Thrity-One-Year-Old Claims Cure for Type 1 Diabetes

A PICTURE OF BLOOD TESTING EQUIPMENT AND NEEDLES

A PICTURE OF BLOOD TESTING EQUIPMENT AND NEEDLESGoogle alerts frequently pairs ‘diabetes’ and ‘cure’ together, but most of the time the words don’t capture my attention. Even when ‘type 1 diabetes’ and ‘cure’ make the same sub-heading, I’m not jumping up and down.

Yeah, yeah, heard it, bought the tee shirt, and no impact on my life so far…

But The Sun newspaper carried a story this week about a 31-year-old who claims to have cured his type 1 diabetes with diet and exercise alone. Again, that approach can achieve results with type 2 diabetes but it’s the first time I’ve seen it accredited to a cure for type 1.

Exercise and diet

Daniel Darkes’ regime isn’t for the faint-hearted. He eats a diet high in zinc (nuts, oily fish and veg) and runs more than sixty miles a week.

But before you dig out your trainers and start stock-piling the Brazil nuts, Daniel’s type 1 diabetes has some qualifications. He has a rare, abnormal gene, which doctors believe might have restarted his pancreas.

The 31-year-old from Daventry in Northants developed diabetes eight years ago and stopped giving himself insulin last January (2017)*. He started cutting down on insulin after experiencing hypos in 2016. He travelled to the US in March 2017 to find out more. Doctors ran further tests to find out what we happening to his body.

Brain sending messages to pancreas

He was put on a fasting diet and exercised at the same time. The medical staff noted his brain had begun sending new signals to his pancreas, and he hasn’t injected himself with insulin ever since.

Daniel told The Sun that doctors believed his abnormal gene combined with exercise is the reason he’s been able to cure himself—it’s as if the gene acts as a back-up immune system and has recharged his pancreas.

He is still being monitored at Northamptonshire General Hospital.

Abnormal genes

I’m fascinated by this story—as I suspect most type 1s will be. I’m no medical expert so my opinions are qualified, but I suspect that Daniel’s abnormal gene plays a huge part in his ‘cure’ (and this won’t be regarded as such until he reaches the two-years-without-insulin mark). It’s also interesting that the description of his diet (scant as it is) sounds like a low-carb diet.

The article said that Daniel’s case “could provide a revolutionary new approach to treating type 1 diabetes”, while Diabetes UK said it couldn’t speculate on whether Daniel had ‘cured’ his diabetes or not, and that there was “no clear cure for type 1 or type 2 diabetes”.

 

*DISCLAIMER – please, for the love of all things injectable, do not skip your insulin injections if you have type 1 diabetes…

 

Coping with T1D in the Heat

Inforgrpahic about the heat by The Diabetes Diet

A screenshot of the weather in Scotland on The Diabetes DietHeavens above—this isn’t a post I’ve needed to write before but the last few weeks of incredible sunshine and heat in Scotland (Scotland! I’ll say it again, Scotland!) necessitates it.

If you’re a type 1, what special precautions do you need to take when the mercury rises? I prepared this handy infographic to help…

Please note—if you have neuropathy (nerve damage) this can affect your ability to sweat and therefore cool down. Go out early in the morning or later in the afternoon if you can, drink water to stay hydrated and exercise in air-conditioned gyms. Cut down on drinks with caffeine and alcohol, and take care of yourself as best you can.

Inforgrpahic about the heat by The Diabetes Diet

Public Health Collaboration Conference 2018: a great success for Lifestyle Medicine

I was delighted to attend and speak at the third PHC conference in London this year.  We met at the Royal College of General Practitioners in London on the sweltering weekend of the Royal Wedding. Apart from superb international speakers we were treated to low carb, high protein food, such as one would typically eat on a ketogenic diet. Instead of picking at our dinners as we often have to do with mass catering  we could eat the whole lot. Great!

Dr Peter Brukner from Australia started off the weekend with a review of what was happening in the low carb world. There are more and more reports coming out describing the advantages of ketogenic and low carb diets to different groups of people but the establishment are fighting back viciously as can be seen by the attack on Professor Tim Noakes in South Africa.  Indeed if his defence lawyers and expert witnesses had not worked for free he would be bankrupt.  This is a terrible way to wage war on doctors who are acting in the best interests of their patients.

