Archive for Did You Know?, exercise research
As you may have recently read in THIS ARTICLE from the New York Times, a recent review of 30 studies – published between January 1990 and March 2012 – regarding exercise interventions in children shows that for the most part, all of our efforts have been in vain. While the interventions were well designed and implemented, and may even have produced some initial positive results, at the end of the day (and more importantly, at the end of the interventions), kids really weren’t moving more.
You can check out the full review HERE.
My question to all of you is, where are we going wrong??
Formal interventions (e.g., Michelle Obama-led Let’s Move!) clearly aren’t working, but educating adult parents about the importance of exercise doesn’t seem to be working either. I think it’s pretty well-known at this stage of the game that childhood obesity increases the likelihood of being overweight or obese as an adult. Knowledge just isn’t power in this case.
The NY Times article posits a change in environment and an adjustment in the time of the interventions as potential solutions, but I’m curious to hear other ideas – so bring ‘em on!
We all know where the research usually stands on stretching: Right smack in the middle of nowhere.
There is little evidence that stretching of any type reduces injury risk; some evidence that static stretching may decrease power output in the lengthened muscles (though possibly not in explosive muscle actions lasting less than 100 milliseconds…); and the optimal modes of frequency and progression are still unknown.
The 2011 ACSM guidelines state that “flexibility exercise is effective in improving joint range of motion when performed at least 2-3 days per week, with the greatest gains occurring when stretching is done daily to the point of discomfort (but not pain);” HOWEVER, a more recent study in the NSCA’s Journal of Strength and Conditioning Research suggests otherwise.
In this particular study, authors tested joint range of motion at the hip after stretching either daily or three times per week, and either once or twice per day. After eight weeks, they found that hip ROM was increased equally in people who stretched daily and those who stretched only three days per week but TWICE on those days.
Conclusion: Three days per week of stretching may be as beneficial as daily stretching, provided the stretches are performed twice on those three days.
This may be good news for people with hectic schedules, and those used to stretching before and after a three-day training split. As always, one study doesn’t tell us much…But with stretching, thousands of studies haven’t told us much either! So we might as well try the protocol for ourselves if it’s a better fit for our lives. The one thing we do know is that anyone who needs to increase joint ROM will likely benefit from some stretching than none at all.
Ever wonder why you seem to perform better at a particular time of day? Or whether or not you should be exercising in the morning or evening? A recent review of research on the matter may help you answer these questions.
An article in this month’s Journal of Strength and Conditioning Research suggests that there may, in fact, be an optimal time to train – at least for some types of exercise. Without belaboring the science too much, the consensus in the literature seems to be that high-intensity, short-duration exercise that relies heavily on neuromuscular efficiency (e.g., sprints, jumps and other power movements) is best performed in the afternoon or early evening for optimal performance.
It isn’t completely clear why this is, but we think it may have something to do with the fact that the natural circadian rhythm of core temperature results in a passive warm-up effect at this time, enhancing metabolic reactions, increasing extensibility of connective tissue, reducing muscle viscosity and increasing conduction velocity of action potentials (that is, the speed at which our brains can tell our muscles what to do).
What does it mean for you? If you’re [not Usain Bolt...] training for power or neuromuscular efficiency, you’ll probably get better results if you train in the afternoons. BUT, according to the review, regularly training in the morning can improve typically poorer morning performances to the same (and possibly greater) level as the peak observed later in the day. So if you have some type of power competition that will take place in the morning, training in the morning is probably your best bet for success on that day. Not sayin’ you’ll beat the fastest man alive…but you may get slightly closer to a PR.
Similarly, strength training adaptations seem to be greater at the time of day at which training is typically conducted. Interestingly, training in the morning produces favorable performance in both the morning and evening, whereas evening training sessions do not seem to have the same carryover to morning performance.
As for the consensus on the effects of time of day on aerobic training…well, there isn’t one. As far as we can tell, it’s mostly individual. But something tells me we’ll keep looking for any edge we can get.
That said, bring on the Olympics!
It’s thought to be a survival mechanism: The more energy we can extract from food, the longer it will sustain us. Thanks to Brent for sending me THIS ARTICLE, which discusses research showing that cooking food increases its energy value.
Sounds crazy, but researchers from the University of Tokyo have created a pair of digitally-enhanced goggles purported to alter your sense of sight so that food appears larger than it actually is.
When put to the test, subjects wearing the goggles ate 10 percent less of a cookie than those not wearing the goggles. On the flip side, when they made cookies look smaller, subjects ate 15 percent more.
The scientists have also created and tested headgear that makes food look more appealing and smell sweeter.
Check out the story HERE.
Whether you know it or not, this is a very exciting time in physiology labs. There’s a great article in this month’s Fitness Journal from IDEA that highlights a plethora of new research showing just how much our genetic makeup actually affects our response to exercise – and not just in terms of weight loss.
For example, strength training may produce muscle gains ranging from 0% to 59% – depending on the number of satellite cells (i.e., stem cells that circulate in the bloodstream and help repair muscle tissue) that a given person has.
