Cyclists' hearts: Why elite cyclists die in their sleep (7 min video)

[medlifecrisis]

Thanks everyone! Really nice to read the kind comments and sorry I missed the discussion.

For those that can't watch (I'd understand, I can't stand hearing my voice!) don't worry - your low resting heart rate is a good thing. The twist to this story which I didn't want to mention in advance is performance-enhancing drugs, specifically EPO. EPO increases your red cell count making your blood thicker. This can occur in people who move to high altitude, smokers or people with lung disease (ie all get lower oxygen than normal) and is called polycythaemia. It can predispose the person to clots forming but isn't a HUGE risk as most people's hearts are within 60-100bpm.

However, combine it with crazily low heart rates found in elite athletes and it can be a recipe for disaster. The reason they die in their sleep is that's when the basal metabolic rate drops lowest.

A few responses to people:

• "Am I going to die?" - I guarantee it. But hopefully not for many years

• Footballers dying while playing - absolutely, another tragic cause of young deaths. However this is normally due to inherited conditions like hypertrophic cardiomyopathy (leading cause of death in athletes under 40), abnormal rhythm problems (Fabrice Muamba) or other structural and electrical problems (James Taylor (cricket)). All of these can be exacerbated by exercise, hence they tend to die/have a cardiac arrest while playing.

• Resting heart rate I would normally take to mean HR while awake, at rest. Not while asleep - don't listen to those lying Fitbits which flatter you! Time it yourself over 30 seconds or so. I recommend everyone to track it (once a month is fine but obviously the quantified self and wearables has exploded) and assess response to exercise.

Fire away with any other queries and thanks again!

 

[Levo-Lon]

Bell on the toes..simples out and a fire extinguisher..Times have changed

 

[Ajax Bay]

Enjoyed watching the video @medlifecrisis

I can ride for an hour with a 182 average, maxing at 202. Can rarely get it lower than about 170 when on the bike, even when riding casually. That’s using Garmin chest strap. Is this stupidly high?

Those data are out of the ordinary, particularly for bike riding. Stupid? No. It's what your body does.

So theoretical max = 220 - age

That formula is widely discredited - in fact the doctor who mooted it has explicitly said that it is (I paraphrase) useless, particularly for active/fit people. Precis:
Devised in 1970 [Haskell&Fox] . . . it was based on data from [other studies] but gained widespread use through being used by Polar Electro in its heart rate monitors, which Dr. Haskell has "laughed about",[23] as the formula "was never supposed to be an absolute guide to rule people's training." It's easy to remember and calculate but is a poor predictor of HRmax - it has a large inherent error so has neither the accuracy nor the scientific merit for use in exercise physiology and related fields.[24]
Nes et al (2012) found the best fit to be HRmax = 211 − (0.64 × age) with a 10 beat standard deviation (and you can do a few km on the road while you work that out).

 

[bpsmith]

Just watched the video now @medlifecrisis. I find some YouTube videos very annoying for no apparent reason other than peoples voice.

Your voice certainly doesn’t fall into that bracket I hasten to add.

Very interesting video in fairness and, as mentioned already, I liked the humour at the end too.

My thumbs up takes you to 500. Subscribed too. Keep them coming.

 

[Slick]

Just watched the video now @medlifecrisis. I find some YouTube videos very annoying for no apparent reason other than peoples voice.

Your voice certainly doesn’t fall into that bracket I hasten to add.

Very interesting video in fairness and, as mentioned already, I liked the humour at the end too.

My thumbs up takes you to 500. Subscribed too. Keep them coming.

So did I, but only because I fancied my chances on that road race he mentioned.

 

[Alan O]

...the best fit to be HRmax = 211 − (0.64 × age) with a 10 beat standard deviation.

Interesting. The 220-age one gives Max HR of 161 for me, which isn't that close as in reality my HR can get up to around 180. The 211 − (0.64 × age) one gives 173, so that fits me quite well.

 

[bpsmith]

So did I, but only because I fancied my chances on that road race he mentioned.

I think he’s sharking tbh. His resting HR is ultra low, so I reckon he’s faster than he makes out.

 

[Slick]

I think he’s sharking tbh. His resting HR is ultra low, so I reckon he’s faster than he makes out.

 

[GrumpyGregry]

Thus far, and you've had a good innings.

I wonder if anyone has ever died at parkrun when determining their max HR from the 100 metres whilst going for a SB/PB?

 

[Colin_P]

I wonder if anyone has ever died at parkrun when determining their max HR from the 100 metres whilst going for a SB/PB?

No, not there doing that but I've died quite a few times in other intersting and not so interesting circumstances, all from cardiac arrest, and it ain't very nice.

Twice in bed
Once while driving
Once in an ambulance
Once whilst making bacon sandwiches for the family on a Sunday morning
Once on the sofa whilst watching the One show
and
About four times in A&E.

All due to a viral infection from many years before which scarred my heart muscle but unknown to me at the time. All was well until I overdid the training over a period of about a month which I'm convinced tipped things over the edge.

Be careful you lot, just because you can doesn't mean you should red-line your heart rate!

The other elite cyclist common heart condition is Atrial Fibrillation which can be quite nasty especially when it goes on to cause a stroke. (P.S. I've never been and never will be an elite cyclist).

Again, be careful and again just because you can doesn't mean you should. Build up slowly and don't go mad. Although not terribly scientific, the 220-age thing should be viewed as an absolute upper limit, not a target of barrier that should be broken unless you are a nutter.

A cardiac arrest is very sudden and most don't come back from them but for those nutters out there they are the ultimate KOM !

 

[jefmcg]

No, not there doing that but I've died quite a few times in other intersting and not so interesting circumstances, all from cardiac arrest, and it ain't very nice.

Twice in bed
Once while driving
Once in an ambulance
Once whilst making bacon sandwiches for the family on a Sunday morning
Once on the sofa whilst watching the One show
and
About four times in A&E.

OK. I'm calling shenanigans, because you are claiming to have survived 5 events each with a 18.5% chance of surviving and 5 more with a 26% chance of leaving hospital alive, which means your chances of being here to share that with us are 0.00003%.

How many medical journals have featured your case study?

 

[classic33]

@medlifecrisis, worth a read?
http://www.thecormactrust.com/sudden-cardiac-death-ireland/

Edit to ask have you included height in your study?

 

[Colin_P]

OK. I'm calling shenanigans, because you are claiming to have survived 5 events each with a 18.5% chance of surviving and 5 more with a 26% chance of leaving hospital alive, which means your chances of being here to share that with us are 0.00003%.

How many medical journals have featured your case study?

Because Implanted Cardioverter Defibrillator.

[edit] just the one medical journal

 

[Slick]

OK. I'm calling shenanigans, because you are claiming to have survived 5 events each with a 18.5% chance of surviving and 5 more with a 26% chance of leaving hospital alive, which means your chances of being here to share that with us are 0.00003%.

How many medical journals have featured your case study?

I hate it when maths and facts get in the way of a good story.

 

[Slick]

Because Implanted Cardioverter Defibrillator.

[edit] just the one medical journal

Scary stuff.