Dr Aseem Malhotra also described bullying tactics that had been used against him when he was a junior doctor and first becoming publicly engaged in the low carb debate. I have been subjected to this as well.  Professor Iain Broom showed that the proof that low carb diets are superior to low fat diets goes back 40 years.

Dr Zoe Harcombe gave us an explanation of how the calories in- calories out idea just doesn’t add up. The well known formulas about how many calories you need to avoid to lose weight don’t work in practice because of the complex compensatory mechanisms we have to avoid death from starvation.  How you put this over to patients and give them useful strategies for weight loss and blood sugar control was explored by Dr Trudi Deakin.

Food addiction is a real issue, at least it is for the majority of the audience in attendance, who answered the sort of questions usually posed by psychiatrists when they are evaluating drug addiction.  Unlike drugs, food can’t entirely be avoided but ketogenic diets are one tool that can be used to break  unhealthy food dependence. This worked for presenter Dr Jen Unwin who at one point had a really big thing for Caramac bars.  I haven’t seen these in years but they did have a unique taste.

Dr David Unwin showed clearly that fatty liver is easily treatable with a low carb diet.

Dr Joanne McCormick describes how her fortnightly patient group meetings are making change accessible for her patients and how many GPs in the audience could broach the subject in a ten minute consultation.

The website Diabetes.co.uk will shortly be starting up a type one educational programme online that all are welcome to join. I discussed the issue of what blood sugar targets are suitable for different people and how they can achieve this with dietary and insulin adjustment.

Dr David Cavan spoke about reversing diabetes in patients in Bermuda. Although Bermuda looks idyllic the reality is that good quality food is about five times as expensive in the UK as it is all shipped in. Many inhabitants work their socks off but barely cover their costs and cheap sugared drinks and buns are their staple diet. Despite these setbacks he managed to persuade a lot of diabetic patients to ditch the carbs and this had favourable results even after the educational programme had stopped.

A cardiologist Dr Scott Murray described the effects of metabolic syndrome on the heart and really why sticking stents in diseased arteries is too little, too late. He is convinced dietary change is needed to reverse and prevent heart disease. This is the first time I have been told that certain types of heart failure and atrial fibrillation are direct effects of metabolic syndrome on the heart.

The importance of exercise for physical and mental well being was not neglected and we had Dr Zoe Williams describing the great benefits that even the minimum recommended exercise can produce.

Dr Simon Tobin and Tom Williams spoke enthusiastically about Parkrun. This is a free event that runs every Saturday morning in parks all over the world. You can choose to walk, jog or run the course.

Claire McDonnell-Liu is the mother of two children who have greatly benefited from a ketogenic diet. The conditions are urticaria and epilepsy.  Although NHS dieticians do help families with childhood epilepsy who want to use a ketogenic diet, they can’t do it unless drugs have failed, as this is NICE guidance. I wonder how many children would benefit in fit reduction without side effects of drugs if this guidance was changed?

This was a fabulous conference with a positive enthusiastic vibrancy. Thanks to Sam Feltham for organising this event especially since he has become a new dad as well.

The Public Health Collaboration are putting all the talks on You Tube.

I was interviewed about diabetes and women’s health issues for Diabetes.co.uk and Diet Doctor and these interviews and many others will be available for you all to see to improve your lives with diabetes.

 

 

 

