Mixed Messages …

The morning rides have been a bit on the chilly side. I had a close brush with frostbite just the other day, well cold fingers anyway. Flame Robins have deserted the high country for the winter and have been moving through this district in recent days, always a welcome sight. Winter is also the time when we see more Crimson Rosellas and Grey Currawongs.

But here we are only just past the winter solstice and some of the birds are singing from a different hymn book entirely. Just west of Dunolly in recent days I have encountered a Fan-tailed Cuckoo emitting its mournful whistle and yesterday I was swooped by a couple of Magpies, one in desultory fashion and one with great enthusiasm. The latter made contact with my bike helmet a couple of times. I knew there was a good reason to wear one.

We are, of course, talking about the Australian Magpie Gymnorhina tibicen not the original Eurasian Pica pica.

Frostbite … ?

It was a chilly one this morning. The grass was crackling under my feet and the puddles were frozen as I got the bikes out of the garage.

Readers from elsewhere in the world may have the notion that Australia is a land of never ending sunshine and warmth. Not so. South-east Australia even has some ski resorts. The Victorian goldfields are on the inland side of the Great Dividing Range away from the moderating influence of the sea. We have some knockout frosts. The last couple of mornings -2° C.

Having said that, though, it’s the cloudless nights that produce the lowest temperatures. Cloud cover helps to hold the warmth in. Snow (below 1000) meters is therefore unusual.

Plugging away at 25 kph into a 5 km headwind made the fingers numb after a while. I haven’t solved the problem of the appropriate gloves yet – I’m on to my third pair presently. Do avoid neoprene it doesn’t keep out the cold but sure does a good job of keeping in the sweat. Anyway, the mind turned to consideration of frostbite. Is the wind that is generated by the forward motion of the bike sufficient to turn an uncomfortable experience into a dangerous one?

Once home again and thawed out I consulted the internet. I found a couple of windchill calculators that talk metric after a fashion. One at calculator.net can be persuaded to accept metric input. It then calculates a metric answer and also a Fahrenheit answer which you can look up in a nice graphic.

Another at  romseyaustralia.com is very informative but having got your answer you consult a table to discover the likely outcome for your fingers and toes which is not quite as intuitive as the graphic. It was at this site that I learnt …

Twelve volunteers (six men and six women) participated in the clinical trials. These consisted in four walks, at 4.8 km/h, on a treadmill in a refrigerated wind tunnel at the Defence and Civil Institute of Environmental Medicine in Toronto, Canada: one walk at each of -10, 0 and +10 deg C, plus a “wet trial” at +10 deg C during which participants received, every 15 seconds, a light one-second splash of water in their faces. During each 90-minute walk, the volunteers were walking while facing a wind of 2 metres per second (m/s) for 30 minutes, followed by 30 minutes at 5 m/s, and 30 minutes at 8 m/s (or about 4, 10 and 16 mph, respectively). Sensors were fixed to participants’ forehead, cheeks, chin and nose, as well as to the inside of one cheek, to measure skin temperature and heat loss. The results from these trials were used to determine the various thresholds for frostbite, as seen on the new wind chill chart.

The new wind chill equation is now in use in both Canada and the United States. Therefore, there is now a consistent wind chill formula across North America.

Where would we be without volunteers?

Should you distrust the calculator and prefer to compute your own here’s the formula …

Twind_chill = 13.12 + 0.6215*T – 11.37*(v0.16) + 0.3965*T*(v0.16)

If you were surprised to discover that Australia has ski resorts you probably won’t be surprised to discover that my fingers and toes were in no danger whatever. At -2° C. the wind would be uprooting trees before it caused sufficient chilling to freeze my extremities. Hypothermia, though, is another issue.

Colbinabbin …

More silo art, the paint has barely dried.

Colbinabbin is about 160 km north of Melbourne and about 54 km from the nearest large town, Bendigo.

