intoxication• Glycogen depletion / hypoglycemia

– “ bonking” or “hitting the wall”: – depletion of 30 km worth glycogen

• Injuries (40 km takes 30,000 - 50,000 steps)• Upper respiratory tract infection / asthma

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Exercise Induced C-Troponin Elevation

心肌酶指數是其中一種可界定急性心臟病發的指標之一

右心室功能受損, 左心室功能正常

右心室左心室

受損

正常

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Myocardial Fibrosis (Scarring) on MRI

5/40 (12.5%) had evidence of permanent damag

Kim et al N Engl J Med 2012;366:130-40.

• Marathons vs half-marathons (1.01 vs 0.27per 100,000) • Men vs women (0.90 vs 0.16per 100,000) • Male marathon runners death rate increased 2 times in last 5 years• 2000–2004: 0.71 per 100,000 • 2005–2010: 2.03 per 100,000• older participants (>40 years), increase from 26% to 46%, from year

2000 to 2009

High Risk Group: Middle aged males that attempt full Marathon

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Marathon Participants in recent years • Minority

– Elite Sportsman /club runners

• Majority

– 40s and 50s

– Major Cardiovascular risk factors

• Smokers, DM, HT, High cholesterol

• History of heart disease or stroke

– Survivors of cancer

Risk in relation to running Time

Low Risk : Elite Club Runners,

<3 hours

High Risk: Middle Aged (esp. male), Runners

3‐4 hrs

Low risk: Costumes,

5 hrs+

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Competitive Sports Increase Risk:Effect of Adrenaline!

Final Miles:=5% of total running distance=50% of deaths

跑手們在比賽中應保持自己的速度，抱著旨在參與的態度享受過程。避免因追求速度及名次為身體帶來額外的壓力。

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Pre-participation EvaluationProper training and preparation

Adequate rest and recovery

Exercise and Heart: Benefit or Injury?

101 years old Marathon Runner

London Marathon 2012:First 101 years-old finisher,Mr. Fauja Singh (7:49 hrs)

Toronto Marathon 2011

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The Risk Continuum

AGE CV RISKEXERCISEINTENSITY

HABITUALEXERCISE

RISK OF SCD

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Major cause of SCD: < 35 years old – Hypertropic

cardiomyopathy (HCM)> 35 years old – coronary artery diseases

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www.hkasmss.org.hk

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The International Olympic Committee (IOC) has recommended—but not mandated—that all countries screen their athletes to minimize the risk of sudden death. According to the IOC, if the 12-lead ECG raises suspicion of an underlying serious problem in an athlete, further tests should be performed. In many screening programs, the workup also includes an echocardiogram…. London, 2012.

fifapcmaform.pdf

PCMAPre-Competition Medical Assessment

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Conclusion • Exercise related Sudden Cardiac Arrest (SCA) are not infrequent and are

potentially preventable. They are usually related to congenital or structural abnormalities in younger than 35 and coronary artery disease in those 35 years and above.

• The combination of carefully conducted history and examination (according to the 12‐element AHA recommendations) and 12‐lead resting ECG are generally effective screening protocols.

• The additional use of echocardiograms in the younger athletes (<35 years of age) and the low radiation dose Coronary CT Angiography in the old athletes (>35 years of age) are sensitive and specific in identify those at risk of exercise related sudden cardiac arrest.(SCA) .

• Pre‐participation Evaluation are recommended for high intensity competitive athletes especially the elite and professional athletes where resources are usually available.

以心為心

www.hkasmss.org.hk

www.pro-cardio.com

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Dr. Gary Mak 麥耀光 - University of Macau | The only ... and CV impac… · Cardiovascular Adaptations to ... Blood volume increases, as does red cell volume, but ... Endurance