BMJ: Regular, physical exercise is the miracle cure to ageing

Tai chi.jpg

Adapted from Scarlett McNally’s article in the BMJ 21 Oct 17

The NHS and social care are inextricably intertwined. The rising number of older people is frequently blamed. The rising social care costs in this age group can be modified however. NICE in 2015 said, “disability, dementia and frailty can be prevented or delayed”.
The need for relatives or paid carers arises when someone can no longer perform the activities of daily living such as washing, dressing and feeding themselves. For some people the ability to get to the toilet in time is the critical thing between having carers come to their own home twice a day and being admitted to a full time care facility.
The cost of care rises five times for those admitted to residential facilities. An average residential placement costs £32,600 a year and may be needed for months, years or decades.
A cultural change is needed so that people of all ages aspire to physical fitness as a way of maintaining independence into old age. There just doesn’t seem to be the local or national infrastructure to support this however.
Ageing is a normal, if unwelcome, biological process that leads to a decline in vision, hearing, skin elasticity, immune function and resilience, which is the ability to bounce back.
The decline in fitness with age starts around the age of 30 and accelerates after the age of 45. Things move downhill even faster if someone has a sedentary job that involves car driving and computer work. Diabetes, dementia, heart disease and some cancers become more common.
Some may think that fitness in old age is down to genes and luck but social strata differences exist with good nutrition and exercise as major factors in enhancing health and fitness into old age.
Apart from getting older, environment and lifestyle affect disease onset. At the age of 40, some forty percent of people have at least one long term condition and the rate goes up by ten percent each decade. As environmental and behavioural factors stack up over time, more people develop an increasing number of diagnoses. Yet, small habits such as cycling to work, can mitigate the effects of a sedentary job.
As time goes on, a person’s independence can be compromised by well -meaning carers and relatives doing more for their charges rather than letting them do things for themselves.
Genetics are thought to play only 20% of the part in the development of modern diseases. Lack of fitness has more of a part to play than disease and multiple morbidity.
Pain can lead people to limit their activity because they think it could make their illness worse, but strength, stamina, suppleness and balance training are usually needed more rather than less as you get older and accumulate illnesses.
These factors improve cognitive ability in midlife through to a person’s 80s. They can reduce the onset of dementia. Increasing independence results.
The Academy of Medical Royal Colleges go as far as describing exercise as “the miracle cure”. Improving the time to stand from sitting down, walking, and resistance training exercise all produce a dose response effect with the most frail benefitting the most. Any exercise or activity such as gardening that gets you slightly breathless and is done in ten minute bursts or longer counts as the 150 minutes minimum as recommended in the UK.
Stopping smoking and limiting alcohol are also worthwhile interventions. Gyms, walking groups, gardening, cooking clubs and volunteering have all been shown to improve the health and well- being of people of all ages with long term conditions.
When people are admitted to hospital they often experience a rapid decline in function. Patients are not allowed to move about or go to the toilet themselves in case they fall. The numbers of these are considered adverse incidents and are strongly discouraged. Thus the ambulant end up chair or bedbound. Most inpatients spend 80% of the time in bed and more than 60% come out with reduced mobility.
All patients should be encouraged to start an activity programme and gradually increase the frequency, intensity, and time that they do it.
The outdoor environment can be improved by even pavements, open spaces, tables and seating in public areas, safe cycle lanes and restriction in car use.
Money may need to be shifted from passive care and polypharmacy to activity and rehabilitation services.
People need to concentrate on being active every day. A quarter of women and a fifth of men do no activity whatsoever in a week never mind the minimum recommended 150 minutes a week.
In the UK the total social care bill is over £ 100 billion which is virtually the same as spent in the NHS.
The cost of care doubles between the ages of 65 and 75 and triples between 65 and 85. If everyone was just a bit fitter, the savings would add up.
Individuals need to see it as their responsibility to stay fit or improve their fitness. There needs to be more national coordination regarding the environment, transport and our working schedules so that we can all stay that bit functionally younger into old age. We could be making the difference between staying at home or depending on social and residential care.

Kris Kresser: Why has the American approach to heart disease failed?

Why Has the American Approach to Heart Disease Failed?
on April 18, 2017 by Chris Kresser 