The artwork is by the Benalla artist Tim Bowtell and it is a splendid accomplishment. It celebrates local history from the Colbo Picnic of the early 1900s through the days when steam was king to a tractor pull from the 1980s.

For the photographer interested in where the light will be coming from the artwork faces south.

Colbinabbin is situated in north central Victoria. It’s the home of the Colbinabbin Football and Netball Club, AKA the Hoppers and it has a shop or two. Parking and visibility of the art is excellent. It’s a terrific project that I’m sure will do the town some good.

Keep Living Fast …

If you are overweight or obese your chances of dying of any cause are raised.

From – Body-mass index and all-cause mortality: individual-participant-data meta-analysis of 239 prospective studies in four continents. Lancet. Aug 2016.

If you were one of the nearly four million people in this study the best weight to be was the one that put your Body/Mass Index under the red arrow. As it goes up or down so too do your chances of dying. It’s a J curve.

If you are young and obese you have the most to gain from losing weight. It is not easy but some succeed. You can give it a go or you can shriek about fat shaming and stuff another ice cream in your face.

If you’re obese and really lucky you may be metabolically healthy. It’s true for a minority. On the other hand some people of normal weight fall prey to those ills we associate with obesity, the dreaded metabolic syndrome. It does rather complicate the decision regarding the ice cream.

But wait it gets worse.

If you are a baby boomer or, my goodness, even older there are a number of confounding issues. Declining muscle mass being replaced with fat can bring all the disadvantages of obesity at a normal or not greatly elevated BMI. Add to that the fat distribution – middle aged spread tends to go around the middle where it does more harm than subcutaneous fat. You may be in more trouble than you think … or less.

I’m still exactly the same height I was lying about when I was 18 but some people have shrunk. This would increase their apparent BMI even if they haven’t put on a gram in the meanwhile. (Do I get extra consideration for bow legs?).

Next thing to consider is the obesity paradox. If BMI is plotted against all cause mortality in the elderly a different picture emerges than the one above. A higher BMI can appear to be protective. The simplest explanation for this is that death is fairly common in this age group and is often preceded by a period of wasting. Alternatively it may be because those most susceptible to the ills of obesity have already been eliminated from the cohort.

So if unintentional weight loss clouds the picture is intentional weight loss safe or not?

Intentional weight loss, even when excess fat mass is targeted also includes accelerated muscle loss which has been shown in older persons to correlate negatively with functional capacity for independent living. Sarcopenic obesity, the coexistence of diminished lean mass and increased fat mass, characterizes a population particularly at risk for functional impairment …. Miller & Wolfe.

Failed weight loss in a sedentary population invites the worst of both worlds – lose fat and muscle regain only fat. Weight loss in the elderly regardless of intentionality also  carries an increased risk of subsequent hip fracture.

No surprise then that health care professionals are divided on whether weight loss should be recommended to their elderly patients.

This little essay draws heavily on a review paper by Gill, Bartels & Batsis.  Their conclusion is fairly positive …

The number of older adults is projected to increase substantially in the coming decades and addressing obesity is essential for the health of this rapidly growing population. Though the “obesity paradox” has contributed to a lack of attention to addressing obesity as a major health problem in older adults, weight loss and improved fitness in obese older adults has been shown to improve function and multiple health indicators. Though physical activity and diet alone can improve outcomes, randomized controlled trials showed better outcomes when they were combined. The process of activity prescription should be patient-centered in order to develop a plan that is relevant to the older adult’s goals and achieve the overarching purpose of improved quality of life.

If you’re no spring chicken and thinking of shedding some weight it’s worth a read. A chat with your doctor would also be a good idea. Diet and exercise beats either alone.

My choice was to start cycling coupled with resistance training and a low-carb diet taking care to keep the protein intake up. All appears to be going well, the hips are still intact (you’d need oxy-acetylene equipment to get through one of them).

