A lot of comments are claiming this study shows that exercise is good for your health. Though I generally agree with that premise, that is NOT what the results of this study show. The abstract and visual abstract clearly state this.
- The RCT was done only on individuals aged 70-77
- Furthermore the results were not statistically significant at p < 0.05. You can see this in the visual abstract where the 95% CI overlaps with risk ratio = 1.0, where 1.0 means "no difference" between the groups.
Note that the results being non-stat sig does not mean that there was no difference! It means that the difference, if present, was probably too small to detect given the power (number of participants) included in the study. This is important to understand!
Furthermore, in the "Strengths and limitations of this study" they clearly outline some reasons why the results may have been non stat-sig, including:
- "Firstly, participants in the control group had a high level of activity throughout the study, and many exercised using HIIT. This might have affected the study’s ability to detect statistically significant differences between groups."
- "selection bias might have influenced our results, as participants were more active and had better overall health than non-included participants"
Basically, even the "control" group looked like they had a good baseline level of activity, decreasing the activity level difference between that and the two treatment groups.
My takeaway from this study is that in isolation, it doesn't provide much evidence for or against the effect of exercise, but taken together with other studies can be used for evidential value.
The results can also be used to inform future studies. The authors clearly understood this when they stated in the main measure outcome: "An exploratory hypothesis was that HIIT lowers mortality more than MICT."
Firstly, participants in the control group had a high level of activity throughout the study, and many exercised using HIIT.
I absolutely get why they had to use a control group that was decently in shape, otherwise the effect size compared to the sedentary would probably have been so massive as to be comical and uninformative. But…where are they getting 75-year-olds who are doing HIIT? Is Norway full of septuagenarian gym rats and cross-country skiers?
That level of baseline activity could explain why the MICT actually increased the all-cause-mortality risks. It appears the the mixed control group means that the MICT was actually reducing the average exercise intensity from the norm. What a frickin' overachieving set of septuagenarians (reminds me of Mr. Awesome in Chuck)! I'd assume if there were more "no/low" exercise group the MICT would appear much better. Tantalizing results though.
The control group wasn't assigned to do their regular level of exercise, but rather to follow an exercise routine based on the Norwegian government's existing recommendations. The authors expected a 10% 5 year mortality rate based on population-wide estimates, and their control group had a 4.7% 5 year mortality rate.
Still, going at 90% of your maximum heart rate repeatedly for two-three minute intervals is really hard work, at any age and shape.
And as others pointed out, the baseline group here is probably a force of nature unto themselves. 75-year old Norwegians were born into a poor country just starting to recover from war and occupation, where most people were farmers or fishermen. It was not until these people had been working adults for 10 years that Norway discovered oil and began its rapid economic growth, by that time these people were used to hard work.
Then you take that generation, and select the toughest portion out of those who say they are interested in participating in a scientific study on exercise, so a two stage selection of fit people.
Basically the baseline here consists of people who think hiking in the mountain for several hours is great fun, and that it's been a bad week if they have not done so twice.
> Basically the baseline here consists of people who think hiking in the mountain for several hours is great fun, and that it's been a bad week if they have not done so twice.
Isn't it like, almost everyone? Except possibility to do it twice a week. Most people I know think hiking in the mountain is great way to spend holiday and they are not particularly tough.
In seriousness, Nordic (cross country) skiing is an activity enjoyable well into old age. Having done a couple non-competitive “races”, I’m always amazed at the range of ages.
...Adorable old timers with perfect form just slowly gliding across the snow for hours.
There's also some potential for selection bias in the drop-out rates:
>The numbers of drop-outs after one, three, and five years of follow-up were 76 (19%), 104 (26%), and 132 (33%) in the HIIT group, 58 (15%), 76 (20%) and 101 (26%) in the MICT group, and 61 (8%), 95 (12%), and 156 (20%) in the control group.
In other words, the entire observed effect may be due to HIIT being better at making unhealthy subjects drop out of the study.