Cardiovascular training responses among individuals have also shown to vary from a 0 ml/min to a 1,000 ml/min improvement in oxygen transport after 20 weeks of the same protocol.
And as far as sedentary weight gain is concerned, some individuals put on 10 lbs. while others pack on 30 lbs. after being overfed by 1,000 calories per day for 100 days. Abdominal fat gain can range from 0% to a whopping 200% increase during this same time period. Wild!
So what does this mean for our exercise programs? Well, we obviously don’t have the technology to tell us how well our genes are likely to respond to a certain type of training (yet). But given the evidence of inherent variability in individual response, we have even more reason to stray away from a purely scientific “one size fits all” approach to exercise and pay closer attention to what happens when we put our programs into practice. What’s worked for us in the past may be the best indicator of what’s likely to work in the future – but only for us.
…or so thinks Bobby Hinds, according to THIS CBS NEWS STORY (fast forward to about minute 1:50 in the video).
I had the pleasure of meeting Bobby a few years ago, when he was first embarking on the idea to develop a device that would measure the amount of resistance his Lifeline users were lifting. But it looks like we might soon be in for a lot more fun than that!
I guess time will tell…
I hate to beat everyone to death with the stretching research on here, but this study is just way too cool not to discuss.
We’re in no position to say what’s right or wrong regarding stretching, but this particular study suggests static stretching could actually increase strength – in both the stretched AND contralateral muscle!
In short, researchers found that without any resistance training, statically stretching one calf led to a 29% increase in strength in the stretched calf, and an 11% strength increase in the NON-STRETCHED calf of untrained individuals. Wild!
They attributed the findings to neurological stimulation (Remember: A large part of strength is due to neurological adaptations, particularly in the untrained.): Passive stretching activates afferent activity and increases neural output of the muscle spindles, resulting in both increased strength AND a crosstraining effect.
What the heck does this mean?!?! In laymen’s terms, if you have an injured arm or leg that you can’t train, simply stretching the healthy one may help you maintain its strength – at least the part derived from neural components.
Now THAT is cool.
The recent discovery of the FTO obesity gene revolutionized the way we look at the human body, especially when it comes to weight. But maybe we shouldn’t have let it change our views quite so much…
THIS META-ANALYSIS shows that even if you have the FTO gene that predisposes you to obesity, exercise can reduce the effects of this gene in adults by as much as 30%.
We’re finding more and more that most conditions are the result of an interaction between genes and the environment. That is, the presence of a certain gene is required in order to have the condition, but that gene must still be turned on or off by some environmental factor (e.g., diet or exercise, or lack thereof…) in order for the condition to manifest itself. It appears the same is true of obesity.
While genetics and good nutrition will always be the backbones for healthy levels of body fat, exercise does play a significant role in the development of obesity in adults.
So make like Jeremy Lin and get moving!
It’s sad that health isn’t motivation enough and it takes financial incentive to get people to exercise, but I have to admit that Gym-Pact.com is a good idea.
How does it work? Here’s an excerpt from a recent New York Times article that explains the gist:
For starters, you need to have an iPhone to use the service, though it will soon be available on Android and HTML5 devices.
When you sign up, you’ll need to decide how many days a week you want to go the gym, along with what sort of penalty you will be slapped with if you’re too lazy to get there. You need to commit to at least one day a week for 30 minutes, with a minimum penalty of $5 for every missed visit. Gym-Pact’s average user commits to three days a week.
How does it know if you show up? Given that your smart phone knows where you are at all times, it also able to track if you’ve hit the gym. Gym-Pact has more than 40,000 gyms in its database — or more than 70 percent of gyms — and they said you can easily add your own (as long as it’s not a workout room in, say, your basement).
Once you’ve downloaded the app to your phone, you hit the check-in button every time you arrive, and it will confirm your location. And if you leave before the required 30 minute workout, you’ll get an audible pop-up warning you that your workout will be canceled if you don’t go back and sweat it out for full visit.
If you fail to get to the gym altogether, the credit card that the company keeps on file will be charged $5 per visit (or more, if you raised the stakes above the minimum).
But if you do satisfy your agreement, you will be rewarded with cash, which comes from your lazier peers who did not meet their commitments. The money is funneled into a PayPal account, and you can withdraw your winnings once they reach $10 (the company deducts a $1 fee every time you pull money out, though they may eventually charge a percentage of your earnings).
So, what you actually end up earning depends on how much other people slack off, and how many times you don’t.
I doubt anyone will put themselves in a position to pull a Hostess and file for bankruptcy (maybe a good sign for America??), but still not a bad idea for self-aware, financially-driven people with no motivation to exercise. I suppose it’s kind of like having a trainer: Once you invest money in your workouts, you’re a lot less likely to miss them. Not sure I agree with exploiting other people’s sloth, but if getting paid actually gets more people moving, I’m all for it. Of course, I’d rather them just pay me to make them sweat!