ANOTHER Mountain Biker Dies!
In article ,
Rick Hopkins says...
On Feb 7, 9:24=C2=A0am, Mike Vandeman wrote:
SNIP
All of what you are saying is pure speculation -- what passes for
thought among mountain bikers. The point is that mountain biking is
touted as "healthful", when it's not. Those claims don't take into
consideration the large probability that you will be seriously injured
or DIE. For 261+ examples, seehttp://mjvande.nfshost.com/mtb_dangerous.ht=
m.
On the other hand, most people who hike NEVER have any injury or heart
attack. Walking provides better exercise with far less danger --
something that mountain bikers keep trying to sweep under the rug.
Pure speculation regarding a cardiac event. That is truly laughable.
The entire medical profession disagrees with you as it relates to the
increased likelihood of a cardiac event. See some of the exerts
below. It is rather technical and likely too much for your tiny
brain, but in plain English, what it concludes is that individuals
that have heart conditions are more susceptible to to cardiac
incidents when engaging in strenuous exercises - the type of exercise
is not particularly germane for this analysis (are you at risk of a
heart attack or not), simply does it elevate heart rate and stress the
heart - they use jogging as the standard to determine the minimum
amount of work load. It also concludes that healthy individuals with
no genetic predisposition to heart disease or evidence of heart
disease, reduce their low risk even lower by regular exercise that
stresses the heart. They also conclude that those individuals that
have some risk or are in poor shape, to only undertake activity under
the supervision of their doctor, and by doing so even they will
eventually reduce their risk of a cardiac event. So healthy
individuals (such as myself - 58 years old, no family history of heart
disease, 172 lbs, 6'3" 9.5 to 10% body fat, engage in 9 to 14 hrs of
aerobic activity per week including speed skating, cycling, running,
hiking and dryland training, plus 4 to 6 hrs of strength training and
stretching) who continue to engage in activities that put a load on
the heart (I regular push my HR between 170 to 180 for a few minutes
at a time each week and easily maintain 150-155 on 30 to 60 minute
climbs) are extremely unlikely to suffer a cardiac event while
exercising. Individuals of poor fitness and/or history of heart
disease put themselves at increased risk, unless they cautiously
approach a regular exercise program set up by their doctor. Ask Jim
Fixx the runner who is best know for writing The Complete Book of
Running, who died of a heart attack while running - he had a previous
diagnosed heart condition and he mistakenly thought running would cure
it. Healthy runners, cyclist (road and mt), skaters, cross country
skiers, etc. maintain their risk of a heart event as very low if they
continue their activity.
AHA Scientific Statement
Exercise and Acute Cardiovascular Events
Placing the Risks Into Perspective: A Scientific Statement From the
American Heart Association Council on Nutrition, Physical Activity,
and Metabolism and the Council on Clinical Cardiology
In Collaboration With the American College of Sports Medicine;
Paul D. Thompson, MD, FAHA, Co-Chair;
Barry A. Franklin, PhD, FAHA, Co-Chair;
Gary J. Balady, MD, FAHA;
Steven N. Blair, PED, FAHA;
Domenico Corrado, MD, PhD;
N.A. Mark Estes III, MD, FAHA;
Janet E. Fulton, PhD;
Neil F. Gordon, MD, PhD, MPH;
William L. Haskell, PhD, FAHA;
Mark S. Link, MD;
Barry J. Maron, MD;
Murray A. Mittleman, MD, FAHA;
Antonio Pelliccia, MD;
Nanette K. Wenger, MD, FAHA;
Stefan N. Willich, MD, FAHA;
Fernando Costa, MD, FAHA
a few exerts:
High-Risk Activities
Few systematic studies have identified high-risk activities, again
because of the rarity of exercise-related cardiovascular events. In
general, the risk of any vigorous physical activity is an interaction
of the exercise per se and the individual=E2=80=99s physical fitness becaus=
e
identical physical tasks evoke lower cardiac demands in physically fit
subjects than in unfit persons. Snow shoveling has repeatedly been
associated with increased cardiovascular events,44,45 probably because
it can elicit higher rate-pressure products than does treadmill
exercise testing,46 because it is often performed out of necessity by
unfit individuals, and because some cardiac patients develop angina at
lower rate-pressure products, suggesting a coronary vasoconstrictor
response, during exercise in cold temperatures.47
Strategies to Reduce Exercise-Related Cardiovascular Events
No strategies have been adequately studied to evaluate their ability
to reduce exercise-related acute cardiovascular events. Physicians
should not overestimate the risks of exercise because the benefits of
habitual physical activity substantially outweigh the risks. From
observational studies,4 it appears that one of the most important
defenses against exercise-related cardiovascular events in adults is
to maintain physical fitness via regular physical activity because a
disproportionate number of exercise events occur in the least
physically active subjects performing unaccustomed vigorous physical
activity.5,6,32 Several strategies to reduce events appear prudent
although unproven. These include the following: preparticipation
screening, excluding high-risk patients from some activities,
reporting and evaluating prodromal symptoms, preparing fitness
personnel and facilities for cardiovascular emergencies, and
recommending prudent exercise programs. Each of these is discussed
below.