I think that's a valid point but it may not make a significant difference. Judging by the fact that the control group had a pretty decent drop-out rate it appears that the drop outs reverted to lower than average physical activity levels. I am playing devil's advocate here, but you can't rule out the hypothesis that trying a bit of HIIT convinced more people to take it easy at their age.
I think I see the point you are making now. If HIIT to a greater degree prompts less fit participants to drop out than in the other groups, it might skew the results.
Not really sure in what direction though. If it had been a study on the effect of HIIT vs less intense training on cardiovascular fitness, this kind of dropout would bias the results in the direction of HIIT. I have no idea of what effect it would have when the variably of interest is mortality.
- Control: followed the current Norwegian guidelines, which recommend 30 minutes of moderate level physical activity almost every day
- High Intensity Interval Training (HIIT): Generally followed the same program as control, but two of the five sessions were instead a 10 minute warmup, followed by four four-minute intervals, working at 90% max heart rate
- Moderate Intensity Continuous Training (MICT): Generally followed the same program as control, but two of the five sessions were instead a half hour of steady-state exercise, at about 70% max heart rate
Conclusion: There was little to no difference in mortality between the control, HIIT, and MICT groups.
I don't love this study design, because it isn't really testing HIIT (or MICT); it's testing what happens when 40% of your exercise is HIIT (or MICT).
That being said, I think the most important takeaway is that exercise is good for you, and what that exercise looks like is almost completely unimportant. Do what you enjoy and can sustain. If you have ten minutes in the morning, do HIIT. If you have an hour after work and want to get out of the house, go jogging or ride a bike. Anything is better than nothing.
It looks a bit like you’re quoting the conclusion of the study and saying there wasn’t much to conclude. But here is the actual conclusion, copied and pasted, in case people read your version and come away thinking it’s what the study actually concluded.
“This study suggests that combined MICT and HIIT has no effect on all cause mortality compared with recommended physical activity levels. However, we observed a lower all cause mortality trend after HIIT compared with controls and MICT.”
This is a scientific study, presumably posted because the poster believes we can read it and understand it. I’m not sure why it needs to have its conclusion rewritten and then some opinion based advice added.
I think the useful takeaway for Norway is that there is no evidence that they need to change their national recommended guidelines for physical activity.
That quote leaves out important context. They did not actually observe lower all-cause mortality with HIIT compared to the controls nor MICT, because both results were statistically insignificant.
They did observe lower all-cause mortality, just like they said themselves in their conclusion. They observed that, but were not able to safely conclude a causal relationship.
In particular, in the case of HIIT vs MICT they were within a percent or two of that 95% confidence. It is clear that further investigation is necessary, as it is quite a bit more likely than not that a causal relationship will be determined.
It is a good practice for scientists to not draw firm conclusions, nor for policy makers to adjust policy, for results that fail to meet that level of statistical significance. However, trying to shut down discussion and interpretation on that basis is neither helpful, nor productive.
I was reading a scientific paper on the efficiency of face masks based on a meta-study of other papers. My perosnal conclusion was a lot more uncertain than the conclusion that the paper came to.
Most of the evidence came from n95 respirators in hospital settings, while the "normal" medical mask evidence was a lot weaker. Yet their conclusion was to advise mask use for the general public (which is gong to be the normal masks, or cloth masks in the majority of cases) based mainly on n95 evidence.
Scientific studies are validly subject to inspection and comment. Just because the authors state something doesn't mean they've reached the correct conclusion, that the study was well designed, that there are not alternate explanations, etc. IOW, it's perfectly acceptable, and useful, to critique a scientific study. In fact, it's a cornerstone of the scientific method, practiced daily in research institutions.
Although these results are not exactly impressive or compelling (they don't make me want to change my exercise habits), it's reassuring to see researchers go through with publishing underwhelming results, rather than cherry-picking only the interesting results and sitting on the rest, which is a major contributing factor to the crisis of confidence/replication in the social sciences.
Why do you say that the results aren't impressive?
