Tuesday 170509

 

The salt equation taught to doctors for more than 200 years is not hard to understand.

The body relies on this essential mineral for a variety of functions, including blood pressure and the transmission of nerve impulses. Sodium levels in the blood must be carefully maintained.

If you eat a lot of salt — sodium chloride — you will become thirsty and drink water, diluting your blood enough to maintain the proper concentration of sodium. Ultimately you will excrete much of the excess salt and water in urine.

The theory is intuitive and simple. And it may be completely wrong.

New studies of Russian cosmonauts, Read more Tuesday 170509

Let’s get our Box Squat on

The toll that aging takes on a body extends all the way down to the cellular level. But the damage accrued by cells in older muscles is especially severe, because they do not regenerate easily and they become weaker as their mitochondria, which produce energy, diminish in vigor and number.

A study published this month in Cell Metabolism, however, suggests that certain sorts of workouts may undo some of what the years can do to our mitochondria.

Exercise is good for people, as everyone knows. But scientists have surprisingly little understanding of its cellular impacts and how those might vary by activity and the age of the exerciser.

So researchers at the Mayo Clinic in Rochester, Minn., recently conducted an experiment on the cells of 72 healthy but sedentary men and women who were 30 or younger or older than 64. After baseline measures were established for their aerobic fitness, their blood-sugar levels and the gene activity and mitochondrial health in their muscle cells, the volunteers were randomly assigned to a particular exercise regimen.

Some of them did vigorous weight training several times a week; some did brief interval training three times a week on stationary bicycles (pedaling hard for four minutes, resting for three and then repeating that sequence three more times); some rode stationary bikes at a moderate pace for 30 minutes a few times a week and lifted weights lightly on other days. A fourth group, the control, did not exercise.

After 12 weeks, the lab tests were repeated. In general, everyone experienced improvements in fitness and an ability to regulate blood sugar.

There were some unsurprising differences: The gains in muscle mass and strength were greater for those who exercised only with weights, while interval training had the strongest influence on endurance.

But more unexpected results were found in the biopsied muscle cells. Among the younger subjects who went through interval training, the activity levels had changed in 274 genes, compared with 170 genes for those who exercised more moderately and 74 for the weight lifters. Among the older cohort, almost 400 genes were working differently now, compared with 33 for the weight lifters and only 19 for the moderate exercisers.

Many of these affected genes, especially in the cells of the interval trainers, are believed to influence the ability of mitochondria to produce energy for muscle cells; the subjects who did the interval workouts showed increases in the number and health of their mitochondria — an impact that was particularly pronounced among the older cyclists.

It seems as if the decline in the cellular health of muscles associated with aging was “corrected” with exercise, especially if it was intense, says Dr. Sreekumaran Nair, a professor of medicine and an endocrinologist at the Mayo Clinic and the study’s senior author. In fact, older people’s cells responded in some ways more robustly to intense exercise than the cells of the young did — suggesting, he says, that it is never too late to benefit from exercise.

Cindy + Box Jumps

Why calorie counting is almost useless and often misleading

Petros Giannakouris / AP
“A new study says taking a hot bath burns as many calories as a 30-minute walk.”

That popped up in a tweet from Time on Tuesday night. It referred to a small investigation into the physiologic effects of heat exposure.

The responses on social media were an inevitable, exultant mix of self-identification and self-deprecation. Things like, This is so meeeeee, and Guess I’m right for not going to the gym, suckers, and Fill ’er up (the tub) I’m taking a bath forever and going to eat the whole time [gluttonous emoji].

And, of course, This is a distraction from the Russia scandal.

We are all constantly projecting meaning onto the world to suit the templates we’ve committed to, so I saw the study’s finding as an indictment of calories. My own reply was that the study serves to prove that calories are “an almost useless and often misleading metric.”

My tweet was popular and beloved by almost everyone. Read more Cindy + Box Jumps

I Still Hate Burpees

From Runner’s World

I Did 30 Burpees For 15 Days and Here’s What Happened

They’ve been called the most efficient exercise known to humankind, and doing them every single day was more rewarding than I could have imagined.

MONDAY, MARCH 20, 2017, 10:29 AM
doing a burpee
PHOTOGRAPH COURTESY OF DANIELLE ZICKL
When I wanted to try CrossFit, I dragged one of my best friends to a beginner’s class with me. And although she was a good sport about it, she mentioned on our drive home how the deadlifts-crunches-burpees circuit would have been so much better had it been just deadlifts and crunches.
I was shocked. To me, the burpees were the best part. It was then that I realized not everyone is as crazy as I am—not everyone enjoys burpees. This got me thinking: What if I incorporated burpees into my daily routine?

I did some digging into the origin of the exercise, and I found out they were created in 1939 by a man named Royal H. Burpee to determine a person’s physical fitness. Back then, the move didn’t include a pushup in the middle or the jump at the end, but it was still dreaded.

First, I wanted to make sure my form was on point. I decided to do the modern burpee, not the old-school version from the 1930s.

