Machka 

A couple interesting articles ...

How exercise in old age prevents the immune system from declining - BBC News
How exercise in old age prevents the immune system from declining
Doing lots of exercise in older age can prevent the immune system from declining and protect people against infections, scientists say.
They followed 125 long-distance cyclists, some now in their 80s, and found they had the immune systems of 20-year-olds.
(Read article for more ...)

https://www.theguardian.com/lifeands...ng-study-finds
Cycling keeps your immune system young, study finds
Cycling can hold back the effects of ageing and rejuvenate the immune system, a study has found.
Scientists carried out tests on 125 amateur cyclists aged 55 to 79 and compared them with healthy adults from a wide age group who did not exercise regularly.
The findings, outlined in two papers in the journal Aging Cell, showed that the cyclists preserved muscle mass and strength with age while maintaining stable levels of body fat and cholesterol. In men, testosterone levels remained high.
More surprisingly, the anti-ageing effects of cycling appeared to extend to the immune system.
(Read article for more ...)


https://www.newscientist.com/article...16-GLOBAL-hoot
Cycling in later life makes you less likely to have a bad fall

This is a "subscriber" article, but they've also got a video on Facebook which basically indicates that cycling helps people with their balance.

Machka 

Just from my own personal experience, I find that doing the Century-A-Month challenge is a great way to remain fit and feel good throughout the year.

CliffordK

I think there is a growing body of evidence that cycling is protective in many ways.

When does one get into years spent sitting the bike saddle. Perhaps it is like putting those years into the bank for later withdrawal

unterhausen

I'm too lazy to read, wasn't the 125 cyclist study mostly randonneurs?

antimonysarah

Flounce

Cycling or any physical activity done in lieu of sitting on the couch or in front of a computer munching fatty snacks, is going to be much better for your health. Having said that, there is a tipping point - surpassed fairly quickly by our rando standards - beyond which we are likely making ourselves less healthy in the long run.

There is a significant body of evidence supporting the correlation between endurance sports and cardiac arrythmia later in life, namely atrial flutter.

https://www.velopress.com/books/the-haywire-heart/

I read this book, which is written by Lennard Zinn, former member of US National Racing Team, who many of us know as the author of "Zinn and The Art of Road Bike Maintenance"; and a cardiac electrophysiologist (cardiologist specializing in rhythm disorders) who is a triathlete as well.

As a physician whose father had Atrial Flutter treated with cardiac ablation, I found the evidence presented to be compelling and I am - speaking for myself - convinced that endurance sports significantly increase the risk of A-Flutter later on in life, even as it confers benefits in other areas. It doesn't mean we must stop riding, but we just need to accept the fact that like other activities that people enjoy that have health risks that can kill you, long distance cycling - compared to regular non-long-distance cycling - may actually make some of our lives shorter, not longer.

Osteoporosis leading to hip fractures in older cyclists is another phenomenon that has been well-documented, and adding a weight training program to a long distance cycling habit has *not* been shown to be protective. So if you ride until you are older, be careful. At a certain age, the risk of comorbidity from recovering from a hip fracture (DVT, pulmonary embolism, pneumonia, etc) is not small thing.

WNCGoater

I've heard or read various similar reports. My question is, what exactly is the definition of long distance cycling? Not arguing, just that seems a bit of an arbitrary statement yet as I stated, I've heard it before but never heard it defined.
So is "long distance cycling" defined as 40 miles three times a week or 100 miles once a week, or 120-200 miles once a month with multiple weekly 40 mile rides, or what? Is riding 30 miles 5 days a week the same as riding 75 miles twice a week?

Flounce

As I recall - and I no longer have the book - the science indicates an association between endurance sports and lone atrial flutter, and that there is likely a *threshold* for increased risk, but there are not enough studies to define what that threshold is.

For example - just googling the topic right now - one study found increased risk in people with over 1500 lifetime hours of sports activity. That doesn't mean that someone with 1000 lifetime hours is not at increased risk. Another study used 3 hours sports per week for at least 2 years as a criteria and found an increased risk. That doesn't mean that if you have less than 3 hours per week than you are not at increased risk. Yet another study used as its subjects the Swiss national cycling team from a given year in the distant past, which doesn't mean that if you are an amateur athlete but not on the Swiss team then you will not have increased risk.

unterhausen

I think the idea that cyclists aren't going to have heart problems like their age cohort is only partly true. And we have extra problems. I can think of 3 randonneurs who died from heart issues. Given my family history, sitting on a couch is really just waiting to die, and asking for a lot of other health problems before that. So I figure I should go out and make the best of it.