49% reduction in all cause mortality when High intensity interval training is compared to moderate intensity continuous training seems like a very strong result.
Mostly because they admit those results are not statistically significant (for example, at the bottom of the summary diagram). That said, I admire their honesty, and I hope these results suggest other kinds of experiments to other researchers. Maybe the study just needs to be larger, or longer.
Focusing on specific kinds of mortality might also give stronger results than measuring "all cause" mortality. I say that because it seems like cancer was the biggest killer in these groups. I am not a doctor, but I wouldn't have thought cancer was causally related to (lack of) exercise, the way cardiovascular diseases are believed to be. I'd be interested to see larger studies with enough non-cancer deaths to say something statistically significant about the effect of exercise on those outcomes.
They had 1567 participants. Compared to control (HIIT-like), HIIT reduced risk by 1.7% while moderate intensity training increased it by 1.2%. The overall mortality in the control group was 4.7%. For a controlled trial, that seems like a large number of participants (correct me if I'm wrong), they just were too healthy ;-)
I assume the significance problem is inherent to studies looking at mortality as the outcome is very binary and can take a long time to manifest. As an effect on all-cause mortality can be seen as the ultimate metric of how healthy something is, it's probably still worth it to investigate. In this case, they made it quite difficult for themselves by comparing active people to other active people.
It's also possible that they made other observations during the study that are or will be published separately.
Also, just adding some sugar to this, don't forget that this study was in Norway. Overall health levels would be higher than in, say, USA. I'm talking about weight specifically.
Assuming healthy / not overweight would be a very big assumption to make for the US (as a Norwegian I went to the the USA, once, in 1999, and what I saw there shocked me), where another study could be to monitor mortality outcome of getting weight under control and exercising vs not.
I'd also love to see impact of weight resistance training added to the mix surveyed.
And not just Norway, but specifically Trondheim. Correct me if I am wrong, but I expect their lifestyle to be even less sedentary than the average Oslo resident. I expect the results to have slim pickings (pun intended)!
Roger that. But even by e.g. Australian standards (which are a lot closer to the US ones), Oslo is far from sedentary; I didn't even think about buying a car in Norway before I left it, being happy to walk/run, ride or PT it everywhere. Bad diet, alcohol use etc is a lot more common than in Norway too.
I read that wrong. I thought that the overall mortality rate in the groups was 1.2% and 1.7%. Didn't realize those were both differences from the control.
Because running a large enough study is expensive and it's cost-effective to perform a smaller study to determine an approximate size of the effect. Then, you can design the next study to have enough power to distinguish the expected effect size from the null hypothesis.
Additionally, these results could be aggregated with comparable results to yield a stronger result.
"an absolute risk reduction of 1.7 percentage points was observed after HIIT (hazard ratio 0.63, 95% confidence interval 0.33 to 1.20) and an absolute increased risk of 1.2 percentage points after MICT (1.24, 0.73 to 2.10)."
So, 1.7% vs 1.2% seems just above noise level. The OP is right, the numbers are not that impressive.
We are not talking about reducing overall mortality by double digits...
Summary: looks like exercising is good, and adding HIIT has an increasing effect of reducing mortality, but the overall effect is small.
Those are absolute risk reductions, not relative ones. The 1.7 percentage point reduction equates to a 37% reduction in all cause mortality, and a 1.2 percentage point increase is a 25% increase.
Those are huge numbers. The problem is that the confidence interval is really wide.
Doesn't this also imply that the effect is "small" even if real? After all if there would be a very strong correlation (eg a true and exclusive casual chain) then we would see a huge signal even in small and noisy datasets. Or am I missing something?
No. If you look closely at the data you might be able to draw such conclusions but lack of statistical significance often doesn't suggest or imply a small effect. Notice that in this case in particular, the confidence intervals are consistent with very large positive or fairly large negative effects. Don't underestimate the amount of noise often found in studies. Lack of significance usually just means that data is too noisy to tell us anything. If you get significance you get to say: the data is probably not pure noise but the effect could still be very tiny or caused by systematic measurement errors. Null hypothesis testing is pretty useless really.