Tsimane 2

A recent New York Times article correctly suggests that diet and lifestyle changes are far more effective ways to prevent and treat heart disease than statins and stents. But what diet, and what lifestyle? Is it as simple as avoiding “artery-clogging saturated fat,” as the author suggests? Read on to find out why the American approach to heart disease has really failed.
Jane Brody wrote an article in The New York Times called “Learning from Our Parents’ Heart Health Mistakes.” She argues that despite decades of advice to change our diet and lifestyle in order to reduce our risk of heart disease, we still depend far too much on drugs and expensive procedures like stents.
She says:
Too often, the American approach to heart disease amounts to shutting the barn door after the horse has escaped.
To support this argument, she refers to a recent paper published on the Tsimane, an indigenous population in the Bolivian Amazon. The study found that the rate of coronary atherosclerosis in the Tsimane was one-fifth of that observed in the United States (and the lowest that has ever been measured). Nearly nine in 10 Tsimane had unobstructed coronary arteries and no evidence of heart disease, and the researchers estimated that the average 80-year-old Tsimane has the same vascular age as an American in his mid-50s.
I certainly agree with Ms. Brody so far, and her analogy that the American approach to heart disease amounts to shutting the barn door after the horse has escaped is spot on.
The problem is what comes next, as she attempts to answer the question of why the Tsimane have so much less heart disease than Americans:
Protein accounts for 14 percent of their calories and comes primarily from animal meats that, unlike American meats, are very low in artery-clogging saturated fat. [emphasis mine]
Does saturated fat “clog” your arteries?
Artery-clogging saturated fat? Are we still using that phrase in 2017?
As I’ve written before, on average, long-term studies do not show an association between saturated fat intake and blood cholesterol levels. (1) (I say “on average” because individual response to saturated fat can vary based on genetics and other factors—but this is a subject for another article.)
If you’re wondering whether saturated fat may contribute to heart disease in some way that isn’t related to cholesterol, a large meta-analysis of prospective studies involving close to 350,000 participants found no association between saturated fat and heart disease. (2)

Does saturated fat really “clog” your arteries?

Are “clogged arteries” the cause of heart disease?
Moreover, as Peter Attia eloquently and thoroughly described in this article, the notion that atherosclerosis is caused by “clogged arteries” was shown to be false many years ago:
Most people, doctors included, think atherosclerosis is a luminal-narrowing condition—a so-called “pipe narrowing” condition.  But by the time that happens, eleven other pathologic things have already happened and you’ve missed the opportunity for the most impactful intervention to prevent the cascade of events from occurring at all.
To reiterate: atherosclerosis development begins with plaque accumulation in the vessel wall, which is accompanied by expansion of the outer vessel wall without a change in the size of the lumen. Only in advanced disease, and after significant plaque accumulation, does the lumen narrow.
Michael Rothenberg also published an article on the fallacy of the “clogged pipe” hypothesis of heart disease. He said:
Although the image of coronary arteries as kitchen pipes clogged with fat is simple, familiar, and evocative, it is also wrong.
If heart disease isn’t caused by “clogged arteries,” what does cause it?
The answer to that question is a little more complex. For a condensed version, read my article “The Diet-Heart Myth: Why Everyone Should Know Their LDL Particle Number.”

For a deeper dive, read Dr. Attia’s article.
Here’s the 15-second version, courtesy of Dr. Attia:
Atherosclerosis is caused by an inflammatory response to sterols in artery walls. Sterol delivery is lipoprotein-mediated, and therefore much better predicted by the number of lipoprotein particles (LDL-P) than by the cholesterol they carry (LDL-C).
You might think that I’m splitting hairs here over terminology, but that’s not the case. It turns out that this distinction—viewing heart disease as caused by high LDL-P and inflammation, rather than arteries clogged by saturated fat—has crucial implications when it comes to the discussion of how to prevent it.
Because while it’s true that a high intake of saturated fat can elevate LDL particle number in some people, this appears to be a minority of the population. The most common cause of high LDL-P in Americans—and elsewhere in the industrial world—is almost certainly insulin resistance and metabolic syndrome. (I explain why in this article.)
And what is one of the most effective ways of treating insulin resistance and metabolic syndrome? That’s right: a low-carbohydrate, high-fat diet!
News flash: diets high in saturated fat may actually prevent heart disease.
Perhaps this explains why low-carbohydrate, high-fat diets (yes, including saturated fat) have been shown to reduce the risk of heart disease.
For example, a meta-analysis of 17 low-carb diet trials covering 1,140 obese patients published in the journal Obesity Reviews found that low-carb diets were associated with significant decreases in body weight, as well as improvements in several CV risk factors, including decreases in triglycerides, fasting glucose, blood pressure, body mass index, abdominal circumference, plasma insulin, and C-reactive protein, as well as an increase in HDL cholesterol. (3)
(In case you’re wondering, low-carb diets in these studies had a null effect on LDL cholesterol: they neither increased nor decreased it.)
Saturated fat is a red herring.
Instead of focusing so much on saturated fat intake, which is almost certainly a red herring, why not focus on other aspects of the Tsimane’s diet and lifestyle that might contribute to their low risk of heart disease?