Preparticipation Screening
Young Athletes
The American Heart Association (AHA) recommends cardiovascular
screening for high school and college athletes before athletic
participation and at 2- to 4-year intervals.48,49 The examination
should include a personal and family history and a physical
examination focused on detecting conditions associated with exercise-
related events.48 The AHA does not recommend routine, additional
noninvasive testing such as a routine ECG. The omission of routine
noninvasive testing is controversial because the Study Group on Sports
Cardiology of the European Society of Cardiology has recommended that
routine ECGs be obtained on all athletes as part of a preparticipation
evaluation.50
The European recommendation is based largely on an observational study
performed in the Veneto region of Italy.51 Italy has mandated the
preparticipation screening of athletes, including an ECG, since 1982.
The annual incidence of sudden death among athletes 12 to 35 years of
age decreased 89% with screening, from 3.6 deaths to 0.4 deaths per
100 000 athletes. There was no change in deaths among nonathletes,
which suggests that screening mediated the decrease. These results
provide the best evidence to date in support of the preparticipation
screening of athletes but have several limitations.52 The study did
not directly compare the screening and nonscreening of athletes but
was a population-based, observational study. Other changes in the
management of the athletes could have contributed to the improvement.
In addition, the study did not directly compare screening performed
with and without an ECG. Finally, there could be small differences in
the screened and comparison populations because the athletes were
screened at the Padua Center for Sports Medicine, whereas the
comparison population consisted of subjects from the larger Veneto
region.
Healthy Adults
Although no data from controlled trials are available to guide the use
of exercise testing in asymptomatic adults without known or suspected
CAD before beginning an exercise training program, the writing groups
from the American College of Cardiology (ACC)/AHA Guidelines on
Exercise Testing53 and the American College of Sports Medicine
(ACSM)54 have addressed this important issue by consensus. Although
each group provides slightly different specific recommendations (see
Table 4), the main theme of these recommendations is unified and
clear: Individuals who appear to be at greater risk of having
underlying CAD should be considered for exercise testing before
beginning a vigorous (=E2=89=A560% V=CC=87o2 reserve) exercise training pro=
gram
(where V=CC=87o2 reserve=3Dpercent intensity=C3=97[V=CC=87o2 peak=E2=88=92V=
=CC=87o2 rest]+V=CC=87o2
rest). This is particularly evident in that both groups recommend
exercise testing before exercise training for patients with diabetes
mellitus. In contrast, the US Preventive Services Task Force (USPSTF)
states that insufficient evidence exists to determine the benefits and
harm of exercise stress testing before exercise programs.55
View this table:
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TABLE 4. ACC/AHA, ACSM, and USPSTF Recommendations for Exercise
Testing Before Exercise Training
A major limitation of exercise testing is that =E2=80=9Cpositive=E2=80=9D e=
xercise
test results require the presence of a flow-limiting coronary lesion,
whereas most acute cardiac events in previously asymptomatic subjects
are due to vulnerable plaque disruption. Consequently, an exercise
stress test with or without imaging can be normal despite the presence
of coronary plaque that may rupture. This requires that health
professionals evaluate the entire atherosclerotic risk profile in
patients when advising on the feasibility of a vigorous exercise
program.
Recommending Prudent Exercise Programs
Ostensibly healthy adults without known cardiac disease should be
encouraged to develop gradually progressive exercise regimens. Because
the least fit individuals are at greatest risk for exercise-related
events, gradually progressive programs should theoretically increase
fitness and reduce acute CAD events without excessive risk. Patients
with known cardiac disease also should be counseled to include at
least 5 minutes each of warm-up and cool-down in their exercise
training sessions to reduce the likelihood of inducing cardiac
ischemia with sudden, intense physical effort62,63 and to avoid the
decrease in central blood volume that can occur with the abrupt
cessation of physical activity. Patients with cardiovascular disease
who are interested in participating in competitive sports should be
evaluated and advised in accordance with the 36th Bethesda Conference
guidelines.56 Physically inactive individuals and patients with known
cardiovascular disease should avoid strenuous, unaccustomed exercise
in both excessively cold and hot environmental conditions. Vigorous
exercise in the cold such as snow shoveling has repeatedly been
associated with acute cardiovascular events,44,45,64 and hot, humid
environments require an increased heart rate response to handle the
increased thermal load.65 Increased altitude reduces oxygen
availability and augments the cardiorespiratory and hemodynamic
responses to a given submaximal work rate, thereby increasing cardiac
demands. Individuals exercising at altitudes of 1500 m should limit
the intensity of their exercise until acclimatized.54,66
The long and short of is, if you are healthy continue to exercise (and
yes mt biking is no more or less strenuous from a heart perceptive
then triathlons, road cycling, speed skating, cross country skiing,
inline skating, tennis, soccer, basketball, swimming running, etc.),
however, if you have a heart condition, then work with your doctor and
maybe you may need to stay away from the more strenuous sports. So in
conclusion, mt biking does not put people at greater risk (or lesser)
of a cardiac event then the myriad of other sports that are equally
strenuous. That is not speculation and is presently well accepted in
the medical profession.
Enjoy,
Rick
Rick: Will you PLEASE stop cluttering up this thread with facts.
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