I just thought I'd point to this - Is exercise to blame for Andrew Marr's stroke?
Marr is a fairly high profile journalist / TV presenter in the UK. He suffered a stroke a few months ago that he is now blaming on interval training on the Concept 2.
As usual, the NHS piece is pretty balanced, although it is a little concerning the way in which the medics talk about the potential dangers of interval training:
Maybe there was more to it though:
Marr is a fairly high profile journalist / TV presenter in the UK. He suffered a stroke a few months ago that he is now blaming on interval training on the Concept 2.
Marr said he had followed the advice to "take very intensive exercise in short bursts – and that's the way to health … I went on a rowing machine and gave it everything I had, and had a strange feeling afterwards – a blinding headache, and flashes of light – served out the family meal, went to bed, [then] woke up the next morning lying on the floor unable to move".
As usual, the NHS piece is pretty balanced, although it is a little concerning the way in which the medics talk about the potential dangers of interval training:
"Regular exercise is an important factor in stroke prevention and recovery. We have heard anecdotally that some activities like vigorous exercise can sometimes cause blood vessels to burst. We need more research on the underlying factors that might make that happen.
"We do know that high blood pressure itself is the single biggest cause of stroke. Until more research is done on specific triggers, we'd suggest getting your blood pressure checked and taking steps to keep it under control – exercise can help with that."
Maybe there was more to it though:
Despite the media emphasis on the stroke risk exercise could pose, it should also be borne in mind that Andrew Marr has said that he had been "heavily overworked". Stress is a known risk factor for high blood pressure, and it is possible that this may have played a part in his condition.
Comments
"And what I'd done, I'd torn the carotid artery, which takes blood into the brain, and had a stroke overnight - which basically wipes out a bit of your brain."
Intensity of exercise is very subjective therefore TRAIN DON'T STRAIN.
This reminds me. About 10 years ago, people started dying coming of a ride in Disney World, Mission Space, I believe. I had done it, was convinced I was going to die, so I became aware of every news report about it. People had undiagnosed weaknesses in the brain, get subjected to G forces, then have embolisms and die coming off the ride.
Sure, there's a warning, but how many people check their brain out before going on vacation? The analogy is jumping into an extreme workout without considering other stresses, prior history, undiagnosed etc.
They are used by the film industry when the actor wants too much money and they need to replace him without shooting any new material from episode to episode.
And they are rare, but real.
It is good to be cautious but we can't really make any conclusions in this case, too many variables.
Some medical insights. This person had a carotid artery dissection. Arteries are arranged in 3 layers. A dissection occurs when the middle layer separates from the inner layer. Blood pulsing between these layers can propagate the tear (sort of like a log-splitter). This is especially true later after the blood in the dissection clots. If the dissection of a neck artery propagates far enough, it can cause stroke.
Of all the carotid artery dissections I have seen they were all caused by either the shoulder harness of a seat belt producing shear force on the neck during a car wreck, or whiplash injury/chiropractic adjustment. It is very rare for this to occur due to exertion and increased rate-pressure product (the heart rate x blood pressure).
If this person developed symptoms immediately after rowing, it is likely the dissection was pre-existing and the increased rate-pressure product caused propagation toward the brain. If it occurred because of his rowing, it is more likely due to some whiplash type motion at the neck during the rowing rather than increased BP.
With regard to traditional strokes (especially hemorrhagic) or leaking aneurysms, these are very unlikely to be triggered by exertion (even extreme exertion). The reason is that cerebral perfusion is autoregulated. The pressure that the brain sees is stable across a broad range of blood pressures. If mean arterial pressure is anywhere between 90 and 240, cerebral pressure remains constant at about 100-110.
The above explains why I like force-controlled weight lifting to achieve an interval effect. The more intense it goes, the lower the forces become (as you are getting weaker). On a rower or other aerobic piece, to get higher intensity the forces go up, as does the flailing (like neck whipping on a rower).
These sort of lay articles impart little useful information, and much confusion.
That is really helpful. Thanks
HIIT can be great, but it can also be done stupidly.
I remember thinking this whilst writing my review of the BBC program 'The Truth about Exercise' (on my blog); take an unfit person and make them do Tabata's. It just seems like a recipe for injury, or worse.
yours,
George
I agree. Just not for the reasons traditionally cited (although those contribute to some degree).