For example:
They are extremely active physically; Tsimane men walk an average of 17,000 steps a day, and Tsimane women walk an average of 15,000 steps a day—and they don’t sit for long periods. Ms. Brody does mention this in her article.
They don’t eat processed and refined foods. We have been far too focused on calories and macronutrient ratios and not enough on food quality. We now know that hunter–gatherers and pastoralists around the world have thrived on both high-carbohydrate, low-fat diets (like the Tsimane, who get 72 percent of calories from carbohydrate) and low-carbohydrate, high-fat diets (like the Masai and Inuit).

But what all hunter–gatherer diets share in common is their complete absence of processed and refined foods.
Perhaps if we stopped focusing so much on the amount of fat and carbohydrate in our diet and started focusing more on the quality of the food we eat, we’d be better off.
And of course we also need to attend to the many other differences between our modern lifestyle (which causes heart disease) and the ancestral lifestyle (which prevents it), including physical activity, sleep, stress, light exposure, play/fun, and social support.
The Tsimane study illustrates exactly why an evolutionary perspective on diet, lifestyle, and behavior is so important. It helps us to generate hypotheses on what aspects of our modern way of life may be contributing to chronic diseases like atherosclerosis and gives us ideas about what interventions we need to make to prevent and reverse these diseases.

Thinking clearly: What is mindfulness all about?

Do you ever just wish you could get someone who knows virtually everything that’s known about the brain and quiz them about mindfulness? Well, I do – a lot – and I just got my wish!

It is my pleasure to present this interview with John McBurney MD. A practicing physician with of over 35 years’ experience, he is board certified in Neurology, Clinical Neurophysiology and Sleep Medicine. Dr. McBurney maintains a daily mindfulness meditation practice as well as home yoga practice.

Could you describe the neurological response to mindfulness practice?

Mindfulness practice ultimately comes down to the concept of neuroplasticity.

In mindfulness, in cultivating awareness of the breath and voluntary moment by moment awareness of the brain, we are training the brain – just like when you are learning to play the violin or any other complex skill – we are training to break out of those self-referential ruminative recursive mental states and to achieve an orientation toward the outer world and in the present moment rather than anticipating the future or reliving the past.

contemplative neuroscience mechanisms behind mindfulness

 Could we be losing something by focusing more on the external realities rather than the self?

Occasionally, we do hear of adverse experiences arising from mindfulness. With any robust intervention there are always potential risks.

How long does it take for mindfulness to have a noticeable effect?

The results can happen almost immediately, however, they are also cumulative. We are still figuring out what the minimum effective dose is. 

What is the relevance of the changes in functional connectivity in the brain in someone who has devoted  a monumental amount of time to meditation, such as Tibetan monks, who may put in more than 10,000 hours in to their practice, compared to the likes of you and me?

A very neat study was published by David Cresswell in Biological Psychiatry in 2016. They invited individuals with high level of stress, unemployed adults, to a weekend retreat experience. They were randomised to in 2 groups:

  • a 3 day mindfulness retreat (the treatment group) and
  • a 3 day relaxation retreat where they read stories, told jokes and had a good time (the control group).

The study was conducted in one centre over one weekend, so it is well controlled. Initially, both groups rated the interventions as being equally helpful to them, subjectively.

The researchers looked at the functional connectivity between the dorsolateral prefrontal cortex and the cingulate gyrus. They also looked at Interleukin-6, a known marker of inflammation, that has been previously shown to be elevated in stressed out unemployed people.

