I'd be interested to see the difference in "forced" versus "high intensity" exercise. What if the animals are forced to run at a much lower pace than they prefer? Do we get the same results?
My guess is that the forced part of this has little to do with the effects. It's the increased intensity that is providing benefits.
I was curious about this as well, and the abstract from the study said:
"voluntary wheel running is characterized by rapid pace and short duration, whereas forced exercise involves a slower, more consistent pace for longer periods of time. This basic difference between the two forms of exercise is likely responsible for their differential effects on brain and behavior."
It also did say that both groups ran the same distance, but the non-forced rats did it in more sessions and a faster pace.
I think that in order to understand the nature of "forced" vs "voluntary" in this instance, you may have to consider how the rats normally cover distances. Humans, unlike most mammals, are designed to run for longer periods of time. Sorry if it's already been said.
No kidding. The emphasis on forced made it a little confusing. It seems extremely likely that the "forced" can be internal. When I'm at CrossFit, the criteria of the workout force me to exert much more strenuously than I'm comfortable with.
> In one study from 2008, rats forced to run wound up with significantly more new brain cells after eight weeks than those who ran when they chose, even though the latter animals ran faster.
ha, when I read that article all I had in my head was images of me doing death-by burpees and thinking "... I hope there are health benefits to that, because it really hurts..."
I think the idea is that what you want to do differs from what you are doing, or what you must do. When you run faster than you're comfortable with, the will to do that comes from yourself. External forced, not using your willpower.
I am not an exercise physiologist, however, moving people from an inefficient noodling cadence of 60 rpm to a highly efficient 90 rpm may have played a role in shaping the results.
As any cyclist knows, over the long term, 90 rpm's is far more comfortable than 60 and it is my understanding that 180 strides per minute (i.e. 90 with each foot) is also optimum for distance running.
Most amateur runners don't hit close to 180 spm unless they are barefoot runners. The general idea around a shorter stride for amateurs isn't about efficiency, as I understand it, but about injury prevention. Smaller strides means less time flying in the air, less mass displacement, and a softer landing.
edit:
that doesn't mean you aren't right about professionals doing it for efficiency reason, I just don't know.
The faster cadence is technically less oxygen efficient, but since oxygen is not the limiting factor, that doesn't really matter. The reasons cyclists pedal at a fast cadence is because it uses the aerobic system more heavily than the anaerobic system, and the aerobic system is easy to keep "on" for a long time. You breathe harder, but your legs never hurt.
(I decided to start following this advice a few months ago. A 30 mile ride in 2.5 hours at 75-80rpm used to tire me out. My first 40 mile ride at a high cadence (95 rpm) took the same amount of time but I wasn't even close to being tired. My usual "training rides" of 20 miles take almost no effort unless I make a conscious effort to go anaerobic for a few minutes at a time.)
That's a lot more individual than the aggregate study results generally indicate. I'm a cranker, not a spinner, and I used to do 250 miles/week -- that included a "century Sunday" -- with little fatigue (no more than I was looking for, certainly). Most of the folks with me would be turning at about 150% of my rate at any given point. I tried the 90 cadence, and it just didn't work for me; I'd get pooped over a piddling 20-miler, and never really improved in endurance.
When we race we adjust stride depending on the terrain- short strides on uphills level out the incline, and long strides on downhills let gravity take over and do the work for you.
YMMV (obviously), I find long strides going downhill far too damaging to my body. I practically fight gravity going downhill the way I do going uphill.
How are you forced to produce power output on a tandem bicycle? You can force the cadence but what happens if you just relax and let your legs go around with the pedals? I would think you would be producing zero power on your own, not exactly a grueling forced workout, or am I missing something?
Read the NYTimes article... you learn that the two sets of pedals are 1:1 connected. Your partner pedals faster and you have to pedal faster. Maybe not harder - but you do have to keep pace.
Maybe we should design an exercise bike with motor, and you just put your feet in the pedals and let them roll around without applying any force yourself? Seriously, a fast cadence on a bike isn't even work if you're not applying any force yourself.