Thanks for your detailed reply! I meant that even this dataset puts a limit on the effect size, if viewed as an "evidence of absence of clear and large effect".
Of course since "everything is correlated" [0] expecting such truly simple signals might be nonsensical/pointless.
I was just lamenting the lack of simple magical treatments basically.
>Participants were randomised to two sessions weekly of high intensity interval training at about 90% of peak heart rate (HIIT, n=400), moderate intensity continuous training at about 70% of peak heart rate (MICT, n=387), or to follow the national guidelines for physical activity (n=780; control group); all for five years.
I can't quite tell by your summary whether you are saying "exercising is good, but the overall effect on mortality is small", or "exercising is good, and the effect of adding HIIT to baseline exercise is small".
You cannot make the former statement from this study as control group were not non-exercisers (and adherence was decent). The latter statement, does seem to be supported.
Regarding exercise in general, the literature shows the mortality gap between exercisers and non-exercisers is absolutely massive.
Slightly OT: I'm not sure I've ever seen a "Visual Abstract" before and I kind of love it. You can pack way more information into the same space and in a much more digestible format than a purely text abstract.
Two things that stuck out to me after reading the abstract:
* The control group wasn't "no exercise." It was "follow national guidelines for physical activity."
* Median age of study participants was 72.8 years.
Because of this, I'm not sure what this study actually means, other than "grandma should get more exercise." I suppose this is a fine study design, if you specifically want to study senior citizens, but it would be nice to have a much longer-term study on younger people.
Then, there's "Control participants chose to perform more of their physical activity as HIIT than the physical activity undertaken by participants in the MICT group. This meant that the controls achieved an exercise dose at an intensity between the MICT and HIIT groups."
It is perfectly reasonable for the control group to be following standard guidelines. In all medical trials, for example, the control group usually follows the current standard of care. Why does that stick out?
It sticks out at least in the US because "following standard guidelines" is not what most people do. Most people (at least in the US) hardly exercise at all, so a control groups that exercises 30 minutes a day is already a group that exercises a lot compared to the average person. I agree with you that its reasonable, but the study then teaches you about the relative merits of different kinds of exercise, rather than the effect of exercise compared to "no exercise" which is how people tend to think of a control group.
Yes, but I think the question motivating the study is "should we change standard guidelines?" and not "is exercise good?". Not least because exercise is very very good and rechecking that isn't a very high priority.
To be clear, the study actually does not show any statistically significant effect of exercise on mortality rate compared to the control group (it shows an improvement, it's just not statistically significant).
The verbatim conclusion they present is:
"This study suggests that combined MICT and HIIT has no effect on all cause mortality compared with recommended physical activity levels. However, we observed a lower all cause mortality trend after HIIT compared with controls and MICT."
Yep, from the article: "Control participants chose to perform more of their physical activity as HIIT than the physical activity undertaken by participants in the MICT group. This meant that the controls achieved an exercise dose at an intensity between the MICT and HIIT groups."
And, if you can't make yourself do a 10 minute walk every day, consider getting a dog, if your finances can support it. I walk an average of over an hour a day with my dog, and it's fun, because I have my dog with me. Normally, I probably wouldn't walk that much if I didn't have her.
The dog that could be living in your apartment is currently in a cage somewhere and will be killed (we say "euthanized") soon.
I don't say this to shame you or anyone into getting an animal. My only point is to argue that living in an apartment is not really so bad for an animal. If you're avoiding an animal for your own sanity while living in an apartment, that's fine, I do not fault you for it. If you're avoiding an animal for the animals sake, then I think the animal would prefer an apartment to a cage.
That is a very good point I failed to make. Before I adopted my dog, she was sharing a small room of around 100 square feet with another dog, and I don't think she ever got to spend any off leash time outside. Now, she has 10x the space, all to herself, and we go to the park every single day that it's practical to do so. She's undoubtedly happier than she was then; it's obvious just by looking at her.