Even with this brief weekend mindfulness intervention, the treatment group developed increased connectivity between the dorsolateral prefrontal cortex and the cyngulate gyrus. There was a neuroplastic response even after a 3 day mindfulness retreat. This was also associated with a decrease in the marker IL-6. Even after 4 months, IL-6 was decreased in the treatment group, but in the control group, IL-6 levels continued to rise, independent of whether they managed to get a job or not.

This is also relevant to doctors, who are at high risk for burnout. Because of their work commitments, the mindfulness retreat for doctors was condensed from the standard 8 week model developed by John Kabat-Zinn to a weekend intervention. The question was: does the weekend model work? The research at the University of Wisconsin where this was developed was reassuring: the residents are less stressed out, more effective and have a greater level of satisfaction.

We still don’t know the absolute minimum dose, but it seems that a weekend of mindfulness can be life-changing for the brain.

Another paper published in PLOS ONE from the Benson-Henry Institute for Mind Body Medicine in Harvard looked at the practices such as meditation, prayer, mindful yoga, Tai-Chi, Qi Gong, etc, i.e. ones that elicit a relaxation response (as opposed the stress response).

This study showed that in both novice and experienced practitioners of relaxation response modalities, there were changes in the epigenetic transcription of the genome. There was upregulation of pathways associated with mitochondrial integrity, downregulation of inflammatory pathways, improved insulin-related metabolism and improved nitric oxide signalling.

Long term potentiation, the standard mechanism for memory formation, strengthens existing neural connections. This happens immediately, as you read this. Over time, long term potentiation leads to formation of new connections,through synaptogenesis, dendritic arborisation and neurogenesis i.e. brain structure changes. In turn, this affects the most neuroplastic neurons located in the hippocampus.

mindfulness minimum effective dose response neurology

In reference to this fascinating recent study of the fight or flight response, it seems plausible that breathing regulates our stress levels much more than conscious thought. Could you explain the significance of this in terms of mindfulness?

The ancients believed that emotions reside in the body. This comes up a lot in serious yoga classes.

This highly innovative study shows that the control of the adrenal medulla – the main effector of the stress response – is not from the conscious ruminating thinking centres, but by the motor and sensory cortex.

This explains why breathing, as well as yoga and Tai-Chi, are an important part of meditative practice. In my experience, these kind of interventions do affect the stress response in a beneficial way.

Mindful exercise exists in many form. For example, weightlifters need to be very mindful to maintain perfect form. Cycling is another example: it is vital to concentrate on every pedal stroke and maintain an even cadence. Once you start to day dream, you notice straight away that your output is way worse. This overlaps with the concept of flow. It is about getting in the zone. There is a very inspiring TED talk by Judson Brewer MD, Ph.D. that explains the physiology behind flow and how it is augmented by mindfulness. Mindfulness is work, and it does require discipline. There is a paradox here of non-striving and non-doing while also being disciplined.

You are a sleep medicine expert. Could you comment on the relationship between mindfulness and sleep?

Insomnia is a complex problem with many causes. However, for most people with idiopathic insomnia, the cause is these self-referential recursive ruminations. They aren’t able to “turn their brain off”. Through mindfulness practice, they are generally able to tame the default mode network that’s responsible for ruminating and daydreaming. A simple strategy would be to lie in bed and concentrate on the breath. This would ease the transition between wakefulness and sleep.

mindfulness default mode network neurological basis for the self

Mindfulness is a mainstay treatment for many mental health disorders. What about use of mindfulness in the treatment for organic pathology of the brain usually treated by neurologists?

There is some preliminary data that mindfulness training has a beneficial effect of seizure frequency in patients with epilepsy. It is a medical condition associated with tremendous anxiety and stress, so mindfulness could have a significant benefit in more than one way. It may even have a benefit it terms of remembering to take medication on time, etc.

Some robust studies show that the frequency of relapse in multiple sclerosis decreases with mindfulness intervention. The effect from mindfulness is similar in magnitude to the effect from beta-interferon. 

John Kabat-Zinn used to take the patients who suffered from chronic pain or had diseases for which we had no answer, and those patients got better. Even beyond neurology, there is some evidence that mindfulness can have benefits in psoriasis. We are probably only at the bottom of this mountain.