Happy Feet

I work in an extended care facility and have learned that there is no point worrying about things. If one ailment doesn't get you something else will.

I just try to live reasonably healthy and enjoy the exposure to life my activities give me. In fact, that's how I choose most of my interests; by the view of life they offer. In that regard cycling is pretty positive.

McBTC

Owner of a local 'cyclery' since the 70s had a heart attack at age 54 while riding on a week's club meet-up. That was on a Sunday, 10 years ago; but, seems like yesterday to me since I myself lost years of riding beginning around that time due to a knee issue... but, I'm back and now I frequently pass by a ghost bike that's on my favorite ride: a reminder that you many never see it coming.

pdlamb

While not wanting to quibble, I still disagree with the "significant body of evidence"; remember, the plural of anecdote is not data. Dr. Mandrola is a blogging EP cardiologist who experienced atrial fibrillation. Because of that blogging exposure, he's had people from all over the country reach out to him. Zinn is one example; how many Boulder, CO residents go to Louisville, KY looking for a cardiologist?


As a cyclist who enjoys riding long distances (200k-300k rides are great!), I'd love to see a statistically rigorous study that would shed some light on incidence of AFib on us so-called "endurance" athletes, and how that incidence compares with the general population. "I've had it and a lot of people like me have had it too" is not such a study.


FWIW, my cardiologist told me collateral vascularization from cycling saved my life when I had a non-STEMI. That's not data either, but it tells me I was on the right track.

Flounce

Do you really think this is based on a blogger's anecdote and there is no science behind it? Come on.

A 2 second quick google search will yield more stuff than you want to read, the paragraphs below are just cut and pasted from a random 5-year old review article that was one of the first to come up on a google search, just to give you a sense.

Calvo N, Brugada J, Sitges M, et al Atrial fibrillation and atrial flutter in athletes Br J Sports Med 2012;46:i37-i43.
Atrial fibrillation and atrial flutter in athletes | British Journal of Sports Medicine



"Several studies have described a relationship between long-term endurance sport practice and AF and AFl9–20 (table 1). In 1998, Karjalainen et al9 concluded that vigorous long-term exercise is associated with AF in healthy middle-aged men. They evaluated AF prevalence in veteran male orienteers and in a matched control group. LAF was diagnosed in 12 of 228 (5.3%) orienteers and in 2 of 212 (0.9%) controls (who also engaged in vigorous exercise) (p=0.012), the relative risk being 5.5 (95% CI 1.3 to 24.4) in orienteers. Our group analysed 1160 consecutive patients seen at the Outpatient Arrhythmia Clinic between October 1997 and March 1999. The proportion of sport activity among patients with LAF was significantly higher than among men from the general population in Catalonia (62.7% vs 15.4%).10 Regular sport activity was defined as high-intensity practice for at least 3 h a week for 2 years. An age-matched study including the same population of athletic men with LAF and age-matched controls selected from the general population of Girona, using data from the REGICOR (Registre Gironí del Cor) Study, confirmed that current and prolonged sport practice, defined as more than 1500 lifetime hours of intense endurance practice, was associated with a three times higher prevalence of LAF, and with five times higher prevalence of vagal LAF (OR 5.06, 95% CI 1.35 to 19).12 Baldesberger et al13 published similar data in a study of 62 professional cyclists who completed the Tour de Suisse professional cycling race at least once during the years 1955–1975. These cyclists were matched for age, weight, hypertension and cardiac medication with a control group of 62 male golfers who had never performed high-endurance training. The incidence of AF and AFl was significantly higher among athletes. Heidbuchel et al14 analysed the relationship between a history of endurance sports activity and/or its continuation and the risk of developing AF in patients with AFl undergoing right isthmus ablation. Of the 137 patients included, 31 (23% of the whole population) were mainly engaged in endurance activities. A history of endurance sports participation was an independent risk factor for AF development after flutter ablation (multivariate HR 1.81, 95% CI 1.10 to 2.98) and ongoing practice of an endurance sport after AFl ablation also increased the risk of AF (multivariate HR 1.68, 95% CI 0.92 to 3.06).