Previous failure has taught me that it ain’t over until the fat lady is singing about how much weight she’s lost but cycling is low impact compared to running and the keto diet involves little will power compared to calorie restriction diets. Confidence remains high.

Live Fast …

… Die young. I have no particular objection to the first half of that particular motto but even as a youngster didn’t feel a great affinity with the second half. Nor has it been popular generally – not dying young is the reason we have a population that is on average getting older.

But, as I’ve said before, if I can have some extra please insert it in the middle not add it on the end. Anywhere in the healthspan will do fine just not on the lingering tail of the lifespan.

Increased life expectancy has largely been the result of public health measures, road safety legislation, improved medical services and an avoidance of widespread warfare. It’s all about keeping us from dying. Enjoying good health is quite distinct from merely surviving. This is where the user pays principle in healthcare cannot be avoided. It’s your body.  You will pay for what you do with it.

As a community we have shown a willingness to look after ourselves. Our intentions are good. We have, in the main, listened to good advice and reduced our smoking. We have also listened to dietary advice. Consumption of those things that we have been urged to reduce has gone down but nonetheless our weight has gone up. I think US data is good for Australia as well.

And the timing of the obesity pandemic is a bit suspicious …

If I were defending the guidelines I’d be quick to point out that correlation is not proof of causation but hey, saturated fat was convicted on flimsier evidence than this.

So was it bad advice or simply an unequal battle against sugar – cheap, addictive and toxic? Nowhere in the guidelines did it say eat more calories but that is indeed what we’re doing.

Or is it, instead, a function of our ageing, a collective middle aged spread? If we turn our heads one morning, catch sight of our belly in profile and achieve enlightenment what should we do about it?

Too Much Exercise …

I was extolling the virtues of cycling to a cardiologist. I suspect that he wasn’t one to exercise a lot himself. His first response was to say “That’s all very well unless you rip off a plaque and pop yourself off with an infarct”. There followed a couple of digs about shaving my arms and legs before the coup de grace “It’s a J curve you know”.

J-curves are not uncommon in medicine. Vitamin A for instance is essential, too little is bad for you, the right amount is exactly that while too much is harmful even lethal. Similar curves obtain for other variables such as weight.

From – Body-mass index and all-cause mortality: individual-participant-data meta-analysis of 239 prospective studies in four continents. Lancet. Aug 2016.

Body weight and all cause mortality are high to the right. The risk of death comes down with body weight but rises again to the left as weight reduces below the optimum.

My cardiologist friend was suggesting that  a little exercise would be good but too much would put me in an early grave. It is not hard to find evidence to support his point of view.

Lee et al evaluated the records of 23,257,723 Koreans age 20 yr or more who had undergone one biennial medical evaluation by the National Health Insurance Corporation. Their level of physical activity was assessed by questionnaire.

A reverse J-shaped risk curve was observed, with the lowest mortality risk in the participants exercising 4 to 5 days per week

A significantly increased risk of death was found in those that did not exercise and those who exercised 6 or 7 days a week.

There are problems with epidemiological studies based on questionnaires. If you ask people how much they exercise, eat, earn or if they’re unfaithful to their spouse you may not get a truthful answer. In a Norwegian study (Dyrstad et al) 1751 adults (19–84 yr) wore an accelerometer for 7 days and filled out a questionnaire regarding their physical activity. The discrepancy between the self reported and measured activity was revealing. For example men reported 47% more moderate to vigorous physical activity compared with women but there was no difference between sexes in the accelerometer data.

Their conclusion …

The present study shows large variations between self- reported and accelerometer-measured physical activity and sedentary time.

The general agreement between self-reported and accelerometer-measured  physical activity was poor

The questionnaire and the accelerometer came in the same envelope. The inaccuracy is unlikely to be due to intentional lying.

So garbage in garbage out.

