I split my findings into categories and bolded the parts of the studies I found most interesting. I really didn't take the time to be super critical on study design, etc; I was just taking their findings at face value and seeing what, if the study was true as reported, was being claimed. Enjoy!
1. Sleep
2. Cognitive Function
3. Fatigue
4. Stuff I didn’t understand but maybe someone else does
Takeaways:
One final comment - while I couldn't really make a strong case for resistance training being obviously better than aerobic training with respect to productivity in any manner, I still think that 1) resistance training probably does have absolute benefits to cognition and energy levels, and 2) there are many reasons to pursue resistance training outside of productivity (for instance, things like osteoporosis risk didn't come up in a productivity-related search, but would be relevant when I design my own workout plan).
I've decided to curate this answer. (This is a bit of a nonstandard use of LW Curation. Hopefully some day we'll have a better process for curating answers)
I have similar thoughts on this answer as I do on a previous curation notice for another literature review. I want LessWrong to be a place that incentives many kinds of intellectual work. Eventually, some day, I want LessWrong to be a place you can come to get the best answer given the current evidence on scientific questions, even if the data is murky.
There are a lot of pieces of that. Lit reviews are one of those pieces, and I don't think they're sufficiently incentivized by the default crowdsourced karma system.
I appreciated that this post outlined a number of concrete facts about what hereisonehand was able to find out. I also appreciated them writing up their process afterwards, so I have a sense of how reliable and representative the information is.
An area this answer could have been improved in was better distillation/presentation. (Something I considered before curating it was asking the author to optimize it a bit for readability. I ended up not doing that for slightly complex reasons but might do so...
I think this answer was good, but also feel like curating it (and skipping the team-discussion that usually goes with curation) was a mistake. This answer really needed, at a minimum, a formatting cleanup, before it was ready for curation. I tried to read it, and I just... can't. Too many fonts, too much inconsistent indentation. And I would've appreciated a chance to make the curation email work right (ie, make it include the actual answer), before this went out.
Thanks for writing this! It was useful when organising my workout routine.
I read the Kovacevic et al paper on sleep you cite, and there are some caveats probably relevant to some LW readers. In particular, the benefits are less clear for younger adults.
This comment wins. This is beyond what I was hoping I would get and I'm really glad I asked. Thanks hereisonehand! Message me with paypayl/venmo/etc info to claim your prize.
"high intensity aerobic exercise provides the benefit, and resistance training, if it includes high intensity aerobic exercise, can capture that benefit."
Which part made you conclude that high intensity aerobic exercise is needed? Asking because most resistance training doesn't include it.
Great answer, thanks!
Hey! Great question. The conclusion regarding aerobic exercise came from lots of the literature I was reading saying something like "the effect went away when compared to aerobic exercise." I should probably not have said "high intensity," as I don't really remember looking specifically at any intensities, but umm - below I'll list the evidence from my answer that kind of points this out. [all of this is just pulled from my big answer comment so if you want more context, look there for the link, etc]
Having looked at it again to list the evidence, I think the evidence I saw was basically.
A. Comparison: resistance to aerobic = no difference
B. Comparison: aerobic to resistance+aerobic = no difference
So I concluded that
The effect of resistance and aerobic on sleep and cognition don't seem to be independent (or rather, at the very least they are not additive - comparison B).
I guess my thought was that if resistance = aerobic = resistance + aerobic, then either you're getting the benefits of resistance training from aerobic exercise or you're getting the benefits of aerobic exercise from resistance training. The latter just seemed more plaus...
This isn't delving deeper into the studies raised in the comment, I just wanted to emphasize the virtuous-cycle nature of a couple of these things. I got most of this from Stronger By Science, but I'll include the links to the papers directly, and the post analyzing them secondly.
Related: Meditations on Momentum
First, sleep. The study linked in the answer claims resistance training improves subjective sleep quality, but the relationship works the other way as well:
Insufficient sleep undermines dietary efforts to reduce adiposity
This study found t...
Really nice job. I think I'm persuaded by your conclusions, and I intend to try to mix in more aerobic exercise. How did you do the search?
Thanks! To be honest I wasn't nearly as systematic as I would've liked. I did keyword searches on Google Scholar and PubMed for resistance training and weight training. On PubMed, I specifically looked for review articles and meta-analysis in one search just to look for big picture studies, but as you can see, results were a bit sparse so I also just searched generally for any articles I could find.