In a further cohort study, we evaluated the incidence of LAF in 183 individuals who ran the Barcelona Marathon in 1992 in comparison to 290 sedentary healthy individuals. The incidence of LAF was higher among marathon runners compared to sedentary men (annual incidence: 0.43/100 for runners, 0.11/100 for sedentary men) at 10 years of follow-up.15 In the GIRAFA (Grup Integrat de Recerca en Fibril-lacio Auricular) study,16 our group recruited patients with recent onset LAF attending the emergency room at our hospital between January 2001 and June 2005. They were matched by age and sex with healthy controls. An association of LAF and accumulated hours of physical activity was described: intense physical activity of >564 h was associated with a risk for developing AF of 7.31 (95% CI 2.33 to 22.96).

A recent meta-analysis by Abdulla and Nielsen17 demonstrated that the overall risk for AF was significantly higher in athletes than in controls (OR 5.29, 95% CI 3.57 to 7.85). Additionally, these results were confirmed by a large prospective cohort study of apparently healthy men.18 After adjustment for multiple potentially confounding lifestyle factors and health conditions, Aizer et al showed a 20% increased risk of developing AF among individuals with higher frequency of participation in a regular programme of vigorous exercise. More recently, Grimsmo et al19 analysed the prevalence of LAF in 117 cross-country skiers who competed in the Norwegian ‘Birkebeiner’ race of 58 km. They found that the prevalence of LAF was approximately 13% and bradycardia and long PQ time were independent predictors for the occurrence of LAF. Winhelm et al20 recruited non-elite athletes participating in The Grand Prix of Bern, one of the most popular 10-mile races in Switzerland, and found that the prevalence of AF was 6.7%.

In contrast to these previous studies, Pelliccia et al21 analysed the frequency of AF and supraventricular tachycardias in 1777 highly trained athletes. They reported a low incidence of AF among competitive athletes (0.2%), similar to that observed in general populations of comparable age and sex. However, in contrast to previous studies showing an association between AF and long-term endurance sport practice, the population analysed by Pelliccia et al comprised young athletes (mean age 24±6 years) involved in vigorous training programmes for a mean time period of only 6 years.

On the other hand, in the Cardiovascular Health Study,22 the incidence of AF in older adults (>65 years old) was lower with moderate-intensity exercise. However, this was not true with high-intensity exercise.

In summary, previous studies support an association between long-term endurance sports practice and the occurrence of arrhythmias such as AF or AFl in the middle-aged male population.
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Many of the described series report the presence of both AF and AFl in endurance athletes. Hoogsteen et al11 found that AFl was present in 10% of athletes with paroxysmal AF. Baldesberger et al13 evaluated arrhythmias in a long-term follow-up (30–50 years) after high endurance training in former professional cyclists, and found that AFl was more common than AF.

Heidbuchel et al14 described a higher incidence of AF after common flutter ablation in endurance athletes than in controls. According to these authors, flutter ablation could unmask the underlying atrial disease in endurance athletes, resulting in AF development during follow-up.

Based on these findings, endurance sport may contribute to the development of both arrhythmias.
---
The usual clinical profile of sport-related AF is a middle-aged male athlete, with a history of long-term regular endurance sport practice who is currently involved in regular, high-intensity endurance sport practice.

AF typically presents as a paroxysmal and highly symptomatic crisis, initially very occasional and self-limited, but becomes more frequent and prolonged over the years and can progress to persistent AF. Hoogsteen et al11 found that 17% exercise-related paroxysmal AF progressed to persistent AF and the GIRAFA study16 showed that 43% of patients with exercise-related AF were in persistent AF. Characteristically, AF episodes occur at night or after meals, revealing that AF may be related to increased vagal tone.16 The AF crisis frequently coexists with common AFl in many patients.
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Sport activity reduction

Furlanello et al48 described a good response to sport abstinence in top-level athletes with AF. Similarly, Hoogsteen et al11 showed that up to 30% of athletes experienced fewer episodes of AF by reducing sport activity. Therefore, the initial approach should be to recommend reducing physical activity. According to the Study Group on Sports Cardiology of the European Association for Cardiovascular Prevention and Rehabilitation,49 athletes in an early stage of paroxysmal AF should discontinue training for 2 months to stabilise sinus rhythm. The degree of improvement during this resting period will determine whether athletes are allowed to resume their training.