The shelter I adopted from is a no kill shelter, but, keep in mind that "no kill" really means "fixed capacity." If the no kill shelters are full, guess where all the stray animals will go?
Here are some sad statistics from a 1997 survey of 1000 animal shelters by the American Humane Society:
> In 1997, roughly 64 percent of the total number of animals that entered shelters were euthanized — approximately 2.7 million animals in just these 1,000 shelters. These animals may have been euthanized due to overcrowding, but may also have been sick, aggressive, injured or suffering from something else.
> 56 percent of dogs and 71 percent of cats that enter animal shelters are euthanized. More cats are euthanized than dogs because they are more likely to enter a shelter without any owner identification.
> Only 15.8 percent of dogs and 2 percent of cats that enter animal shelters are reunited with their owners.
25 percent of dogs and 24 percent of cats that enter animal shelters are adopted.
And, as far as anecdata go, when my dog entered the shelter I adopted her from, she was pregnant with 12 puppies that were aborted. While I love puppies, I am glad they did that, for multiple reasons. Most important among them is that when we're destroying millions of animals a year, we don't need 12 more dogs in the shelter. But, secondarily, I am glad they did it, because if she had had the puppies, she would not be leaving that shelter for several weeks, which means I would have had a harder time adopting her. :)
A lot of shelters and rescue groups feel the same way. But, there are a lot of dogs who will get along just fine in an apartment.
One surprising example would be greyhounds. Yes, they are racing dogs, but, they generally are only interested in running for a couple minutes a day. The rest of the time, they're gentle couch potatoes, who make ideal apartment dogs.
A dog doesn't need a yard, it needs someone to tire it out every day. A neglected dog in a yard is not significantly happier than a neglected dog in an apartment.
Highly recommended. I don't go outside much, but I started pokemon go during covid-19, and it gives me a reason to head outside on a brisk walk to put a pokemon in a gym, or do a raid everyday. They doubled the distance you can reach gyms, so I can stand safely on the other side of the street from the gym and still be able to raid.
That's the gateway but the real problem is when you start to change habits, schedule and food preferences for maximum excersice effect. Now you are deep in the trench
I can't understand what kind of lifestyle doesn't allow for a 10 minutes walk. If you do housework for half an hour you probably exercise more than that.
It's not the allowance of time, it's the motivation (for me and probably 100s of millions of others??). I was walking 80 minutes a day prior to Covid lockdown, now I'm lucky to do that in a week. Principle change is motivation.
Start jogging, if your knees and back can take it, and try to keep the same total time (so longer distance). I fixed my distance at the start of my fitness improvement effort (5km) and walked it (40-45 minutes initially), then started running sections until they were longer, and eventually the whole distance. Got my time consistently down to 30 minutes, and for a brief period down to 23-24 minutes.
I agree that it is a good thing to publish results, even when they are underwhelming or unsurprising.
The main thing that DID surprise me in this study, was that the control group did so much exercise. The effect seen was likely small because it was compared to a control group that did nearly as much exercise as the MICT and HICT groups.
If they repeated this study in the U.S. instead of Norway, I think they would find a bigger effect.
There are many health problems that are mechanical failures. From fractured hip bones to plugged up arteries. Exercise is linked to building muscle and improving blood flow and lowering resting hear Rate. At this point the evidence is more overwhelming than smoking causing cancer. There is no good reason not to exercise. And the easiest exercise is just walking for an hour a day.
I recently watched a BBC Horizon documentary called "The truth about exercise" [1]. It argues that people do not respond the same way to exercise and that even 3 minutes of HIIT per week can make a significant difference.
It features a research by Dr. Jamie Timmons which he presents here[2].
> In line with this, observational studies suggest that exercise has a statistically significant preventive effect on premature all cause mortality with active individuals showing up to a 72% lower risk of premature mortality from all causes compared with inactive individuals
It's probably both. One big predictor of near-term all-cause mortality is the simple question, "can the person comfortably walk for a mile or two at a brisk pace?" (Barring existing mobility issues ofc)
Exercise helps to keep your body less stressed in many ways during its normal day-to-day life. It's good for your immune system, your circulatory system, your digestive system, and even your brain.