Dr McBurney has given me so much to think about. I will follow up with part 2 of our discussion that focuses more on the philosophical and life experience aspects of mindfulness once I wrap my head around it.

neurological path mindfulness default mode network adrenal medulla

Gretchen Reynolds: You are never too old to give up on exercise

cyclist robert marchand

At the age of 105, the French amateur cyclist and world-record holder Robert Marchand is more aerobically fit than most 50-year-olds — and appears to be getting even fitter as he ages, according to a revelatory new study of his physiology.

The study, which appeared in December in The Journal of Applied Physiology, may help to rewrite scientific expectations of how our bodies age and what is possible for any of us athletically, no matter how old we are.

Many people first heard of Mr. Marchand last month, when he set a world record in one-hour cycling, an event in which someone rides as many miles as possible on an indoor track in 60 minutes.

Mr. Marchand pedaled more than 14 miles, setting a global benchmark for cyclists age 105 and older. That classification had to be created specifically to accommodate him. No one his age previously had attempted the record.

She was particularly interested in Mr. Marchand’s workout program and whether altering it might augment his endurance and increase his speed.

Conventional wisdom in exercise science suggests that it is very difficult to significantly add to aerobic fitness after middle age. In general, VO2 max, a measure of how well our bodies can use oxygen and the most widely accepted scientific indicator of fitness, begins to decline after about age 50, even if we frequently exercise.

But Dr. Billat had found that if older athletes exercised intensely, they could increase their VO2 max. She had never tested this method on a centenarian, however.

But Mr. Marchand was amenable. A diminutive 5 feet in height and weighing about 115 pounds, he said he had not exercised regularly during most of his working life as a truck driver, gardener, firefighter and lumberjack. But since his retirement, he had begun cycling most days of the week, either on an indoor trainer or the roads near his home in suburban Paris.

Almost all of this mileage was completed at a relatively leisurely pace.

Dr. Billat upended that routine. But first, she and her colleagues brought Mr. Marchand into the university’s human performance lab.

They tested his VO2 max, heart rate and other aspects of cardiorespiratory fitness. All were healthy and well above average for someone of his age. He also required no medications.

He then went out and set the one-hour world record for people 100 years and older, covering about 14 miles.

Afterward, Dr. Billat had him begin a new training regimen. Under this program, about 80 percent of his weekly workouts were performed at an easy intensity, the equivalent of a 12 or less on a scale of 1 to 20, with 20 being almost unbearably strenuous according to Mr. Marchand’s judgment. He did not use a heart rate monitor.

The other 20 percent of his workouts were performed at a difficult intensity of 15 or above on the same scale. For these, he was instructed to increase his pedaling frequency to between 70 and 90 revolutions per minute, compared to about 60 r.p.m. during the easy rides. (A cycling computer supplied this information.) The rides rarely lasted more than an hour.

Mr. Marchand followed this program for two years. Then he attempted to best his own one-hour track world record.

First, however, Dr. Billat and her colleagues remeasured all of the physiological markers they had tested two years before.

Mr. Marchand’s VO2 max was now about 13 percent higher than it had been before, she found, and comparable to the aerobic capacity of a healthy, average 50-year-old. He also had added to his pedaling power, increasing that measure by nearly 40 percent.

Unsurprisingly, his cycling performance subsequently also improved considerably. During his ensuing world record attempt, he pedaled for almost 17 miles, about three miles farther than he had covered during his first, record-setting ride.

He was 103 years old.

These data strongly suggest that “we can improve VO2 max and performance at every age,” Dr. Billat says.

There are caveats, though. Mr. Marchand may be sui generis, with some lucky constellation of genes that have allowed him to live past 100 without debilities and to respond to training as robustly he does.

Lifestyle may also matter. Mr. Marchand is “very optimistic and sociable,” Dr. Billat says, “with many friends,” and numerous studies suggest that strong social ties are linked to a longer life. His diet is also simple, focusing on yogurt, soup, cheese, chicken and a glass of red wine at dinner.

But for those of us who hope to age well, his example is inspiring and, Dr. Billat says, still incomplete. Disappointed with last month’s record-setting ride, he believes that he can improve his mileage, she says, and may try again, perhaps when he is 106.