I'm trying to get better at this process (ask a question, research the answer), and I'm in the early phases. Future goals include 1) having a more systematic search process to avoid bias (i guess in theory the results above could be heavily biased if I just didn't know to use certain search terms), 2) getting into the nitty gritty and actually critiquing studies and meta-analysis themselves (I just trusted blindly here, which is fine for now but it would be cool to get better at parsing methods)
There is some indirect evidence that weightlifting improves productivity, assuming that cognition is an important determinate of productivity.
For example, a recent meta-study, Lifting cognition: a meta-analysis of effects of resistance exercise on cognition by Jon-Frederick Landrigan, Tyler Bell, Michael Crowe, Olivio J. Clay, Daniel Mirman, reports that:
Results revealed positive effects of resistance training on composite cognitive scores (SMD 0.71, 95% CI 0.30-1.12), screening measures of cognitive impairment (SMD 1.28, 95% CI 0.39-2.18), and executive functions (SMD 0.39, 95% CI 0.04-0.74), but no effect on measures of working memory (SMD 0.151, 95% CI - 0.21 to 0.51).
That much closer to what I was hoping to find than I found initially, and I'd say it passes the initial bar. A few knocks against it are the focus on the elderly (the mediate age was 70) and the high variability in the outcomes. I'm not familiar enough to know what to expect, but those plots look all over the place to me.
List of papers
Some incremental progress, just taking the obvious first action of "search google scholar for 'benefits of exercise on productivity'", followed by a search for "benefits of strength training on productivity" after remembering that the first one wasn't quite right (but maybe still useful enough to include)
Including random quotes that seemed most relevant (did not search anything very hard)
Does strength training programme improve work task performance in young adults with Down Syndrome?
https://bmcpediatr.biomedcentral.com/articles/10.1186/1471-2431-10-17
The effect of the PRT programme on work task performance will be assessed using two tests (a) repetitive weighted box stacking and (b) weight carry test (pail carry). The repetitive weighted box stacking test requires the participants to repetitively lift 10 kg boxes, from the floor to a table 75 cm off the ground. The number of boxes stacked in one minute is measured. The weighted pail carry requires participants to carry two 20 litre buckets each weighing 10 kg around an oblong 10 m course marked with cones. The total distance covered in 30 seconds is measured in metres. Running is not permitted for safety reasons. These measures are recommended by the American College of Sports Medicine [33] and have demonstrated changes in people with intellectual disability [34, 35].
The impact of a self-paced exercise program on productivity and health outcomes of 32 adult workers in a large federal office complex was investigated during 3 months.
https://journals.sagepub.com/doi/pdf/10.1177/216507990705500302
Walking was the sole form of exercise. The first month, during which no walking occurred, was the control period. The second and third months were the experimental period. Participants were divided into three levels based on initial weight and self-determined walking distance goals. Productivity (using the Endicott Work Productivity Scale), walking distance (using a pedometer), and health outcomes (blood pressure, weight, pulse rate, and body fat percentage) were measured weekly. Results from this study, based on a paired t test analysis, suggest that although the self-paced exercise program had no impact on productivity, it lowered blood pressure and promoted weight loss. Further study using a larger sample and a controlled experimental design is recommended to provide conclusive evidence.
Exercise is more than medicine: The working age population's well-being and productivity
https://www.sciencedirect.com/science/article/pii/S2095254616300096
In Denmark 15 randomized controlled trials have been conducted, introducing exercise at the workplace enrolling >3500 workers. The interventions lasted from 10 to 52 weeks and offered ~1 h weekly supervised exercise during working hoursaccording to the concept of intelligent physical exercise training (IPET) that is based on evidenced sports sciences training principles and tailored to work exposure, employee health status, and physical capacity. Questionnaire surveys and health checks including blood and muscle sampling were performed at baseline and follow-up. The job groups included: office and computer workers, dentists, industrial technicians, cleaning personnel, health care workers, construction workers, and fighter/helicopter pilots.
[...]
Poor health among employees implies substantial costs for the companies. The costs relate to increased sickness presenteeism (decreased on-the-job-performance while being at the workplace) as well as absenteeism (habitual absence from work) leading to loss of work productivity.37 Sickness presenteeism was assessed as self-reported on-the-job-performance, using questions in regard to productivity, work ability, and quantity and quality of work.
Importantly, in spite of spending 1 h a week performing physical exercise training during work time, in none of our studies we found a decrease in the variables underlying on-the-job-performance.