A review article by Harvey B Simon, in the American Journal of Medicine 2015 entitled Exercise and Health: Dose and Response, Considering Both Ends of the Curve makes good sense of a confusing issue. It is well worth a read in its entirety. To save you the effort I will grab the key quotes but bear in mind that I am not without bias.

The benefits associated with regular exercise include substantial protection against heart attack, stroke, hypertension, peripheral artery disease, diabetes, obesity, erectile dysfunction, sarcopenia, osteoporosis, depression, dementia, and common malignancies such as breast and colon cancers. Regular exercise enhances the quality of life, slows the physiological consequences of aging, and promotes longevity.

Although these benefits have been widely publicized, only a minority of Americans exercise regularly.

It’s good for us but by and large we don’t do it. Could it be because it’s potentially fatal?

Despite the man-bites-dog publicity that announces the death of an athlete during competition, these tragic events are actually quite uncommon. Males are at higher risk than females in all age groups. Among young athletes, about two-thirds of these deaths are due to trauma and other nonmedical causes such as drug abuse and heatstroke; hypertrophic cardiomyopathy and congenital anomalies of the coronary circulation account for most of the cardiac deaths. Among National Collegiate Athletic Association athletes, the incidence of sudden cardiac death is 1:43,770 participants per year. In older athletes, unsuspected atherosclerotic coronary artery disease is the leading cause of cardiac events during exertion. Exercise can trigger events through mechanisms such as plaque rupture and ischemia-induced arrhythmias. The overall risk is low, amounting to 0.3-2.7 events per 10,000 exercise-hours in men.

If a heart attack is in your future it may well occur during exercise …

Sedentary men were 56 times more likely to have a cardiac arrest during exercise than at other times. Habitually active men had a much lower risk during exercise, but they were still 5 times more likely to have a cardiac arrest during exercise than at other times. However, men who exercise regularly had a 60% lower overall risk of cardiac arrest than did sedentary men.

It doesn’t take a lot of exercise to gain most of the health benefits

A 15-year study of 55,137 American adults reported that runners enjoyed a 30%-45% lower risk of all-cause and cardiovascular mortality and a 3-year life expectancy benefit as compared with nonrunners. Even running for 5 to 10 minutes a day at a pace over 10 minutes a mile was beneficial. Protection was maximal at about 150 minutes of running per week

But some of us are prone to obsessive behaviours, A study …

evaluated 204,542 Australians ages 45 to 75 years. Over a follow-up that averaged 6.5 years, there was an inverse relationship between the amount of moderate-to-vigorous activity per week and all-cause mortality. As compared with sedentary individuals, those who performed 10-149 minutes of exercise per week exhibited a 34% reduction in mortality; 150-299 exercise minutes per week was associated with a 47% reduction in mortality, and levels of 300 minutes or higher with a 54% lower mortality rate. In all categories, intense exercise was somewhat more beneficial than similar amounts of moderate exercise. No harm was reported even with the largest amounts of intense exercise.

No sign of a J curve in that study but Marathons are not obligatory.

And now for something lighter …

Burning Matches …

Training is of benefit because of the response it engenders. Exercise at a greater intensity than the body is used to (overload) will produce some minor muscular mayhem that will be followed by repair and restoration (adaptation) leading to a greater capacity for future exercise (increased fitness).

There is considerable science to support all this for which we are indebted to an unbelievably large number of athletes who are prepared to exercise to exhaustion while breathing through masks and surrendering muscle biopsies at intervals.

Not everyone responds to the same extent or in the same way to training and there are way too many variables to formulate a precise prescription for the best of all training plans. The gap between Sports Science and Sports Coaching is the realm of Art.

I think it’s a very reasonable assumption that more is better, until more is too much. You’ll know where the boundary is after you cross it.

Endurance events are completed (by and large) at a rate at which oxygen supply keeps pace with fuel consumption except perhaps for the last hundred meters or so. In order to improve that pace it has been the practice of many athletes to train at the very boundary of aerobic/anaerobic metabolism. A growing body of coaches believe that this is too high a risk for the rewards it brings. The same risks are there for the enthusiast but the rewards don’t include gold medals.