I read some how-tos. To do a burpee, start from a standing position, then squat down and place your hands on the floor in front of you. Quickly kick both feet out behind you so you are in a pushup position, and then do one pushup. Next, bring your legs forward to go into a squatting position again, and jump up.

Yes, it’s an awkward, frog-like movement. But I knew it would be worth it to challenge myself.

I’ll admit I’m not great at sticking to things. I always have the best intentions, but when life starts to get busy, I’ve been known to make excuses here and there (I’m working on it, I swear). I was glad I had this story to hold me accountable as I set out to become a burpees beast.

So with my trusted 50 Cent Pandora station by my side, I got to work.

Here’s what I did:
I completed three sets of 10 burpees for 15 days straight. I started out with a one-minute rest in between my sets and decreased that time by 15 seconds every three days until I was doing all 30 burpees at once with no rest for the last three days.

I wanted to stick to the same time every day—when I woke up at 7:30 a.m.—but that didn’t always work out. When I slept in, I’d do a circuit when I got home at around 4 p.m.

Here’s what happened: 

1. My running improved.
My typical easy pace is about nine minutes per mile, but towards the end of the 15 days, I started running faster without consciously ramping up my speed. My lungs felt clear and I coasted through miles.

I was also going longer. I’ll Read more I Still Hate Burpees

Why Exercise Is Good for the Heart

 CreditGetty Images

Even a single workout could be good for the heart. That’s the conclusion of a fascinating new study in mice that found that 30 minutes on a treadmill affects gene activity within cardiac cells in ways that, over the long haul, could slow the aging of the animals’ hearts.

Although the study involved mice,the results may help to explain just how, at a cellular level, exercise improves heart health in people as well.

There’s no question that, in general, physical activity is good for hearts. Many studies have found that people who regularly exercise are much less likely to develop or die from cardiac disease than people who are sedentary.

Still, researchers have remained puzzled about just how exercise alters hearts for the better. Exercise is known to improve our blood pressure, pulse rate and cholesterol profiles, all of which are associated with better cardiac health.

But many scientists who study the links between exercise and heart health have pointed out that these changes, considered together, explain only about half of the reported statistical reductions in cardiac disease and death.

Other, more complex physiological modifications must simultaneously be taking place within the heart itself during and after exercise, these researchers have speculated.

And recently, Read more Why Exercise Is Good for the Heart

Is Your Workout Not Working? Maybe You’re a Non-Responder

Research and lived experience indicate that many people who begin a new exercise program see little if any improvement in their health and fitness even after weeks of studiously sticking with their new routine.

Among fitness scientists, these people are known as “nonresponders.” Their bodies simply don’t respond to the exercise they are doing. And once discouraged, they often return to being nonexercisers.

But an inspiring and timely new study suggests that nonresponders to one form of exercise can probably switch to another exercise regimen to which their body will respond. And a simple test you can do at home will help you determine how well your workout is working for you.

One of the first major studies to report the phenomenon of nonresponders appeared in 2001, when researchers parsed data from dozens of previously published studies of running, cycling and other endurance exercise.

The studies showed that, on aggregate, endurance training increased people’s endurance. But when the researchers examined individual outcomes, the variations were staggering. Some people had improved their endurance by as much as 100 percent, while others had actually become less fit, even though they were following the same workout routine.

Age, sex and ethnicity had not mattered, the researchers noted. Young people and old had been outliers, as had women and men, black volunteers and white. Interestingly, nonresponse to endurance training ran in families, the researchers discovered, suggesting that genetics probably plays a significant role in how people’s bodies react to exercise.

Since then, other researchers have found that people can have extremely erratic reactions to weight training regimens, with some packing on power and mass and others losing both.

And a study published last year concentrating on brief bouts of intense interval training concluded that some people barely gained endurance with this type of workout, while others flourished, greatly augmenting their fitness.

These studies, however, were not generally designed to tell us whether someone who failed to benefit from one form of exercise might do well with another.

So for the new experiment, which was published in December in the journal PLOS One, researchers from Queen’s University in Kingston, Ontario, and the University of Ottawa decided to focus intently on whether a nonresponder to one form of exercise could benefit by switching to another.

They began by gathering 21 healthy men and women and determining their VO2 max, a measure of how much oxygen the lungs can deliver to the muscles; heart rates; and other physiological parameters related to aerobic fitness.

Then they had each volunteer complete two very different types of workouts. Each training regimen lasted three weeks, and the researchers waited several months before starting the next regimen, so that volunteers could return to their baseline fitness.

One three-week routine involved typical endurance training: riding a stationary bicycle four times a week for 30 minutes at a moderately strenuous pace.

The second type of exercise revolved around high-intensity intervals. Each volunteer completed eight 20-second intervals of very hard pedaling on a stationary bicycle, with 10 seconds of rest after each bout. The intervals were brutal but brief.

At the end of each three-week session, the researchers again checked each volunteer’s VO2 max and other fitness measures.

As a group, they had gained admirable amounts of fitness from both workouts and to about the same extent.

But individually, the responses varied considerably.

About a third of the people had failed Read more Is Your Workout Not Working? Maybe You’re a Non-Responder