Alviva was wondering why the people on the back were not slacking. MediaBehavior says they were only pedaling faster, not necessarily harder. I'm pointing out that the article clearly says they were pedaling harder.
Wankerish speculation: Involuntary exercise may tell the body that it needs to work smarter, not harder. Hence, more brain cells. In prehistoric times, it would be a warning signal that risk of death or is elevated. In a world of few calories, the body must prioritize, and relies on certain signals to set priorities. Voluntary exercise doesn't indicate nearly as much danger.
Is it the "forced" part that yields results, or the simple fact that it was more exercise? The article said they were forced to go at a speed faster than what they were comfortable with, yet the rodent study had them forced to go slower than their natural pace, with better results. A follow up study forcing people to go slower than usual would be interesting.
I think it matters more if you are cognitively present for the exercise, rather than the intensity of the exercise. It doesn't matter if you go fast or slow, it only matters that you are doing something you're not used to and as a result actively think about it when you are doing it.
For example, writing with your left hand if you are right handed may be an equally effective method of achieving similar cognitive results.
One well worn piece of advice from health fitness trainers has always been to vary up your routine. I think this is the key to making sure you work out different muscle groups, but also a way to keep your mind engaged.
My hunch is that this is partially what's going on in the study.
I agree with the basic hypothesis. Though wonder how it can be measured. I know my preferred term is awareness, but neither is it any more measurable. My experience suggests two tasks at a time is a reasonable substitute to make sure you are aware. For ex: counting the steps while running
I agree. It probably invokes an element of awareness, that primal "oh, shit, I need to start working or else." It's probably that fear which provides certain types of endorphins and brain activity you wouldn't otherwise get.
In Parkinson's disease equilibrium is usually very impaired, yet from this article apparently the subjects are still able to ride bicycles. I wonder how big of a confounder that is, or perhaps it's patients in very early stages of the disease, or relatively young. Having an elderly patient risk falling from a bike or a forced-effort threadmill machine doesn't seem to me like a reasonable risk to take. What other forms can this forced exercise take? Swimming, running on sand, these can be taxing but how do you incorporate the "forced" factor in?
Parkinson's is an auto-immune disease, so other approaches involve trying to minimize immune responses, via diet. Apparently ketogenic diets have also been used with varying degrees of success.
My father has Parkinson's so I know a bit about this topic. The positive effects of bicycling on motor control are relatively well-known and there is special equipment available. Mostly, it's tricycles modified to accomodate a person with disabilities.
They are fairly hard to fall off of. The only downsides are cost and storage. They usually run upward of $2k and take more space due to the 3D factor.
The article says that they're on the back of a tandem - a two person bicycle. As long as they're not completely leaning all over the place, the person in front should be able to keep things under control.
Well, if this really does pan out, then I'm sure you can rig some sort of harness on the patient while they're on a forced treadmill. When they start falling/losing balance, the harness gets yanked, pulling the patient off the ground. Basically, like a belaying system, except on a treadmill.
Is the forced part even necessary? It says the people were pushed harder than comfortable. You don't necessarily need someone cracking the whip to do that, especially with that kind of thing hanging over your head.
"You don't necessarily need someone cracking the whip to do that..."
You'd be surprised. Long-term goals are notoriously bad at motivating most people in the short run (hence, why procrastination is such a powerful force). So, even if you have the specter of something like total physiological degeneration looming over you, you're still going to work only to the brink of your comfort level unless someone pushes you further.
Anecdotal, but: I broke my arm a few years back in a really bad fall. Totally shattered a few of the bones in my right wrist (and I'm right-handed). Got a metal plate put in, and went through a year of physical thereapy. At the outset of the PT, I was told in no uncertain terms that I'd never regain proper movement of my right hand unless I worked my ass off every day at range-of-motion exercises -- which, at the time, were extraordinarily painful. So, in theory, sure, I could do them at home and never actually go in for PT. But whenever I did that, I'd work up to the edge of my comfort level, but never go past it. Conversely, when I went in for PT, having someone there to "crack the whip" pushed me past that discomfort threshold, and that's how I broke through the plateaus on the path to recovery.