The currently fashionable answer is polarised training. It’s a combination of a lot of Long Slow Distance with a little very high intensity mixed in. The middle intensity around the lactate threshold is avoided.

The suggested mix is 80% LSD and 20% high intensity. The true believer measures this out with a stopwatch and a power meter. The less obsessed can simply burn a match on a hill or two or try for a personal best on the next Strava segment on their morning ride.

MAF …

I watch a bit of Youtube from time to time and among the offerings that Google thought appropriate for me was a video about MAF. I found myself watching a middle-aged Canadian waxing lyrical, well repeating himself enthusiastically at least, about his running. We had a bit in common. He had once been a fairly familiar weight, he had been in and out of an exercise regime, had run a marathon even but just couldn’t get it all to stick. I had gone through that phase in my middle age, too, although I was on the way down from a more athletic youth and I think he was on the way up but not quite getting it to fly.

No matter, now he was here to tell me that he’d just completed a thousand miles of running under the MAF method, he was certainly saved and we all could be too.

I didn’t get all the way through the video but I gave him a thumbs up, anyone who runs a thousand miles deserves at least that much encouragement, and googled the MAF method.

It’s the brainchild of one Dr Phil Maffetone. MAF is short for Maximum Aerobic Function although I suspect that its choice as a handle had much to do with it being the first three letters of his idol’s name.

There is nothing particularly original in the method. It’s a combination of Long Slow Distance, sensible diet, sleep and stress management wrapped in some slick promotion. Having said that though if I was middle-aged again and inclined to run it’s a method with much to commend it.

Before getting to the core of the process I can’t resist this little quote from Dr M …

What’s the best heart rate for aerobic training? The answer to this is individual, and key to building a great aerobic body. Many are familiar with the old heart rate formula: 220 minus your age, multiplied by 65% to 85%. But this method has no scientific or clinical basis.

So for you Dr Maf  suggests training at a heart rate no greater than 180 minus your age, plus or minus a small fudge factor based on a very crude measure of your current health and fitness! What could be more scientific or clinical than that? Should your heart beat too quickly stop running and walk until it behaves more decorously.

Dr Maffetone is also a keen proponent of regular testing in the form of timed runs once again staying within the prescribed heart rate range.

The great virtues of the method, and yes there are virtues here, are that niggling injuries and fatigue are minimised and the fuel burnt will be biased towards fat. Improvement in fitness, especially if you’re coming off the couch, will show in greater pace while running at the chosen heart rate. I’m sure that greater rates of improvement are possible if you push harder, but pushing very hard is a high risk strategy. This is not a method that will generate champions but it’s better to be a mediocre runner than a former runner.

In my experience the hardest part of running is getting changed and out the door. Once you’ve achieved that the rest is easy. So easy in fact that you may become over zealous and forget that you need to do it again tomorrow.

Will I be incorporating this approach in my cycling?

By the time I’ve deducted my 71 years from 180 there isn’t enough wriggle room to get over the nearest hill. Someone would have to follow with my wheel chair. So no,  I will continue to burn a match or two on every ride.

 

 

 

Gonna be crowded in Texas …

The morning bike ride took the McGees to the pleasant little town of Avoca. The Sunraysia Highway runs right through the main street. Three caravans passed us as we drank a takeaway coffee. Escapees from colder climes, the first we’ve seen in a while.

A lot of Victorians head north for the winter, a lot of Victorians have had to rethink their plans. That includes us. Mildura is Victoria’s warmest and sunniest town and that might well have been the destination of today’s convoy but it’s no substitute for Queensland where the border remains closed to us leprous southerners.

Texas, NSW is a little town just south of the Queensland border and just about as far north as a Victorian can presently get. They’ll need a refugee camp there before long.