A few extra pounds probably won't cut your life short, but chronic heart disease or blood clots or being bedridden in old age definitely can.
Yes they mention in the paper mental and physical improvements.
In addition, the mental component continuous summary score was significantly higher in the HIIT group compared with control group (P=0.04) and MICT group (P=0.04) after five years (supplementary table S6).
Number one thing to get me out of a depressive funk, or help get unstuck on a problem? Get up out of my office chair and get some GD exercise! Even a simple meditative walk can do wonders.
I've heard it strenuously claimed from multiple sources that the most important exercises for the elderly are not strength-focused but balance focused.
There's a path from falling to bacterial pneumonia that, as one person put it, means that "The death certificate says the cause of death is pneumonia, but the real cause of death was falling."
I'm fuzzy on the degree to which HIIT would contribute to lower incidence of falling injuries. Meanwhile I have a large pool of anecdata about yoga and taichi, some of it first person (I have, in the last five years, tried very hard to break my own ankle on several occasions, but walked away without even a sprain).
What better way is there to improve balance than to get stronger? Isn't that what improving balance is: Strengthening the musculoskeletal system to support yourself?
This is why the focus on cardio related exercise for the elderly has always confused me. I'd like to see this study done with a basic strength training program instead.
No. Laying on a bench lifting weights does very little for proprioception, especially compared to exercises that have you shifting your weight continuously. It’s a bit hard to put into words, but as a concrete example, you try to step off a curb diagonally, and instead the inside edge of your shoe hits the top of the curb, twisting your ankle out from under you.
The correct reaction is to take all of the weight off that foot, otherwise once you hit the gutter you’re gonna have a bad time. A young person might solve this by hopping forward, to get your legs in front of your center of gravity. Another option is sinking down on the back leg while you draw the twisted ankle and your CG up and back until you can lift the leg and try to place it a second time.
Most of your time in the gym is either isolating a limb or putting symmetric loads on both. That teaches you nothing about not falling.
One failure mode for old people is having their “knee give out”. Having experienced this myself now, I think it has very little to do with strength and more to do with twitchy motor cortex (in my case, possibly due to a prescription medicine). Highly, highly unpleasant. That same weight shifting trick kept me physically safe if not entirely emotionally so.
The general recommendation for most people is to focus on compound functional movement lifts like squats, cleans, and deadlifts. Those absolutely help with balance. Knees and backs give out because they lack the necessary muscular support and stability.
Isolation exercises are mostly a waste of time unless you're targeting specific appearance or sports performance goals. The personal trainers at my gym have their clients lying on a bench less than 20% of session time.
I'd invite you to take a taichi class from a decent teacher and see if you still feel that way in a year. I definitely did not.
> Knees and backs give out because they lack the necessary muscular support and stability.
That is the common way, but not the only way. I was as surprised as anyone. I was literally in a taichi class the first time it happened, and I was nowhere near exhaustion. My knee just went on strike for a 10th of a second. Apparently I'm still mad about it.
There is something medically wrong with your body which probably doesn't generalize to me or most other people. While I'm sure Tai Chi brings certain benefits I prefer to spend my limited exercise time on other higher intensity activities. I can't do everything so I have to prioritize.
> There is something medically wrong with your body
Yeah, there's gonna be some things wrong with your body as you get older. Unless you die by misadventure, one of them will very probably get you killed.
'Injured older adult' is a club we all get invited to, and pharmacology so far seems to be a big exercise in replacing one set of symptoms with a less annoying set. Pharmacology adds all sorts of new dimensions to that (since we mostly play a game of symptom substitutions)
> Control participants chose to perform more of their physical activity as HIIT than the physical activity undertaken by participants in the MICT group.
The implications of allowing the control group to self-select their activities from the guidelines.