The body's (and mind's) natural inclination is to avoid pain and discomfort, so you trick yourself into thinking you're working as hard as you can when you're actually not. And exercise isn't about working as hard as you can; it's about working harder than you can. That's where the progress happens.
I suppose the question is over the nature of forced.
I have a rowing machine which gives me a readout of speed/distance/cadence etc.
I 'force' myself to maintain a certain speed for a certain time even when it is quite uncomfortable. Is that sufficient for the 'forced' effect to come into play. I suspect it is.
Do you work out to the point of muscle failure? Do you maintain a speed so grueling that you literally can't row at all after a certain point? That's my interpretation of "forced," at least as experienced in my PT. Granted, I don't know what "forced" meant in the context of the study being talked about in this article. Accordngly, I can only guess at it. (No desire to play "No True Scotsman" on this, I assure you.)
In the article they said they tested them and if you went around 60 RPM on the bike the forced part was at 90 RPM. So they could measure swim pace then have them train at a higher pace.
From the article: "These findings are exciting, Dr. Alberts says, because they contrast with some earlier results involving voluntary exercise and Parkinson’s patients. In those experiments, the activity was helpful, but often in a limited, localized way. Weight training, for instance, led to stronger muscles, and slow walking increased walking speed and endurance. But such regimens typically did not improve Parkinson’s patients’ overall motor control... The forced pedaling regimen, on the other hand, did lead to better full-body movement control"
"In one study from 2008, rats forced to run wound up with significantly more new brain cells after eight weeks than those who ran when they chose, even though the latter animals ran faster. "
This earlier study's conclusion that the forced aspect was more important than pushing the exerciser outside of their comfort zone. It seems like they should experiment with 45rpm forced exercise to see if that has the same effect. Though, it may have been just the article making that logical jump.
I'm curious to find out if what they're trying to isolate is "discipline." I'm not talking about the colloquial definition of discipline but rather exercising the ability to do what's best even if it's not convenient.
I'm talking about the foresight of the intellect over the mind and body. Often times, when we rationalize things or activities just become habits, the mind and body passively agree. I'd argue that's not actually practicing discipline anymore since there's nothing within ourselves (mind & body) to fight.
I'm by no means an expert, but from my reading of body hacking and dieting etc, it seems that higher intensity workouts lead to increased cortisol release, a hormone released in response to stress. I'm not sure if this is the hormone they're referencing though, because IIRC extended periods of elevated cortisol levels are associated with Parksinson's/Alzheimers...
From what I understand, high-intensity workouts do raise cortisol but only temporarily. Long-term, exercise-induced adaptations counteract those raised cortisol levels, and actually lower them.
It's pretty clear that "forced" in the context of the experiment is being physically forced to do more work, not being "forced" like being forced to eat your vegetables.
I think it has something to do with external energy being added, and the subject not having control over the speed.. I don't know if a treadmill really meets this criteria. I think you would have to be physically strapped into the treadmill :P
Honestly, this seems like one of those experiments which, in retrospect, provides obvious results. Exercise is a net positive for physical health. Why wouldn't forced exercise provide an additional cognitive/neurological health benefit in addition to the cardio/muscular benefits? I know this is a completely simplistic and unscientific opinion, but it seems to make sense.
Actually, I still find these sorts of results very surprising.
Till recently, I always thought that once one was an adult, one's brain lost its self-renewal capacity, and that progressive mental decline was inevitable. This was the general scientific view as well. [ http://en.wikipedia.org/wiki/Neuroplasticity ]
Probably because if you just do what you're comfortable with, you won't learn anything new. If you're forced to do something uncomfortable, your brain learns more about your body.
Makes sense. They mention other benefits to forced exercise too. I wonder if it is an evolved response to stress. Sort of: if the bear is chasing you your body responds differently to deal with later bears.
I don't think it's that complicated. I just meant learning different ways to move your legs: get your abs involved, pump your arms differently, etc. Parkinson's can make people "forget" how to walk even if they can still run. So learning how to move your body in different ways could help combat that. https://www.nytimes.com/2010/04/01/health/01parkinsons.html
My guess is that the forced part of this has little to do with the effects. It's the increased intensity that is providing benefits.