Task Force 7 of the 36th Bethesda Conference50 recommends that athletes with asymptomatic AF in the absence of structural heart disease can be permitted to participate in any competitive sport, provided they maintain a ventricular rate that increases and slows appropriately and is comparable to that of a normal sinus response in relation to the level of activity, while receiving no therapy or therapy with AV nodal-blocking drugs. Asymptomatic athletes who have AF episodes lasting 5–15 s with no increase in duration during exercise can participate in all sports. Athletes should take medications that slow down the ventricular rate and should stop exercise training if there is a history of high ventricular rate or haemodynamic instability during AF. In these patients, we usually prescribe AV-node slowing agents despite moderate bradycardia during sinus rhythm.
--
Conclusions
There is growing evidence that long-term endurance sports participation can result in cardiac structural changes and alterations in the autonomic system, which can result in the initiation and maintenance of AF and AFl, although the mechanisms explaining the relationship between these conditions remain to be elucidated.

Reducing sports activities may need to be considered as part of the therapeutic advice to minimise the risk of AF or AFl development in endurance athletes. In addition, CPVA and AFl ablation have been shown to be as safe and effective as in general population and should be recommended in highly symptomatic and drug-refractory endurance athletes."

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If you look into this a bit, it is clear that the science is behind this, it is not one random blogger's "N of 1" experience.

pdlamb

OK, there are some studies out there that indicate AFib may be correlated with exercise. That leaves open a few questions:


1. Is causation demonstrated? (A) No.


2. What is the mechanism for increased incidence? (A) Unknown.


3. What amount of exercise is ideal for reduces cardiovascular disease? (This one's a bit firmer at the low end...)


4. How much exercise is too much? I haven't seen any credible answers, has your google search found one?


5. Are there ways to mitigate the effects of "excess" exercise, should there be such a thing?


If you look into this a bit more, things get more and more murky.

Carbonfiberboy 

Yeah, correlation is not causation and the plural of anecdote is not evidence. BUT. At almost 73, I'm the oldest cyclist in my 130 person group who still rides hard and/or long distances. Everyone older than I has either left the group with Afib or curtailed their LD and intense riding because of Afib. Every one. This includes well-known randonneurs.

I'm still there because I never did the really hard stuff and not a whole lot of the almost really hard stuff, and also because I've only been riding hard for the past 22 years, while most have done endurance sports continuously since their teens.

There's been way too much poo-pooing by those who don't want to see the writing on the wall. This is dangerous for other riders who may well want to continue riding into their 90s. Please back it off.

BTW there's an 800-rider LD ride which I've ridden several times. Last year I was the first person in my age group to finish, so I'm not exactly a duffer, just not an elite. I've just been careful about intensity and recovery.

jeffpoulin

I think low intensity is the key to deriving maximum benefit out of any exercise (whether cycling, running, cross-country skiing, etc.). I find it better for cardiovascular fitness, less risk of afib, has fewer injuries to muscles and connective tissues, maximizes fat metabolism, and is less dangerous overall since you're generally going slower. For me, this means riding at about 15mph. I can pretty much do that for several hours/day and never feel tired or sick.

Back when I was running marathons, I would push myself to run as long and as fast as possible. I frequently got injured and/or sick just after a race. I thought it was bad luck then, but it's obvious to me now. High intensity over a long duration is just not healthy.

pdlamb

Am I missing something here? I seem to remember some of your postings in the last six months advocating hard hill climbs such as those you have been doing with a group for a number of years for training. Have you stopped doing those hard efforts so you can keep riding into your 90s? Do you have some evidence that what you're doing is below the hypothesized threshold that leads to AFib?

John_V 

Not to say that the articles are invalid but I just got done reading those articles that were posted by Flounce and according to the articles, I should be dead or on tons of medication. For the past 4 years, I've been riding between 9,000 and 12,000 miles/year doing 40-60 mile rides, 6 days a week. Some rides are low intensity while some are high intensity rides but on most rides, I mix the two. I've never had an episode of AFib or any other cardiac related problem. I'm 71 and the only medication I take is for my CML (a chronic form of leukemia). I've been told by my doctors not to stop what I'm doing so I guess I'm either one of the lucky ones that hasn't yet been affected by AFib or I'm just abnormal. Or maybe my rides aren't as intense as what the articles considers intense.

WNCGoater

Studies like these I typically put in the same file as the questions like, "You're not afraid of getting hit by a car while riding?" That would be Psalm 139:16

"...all the days ordained for me were written in your book
before one of them came to be."

Rowan

I am really sorry, but when I read the two words "review articles" these days, I don't proceed any further. It is lazy research, and just rehashes older proper (or even improper) research.

I've also done my own review research and found that of all people born in 1900, 100% of them died after eating carrots, even just once in their lives.