I wonder if they would have biased toward the HIIT activities (perceiving them to be better) simply because they were participating in the study. Would the outcome have been different if they were asked to maintain their existing activity levels or somehow replicate the normal activity mix of people following the guidance. Otherwise, it seems more useful to focus on the difference between the HIIT and MICT groups.
Serious questions for people who work on this kind of research or who have done so in the past:
Why do we need this kind of research? Don’t we already have enough to tell us that exercising is good, and that exercising more is probably better?
Ostensibly they were trying to compare the recommended levels of activity with high intensity and medium intensity exercise to see which was better, but would anything really change based on this research? Wouldn’t whatever resources that went toward this research be better put to use by getting more people to exercise instead of studying what’s “best” or whatever this is trying to do?
I understand that doing and publishing research is key to some academic careers (which is questionable in its own right), is that what’s really driving all this? For reference, my view on the role of research in tenured/academic jobs is probably pretty close to the negative viewpoint in this article that was posted on HN a while back:
Discussion [1] indicates that the control group were energised into exercising about as much as the "moderate" (not HIIT) intervention group. This is not an uncommon problem in intervention trials in this area.
Something is better than nothing. More is better than less.
This article's title doesn't really reflect the study. It should be like "5 year all-cause mortality with HIIT vs MICT training in healthy, active adults aged 70+".
For people who didn't read the abstract clearly: for old people, no noticeable differences in health benefits comparing HIIT to MICT to recommended physical activity.
Other studies show that exercise is better than no exercise for old people.
I was about to link a related news article I recently read, but realised it was the same study (done by my alma mater). One thing it also found was that they had a better quality of life, and those training together ended up being fond of the time spent together with new friends.
The 4x4 protocol btw is a staple in Norwegian training, at all levels. 4x4 and "fartlek" and you are soon an elite athlete is almost the mantra.
Wow what a disappointing result. Perhaps underpowered to detect what may only be a small change.
Also perhaps some selection bias in that the participants that sign up for an Exercise Study may already be pretty fit. And we see some of that in the baseline characteristics.
I don't think it was that disappointing. All it says it that the difference between elderly high-intensity and medium-intensity training is very little, and not statistically significant. Same with both combined compared to an elderly control group that is (I think) also physically active.
If you were to compare these groups to physically inactive groups I'm sure you would have seen quite a big difference.
I'm firmly in the camp that exercise is extremely beneficial. Likely one of the most beneficial things one can do (with not smoking and eating a diet high in fruits/veggies low in processed carbs).
We (society/physicians/etc) need tools to get people to exercise. This is more a study of how effective one of those tools might be (ie supervised exercise vs recommendations). If supervised exercise is no better than recommendations, I find that pretty disappointing. Because as we all know, recommendations don't work very well, or at least most people don't adhere to them.
>We (society/physicians/etc) need tools to get people to exercise.
One simple thing is making sure our infrastructure makes it safe to do so. Living in the south, I can't tell you how many side walks just end. How many roads have no crosswalks. Don't even get me started on bike infrastructure!
The car is king here, and I sincerely hope that ends some day.
Can someone explain to me what the title of this post means? The most literal way I can interpret it as is "Everyone that trained for five years died". I doubt that is what is really meant.
I remember it being said in a few places that exercise doesn't actually affect all cause mortality until about 10 years after beginning a regimen. So, I'm not surprised by the non-statistically significant result after 5 years, especially in such an aged population.
The swedish study discussed here is what I was remembering: https://www.health.harvard.edu/mens-health/never-too-late-ex...
They note that people who began exercising late in life didn't get much benefit to mortality risk by the 5 year benefit, but by the tenth year their risk was the same as the group that had always been active.
Edit: actually you need to google it to get to the un-paywalled article.
“Most importantly, men who were highly physically active at age 50 were 32% less likely to die during the study than those who were least active; moderately active men enjoyed a smaller, but still respectable, 13% lower death rate than the least active gents.”
