2013-11-21

"The Most Important Type Of Fitness For Good Health Is Cardiovascular Fitness"

The study to which I linked in this morning's "Some Links" post is full of important information and deserves more thorough treatment than a "Some Links" post affords, but I wanted to get the information out there before taking some time to discuss it in greater detail.

The punchline of the whole matter is neatly summed up at Medical News Today:
Around the world, many children do not run as far or as fast as their parents did when they were kids, according to a large study presented at a scientific meeting in the US recently. 
The study concludes that today's kids are about 15% less aerobically fit than their parents were at their age. 
And in the US, kids' cardiovascular endurance has fallen by around 6% per decade between 1970 and 2000. 
The researchers warn that such a decline in fitness may mean worse health in adulthood.
One important piece of information here is contained in the story's first three words. BBC News adds that the study involved forty-six years of data that involved more than twenty-five million children in twenty-eight countries. So this is not just another "people are fat in the US" story. This is a story about a global trend toward lower levels of physical fitness.

How bad is it? Here's how USA Today puts it:
On average, it takes children 90 seconds longer to run a mile than their counterparts did 30 years ago. Heart-related fitness has declined 5 percent per decade since 1975 for children ages 9 to 17.
I readily concede that I was faster than average when I was a kid, especially when it came to running a mile. But for point of reference, I recall running something in the 5:40 range during an 8th grade fitness test. 90 seconds slower than that would be 7 minutes and 10 seconds or so. That would imply that the average "fastest male runner in class" is running at speeds that are much slower than even the fastest girls ran when I was a kid*.

To put this another way, I was in the top-ten of distance runners in my state during my senior-year season of cross-country; today, an equivalent runner would be a national champion.

If you're active across the "man-o-sphere," then you have probably heard the oft-repeated howler that strength training is a more significant boon to health and fitness than cardiovascular training. I hate it when people say this, because there is exactly zero evidence for this. Here's one excerpt from the MNT story (emphasis mine):
Dr. Tomkinson says while there are many ways that young people can be fit, like developing strength by lifting weights, being flexible like a gymnast or being skilled at tennis, this is not the same as having cardiovascular fitness, which is what most relates to health, as he explains:

"The most important type of fitness for good health is cardiovascular fitness, which is the ability to exercise vigorously for a long time, like running multiple laps around an oval track."
 And of course BBC adds:
To stay healthy, children and young people need to do at least an hour of physical activity - such as walking or cycling to school and running in the playground - every day. It can be done in small chunks rather than one session. 
Prof Michael Gwitz of the American Heart Association said: "The type of exercise is really important." 
He says exercise must be something that "makes you sweat" and is "sustained and dynamic" to promote cardiovascular fitness. 
Simply going to the gym or belonging to a school sports team might not be enough, unless you are moving around a lot.
In my "Some Links" post, I made a wry reference to the fact that health studies these days tend to be extremely self-serving. Almost every month, we get news of how coffee and red wine are health foods, how switching to the Italian Restaurant Diet is going to make you a centenarian (no, there's not really any such a thing as the IRD, but maybe I ought to create one and become a millionaire), how "all you need to do" at the gym is lift a few weights and do 20-minutes of HIIT twice a week, and you'll be "healthier" than a marathon runner and whatnot.

I have repeatedly insisted that this information is all an oversimplification that misses the key point. But I'm not just a contrarian who insists that running is the be-all, end-all. It's common sense. There's a reason you would rather spend 30 minutes on a Smith Machine than go running for 30 minutes, and that reason is not "because Smith Machines are a better workout." Quite the opposite.

The general rule of thumb is that if it doesn't kind of suck, then you're probably not getting much of a workout at all. You have to accept and understand this.

Look, being the next Ronnie Coleman is really, really cool thing to do. But it's not going to extend your life or make you a healthier person. It's just going to give you a lot of muscle mass. This might be what you want today, but I submit that the older you get, the more you will want to have been focused on cardiovascular health in your youth. You'll see what I mean when you start taking low-dose aspirin.

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* Of course, that's probably not an entirely fair comparison, since the fastest runners are probably about as fast now as they used to be. So, too, are the slowest runners likely to be about as slow as they used to be. I suspect the population mean has shifted 90 seconds to the right (i.e. slower), despite the outliers, of which I was most certainly one at that age.