I'd suggest that in the post that Flounce cut-and-pasted, look at the percentages. Had there been figures of 70 or 80% of all endurance athletes being subjected to AF, I might have been concerned. As it is, cycling in its various forms including long-distance, got me to stop smoking, stop drinking alcohol in vast quantities, and keep my body weight under control. I have made it to 62, and there is a chance I might make it to 72. There is a good chance under the old regimen, I wouldn't have made it to 52!

Bandera

I don't think there are a great many people who upon hearing of this startling "Health Benefit" who are going to lay down the cash to invest in all of hardware/kit/gizmos/gimcracks required along with the big seat-time and plain hard work necessary to take up cycling long distances in variable weather conditions and challenging terrain if they just flat-out are not interesting in riding a bicycle.

"Nice" to hear of such, but it makes zero difference to my behavior as does the AFib stuff.
I ride the time/distances necessary for the Endurance I require, hit the hills because I like to and Power is always good and do short TT work and HIIT sprints to preserve what Speed I can. Rest and recovery are integral to the program as is the technique work that the FG provides on a seasonal/cyclical routine. How has this changed in >40 years? Not much.

-Bandera

unterhausen

The people I know that had AF problems were really hard-charging riders. I don't think that I ever was that, even when I was racing. Probably why I had no success. Such a small sample size, and it only happens to a relatively low percentage. I had a friend that took a chance he was one of 5% of people that something bad wasn't going to happen to. That was a bad choice, and he lost. Taking a chance that you are in the 95% is much less problematic. And it seems like for most people, the result of having this problem is that they have to stop riding so hard. Which is really not a problem, I would quit randonneuring. It's going to happen someday anyway.

ThermionicScott 

Some of us that are less religious have a similar mindset: "Que sera, sera."

Carbonfiberboy 

In the case of one person, that would be me, anecdote is andecdote. Doing what I do won't immunize you, duh. However I'm another one of those riders who never tried to be anything close to the best. I've been satisfied with being good enough to have fun with my friends. It's been very interesting to ride with the same group for over 20 years. Though of course it hasn't been the same people the whole time. Riders come and go, but the group ethos lives on.

I've seen a lot of people go through a lot of issues, both mental and physical. One of the interesting things to me is that in our group we don't see the same "F you people, I'm going to do whatever I want" attitude seen here on BF. Maybe that's why our group has continued for over 20 years.

And yes, I absolutely do hard hill climbs and advocate for doing them. But I've always limited my weekly zone 4 and zone 5 time. We know from studies and studies of studies that it takes the full range of aerobic and anaerobic efforts to stay in peak health. We also need the full range of nutrients and the full range of satiety and hunger to keep our systems in optimal tune.

I track everything and have records that go back many years. I always know my weekly totals for hours, mileage, time in zones, hours of sleep, average HR vs. effort, all that stuff. I track my morning resting and orthostatic heart rates. I never let things get too far away from normal rested state. For the past 15 years, I haven't done 2 hard workouts back-to-back or midweek high HR intervals. Those last 2 things probably differentiate me most from those who've gotten Afib or other health issues.

In my 50's, I used to average 18 or a little better on 60 mile, 50'/mile routes. Now I'm down to 16 or so on those same routes. On a 10,000' climbing route last year I was down to 15.7, down from 16+ a decade or so ago. I hope I'm not perceived as bragging with those numbers! Just saying that riding more moderately doesn't mean giving up.

Remember that it hasn't happened to you means that it hasn't happened to you yet. It's not that different from mountaineering. We all take risks. It's important to know what those risks are.

Rowan

Just to point out that the number of people that I know of who have died as a result of being hit by a motor vehicle in long-distance events in Australasia in the past decade far outweighs (by a factor of around six = 600%) the number of people who have died of heart-related illness on or out of events.

Let's put this in perspective, eh?

Let alone that the original intent of the thread was to highlight a NEW (not review) study that indicates something somewhat different from the current discussion.

As it is, I have held for a long, long time (since starting up cycling, in fact) that exercise has a positive effect on the immune system, and the increased blood flow from higher heart rate during exercise enables a faster exchange of nutrients to the cells, and in turn, faster removal and excretion of the toxins that are created in many illnesses.

Predisposition to certain ailments (maybe even A-defib in later life) may well have existed from birth, but because the generation that is now showing signs may not have survived as long as it has in previous generations (ie, we are living long enough), that predisposition has only become latent now.