“But the long-term nature of the Swedish study allowed the scientists to follow men who were sedentary at age 50 but who increased their exercise level between ages 50 and 60. For the first five years, the major result was disappointment, since these men continued to die at the same high rate as men who remained inactive. But over the next five years, the benefit kicked in; by 10 years of follow-up, the men who adopted exercise in middle age enjoyed the same low mortality rate as men who began before age 50. All in all, men who adopted exercise after 50 had a 49% lower death rate than the men who remained inactive, a benefit even greater than the 40% risk reduction experienced by men who quit smoking after age 50. And the protective effect of exercise remained significant even after the scientists adjusted their results for the impact of smoking, drinking, obesity, diabetes, cholesterol, blood pressure, and socioeconomic status.”
“According to the Swedish study, men were classified as moderate exercisers if they simply took frequent walks or often went cycling for pleasure. And high-level exercise involved a minimum of just three hours of serious gardening or recreational sports a week. And in case you're tempted to cook up another excuse, you'll soon see that this important study does not stand alone.”
The average age of participants in the study was over 70, so these findings apply only to the elderly. And the conclusion is not that “exercise is good”; the authors were actually trying to figure out if HIIT or moderate exercise was better. TLDR: HIIT is better
I've never been able to run a mile without stopping or under 10 minutes. I've had my heart cath'd and stress tested, nothing wrong there.
Would the intensity of HIIT and endurance of cross-country cardio be useful for significantly increasing aerobic capacity to get to running a mile continuously?
Cross training won't hurt and it's recommended for runners to reduce the risk of overuse injuries while building aerobic capacity. But if your goal is to improve at distance running then you're going to have to run.
Instead of grinding out a slow 11 minute mile try running at a 9 minute pace for a shorter distance. Then rest for a few minutes and repeat several times. Do that a few times per week and gradually increase the distance you run at the 9 minute per mile pace. Eventually you'll get to a full mile at your target pace.
Also if you're overweight you're going to struggle with running and be at higher risk of injury. If that's your situation then stick to lower impact sports until you drop the extra weight, then ramp up the running.
I was underweight and borderline anemic through early 20's and it didn't make a difference, but still huffed and puffed. I could do low intensity things like cycling for 10 hours a day, no problem, but jogging, swimming, or running would make my descending aorta vibrate my lower abdomen and maintain a typical hr around 120-140 bpm (resting bp was 100/50, now resting hr is 115 with bp 125/80). Trying to discontinue propranolol for endogenous? tachycardia with hypertension.
I'm in the process of losing 40 lbs (17%, cut) and then rebuilding muscle mass.
There is something wrong with your cardiovascular system. Have you been screened for an abdominal aortic aneurysm, patent foramen ovals, or arteriovenous fistula? A resting heart rate of 115 is crazy high. Get a second opinion from another cardiologist. Ask for imaging studies, treadmill stress test, and a Holter monitor. Good luck.
- The RCT was done only on individuals aged 70-77
- Furthermore the results were not statistically significant at p < 0.05. You can see this in the visual abstract where the 95% CI overlaps with risk ratio = 1.0, where 1.0 means "no difference" between the groups.
Note that the results being non-stat sig does not mean that there was no difference! It means that the difference, if present, was probably too small to detect given the power (number of participants) included in the study. This is important to understand!
Furthermore, in the "Strengths and limitations of this study" they clearly outline some reasons why the results may have been non stat-sig, including:
- "Firstly, participants in the control group had a high level of activity throughout the study, and many exercised using HIIT. This might have affected the study’s ability to detect statistically significant differences between groups."
- "selection bias might have influenced our results, as participants were more active and had better overall health than non-included participants"
Basically, even the "control" group looked like they had a good baseline level of activity, decreasing the activity level difference between that and the two treatment groups.
My takeaway from this study is that in isolation, it doesn't provide much evidence for or against the effect of exercise, but taken together with other studies can be used for evidential value.
The results can also be used to inform future studies. The authors clearly understood this when they stated in the main measure outcome: "An exploratory hypothesis was that HIIT lowers mortality more than MICT."