However, we did, in an intention-to-treat analysis, find a significant 8% increase in productivity of the intervention among health care workers after 3 months but not after 1 year of intervention.38 Likewise among dentists we found improved self-reported quality of work.18
Interestingly, some exploratory analysis of our RCTs actually revealed some relevant findings: productivity increased with decreased neck/shoulder pain, and with improved muscle strength—in particular trunkflexion and extension—as well as decreased BMI among health care workers.37Further, workers with sedentary monotonous tasks (office/computer) —who were physically active at leisure compared with those being inactive—perceived less stress and more energy. These perceived differences were underlined by corresponding differences in physiological measures of the stress-hormonecortisol.39 Regarding sickness absenteeism analysis on our RCTs so far has not identified significant changes with the interventions.
The Benefits of Exercise for the Clinically Depressed
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC474733/
While most studies have employed walking or jogging programs of varying lengths, the efficacy of nonaerobic exercise has also been assessed. For example, in comparison with a control condition, resistance-training programs reduced symptoms of depression (resistance training vs. control resulted in BDI reduction of 11.5 vs. 4.6, respectively, p < .01, and HAM-D reduction of 7.0 vs. 2.5, respectively, p < .01).21
Aerobic and nonaerobic modes of exercise have also been compared to determine if certain types of activities are more effective than others. Doyne and colleagues22 compared the efficacy of running with that of weight lifting. Forty depressed women served as participants and were randomly assigned to running, weight lifting, or a wait-list control group. Participants were asked to complete 4 training sessions each week for the 8 weeks of the program. Depression was assessed at mid- and post-treatment and at 1, 7, and 12 months follow-up. Results indicated that the 2 activities were not significantly different, and that both types of exercise were sufficient to reduce symptoms of depression (running vs. weights vs. control resulted in BDI reduction of 11.1 vs. 13.6 vs. 0.8, respectively, p < .01, and HAM-D reduction of 6.7 vs. 8.7 vs. a 1.0 increase, respectively, p < .01).
Further, there were no differences between the 2 treatment groups during follow-up with respect to the percentage of participants who remained nondepressed. Similarly, a study by Martinsen et al.23 assessed 90 depressed in-patients who were randomly assigned to aerobic or non-aerobic exercise. Aerobic exercise consisted of jogging or brisk walking, and nonaerobic exercise included strength training, relaxation, coordination, and flexibility training. The program was 8 weeks in length, and participants exercised for 60 minutes, 3 times per week. Those in the aerobic group exhibited an increase in PWC compared with those in the nonaerobic group. However, both groups experienced a significant reduction in depression score (p < .001), but there were no significant differences between the groups with respect to the magnitude of change in depression score (p > .10).
To do, by either me or someone else: look into some of these in more detail and think about the quality of the evidence and how it bears on JP's question.
Maybe a good practice is, if you are interested in doing that for one of these papers, reply here with your intent to do so (so you don't overlap with someone else) and then add a new Answer with your additional thoughts after spending 15-30 minutes on it
Extremely strong.
... I'll see myself out.
My personal experience: exercising makes me feel better. One can't do much when he feels bad, right? Hence I believe that exercising makes one more productive. It helps me to cope with depression, too. I might feel very terrible sometimes, and in such moments exercising is what helps me to get back on track. Without exercising one will rot, I think. Exercising is good, in moderate measures.
Is there a deadline? I'm a bit busy until the end of this week, but I wanted to try my hand at doing some lit review soon anyways. I'll probably take a shot at this sometime next monday.
I suspect doing long-term (or any) studies on people diagnosed with depression and weightlifting would be difficult, since the motivation required to do regular heavy exercise is either preventing people from following a strict routine or it would disqualify them from the clinical diagnosis of depression. I have tried exercise as part of my life-long battle against depression and in a recent conversation with a therapist was told that I am in fact not depressed, because a depressed person "is not be motivated to invest effort into doing something about their depression".
[Mod Note: This question received an answer that seemed worth curating. See the answer by LW user hereisonehand for the curation notice]
I've been weightlifting for a while, and I've heard vaguely good things about it's effect on productivity, like a general increase in energy levels. A recent quick google search session came up empty. If someone looks into the literature and finds something interesting I'll pay a $50 prize.*
Assume the time horizon is <5 years. I'd prefer answers focus predominantly on productivity benefits. Effects on cardiovascular could be part of an analysis, but would not qualify on their own. If the evidence is for something clearly linked to productivity, like sleep, I'd count that. Introspective evidence will also not qualify. Comparisons to other forms of exercise would be especially interesting. Assume a healthy individual, although I'm at least somewhat interested in effects on individuals with depression or anxiety given their prevalence.
*Prize to go to best answer, as judged by me, if there are any that meet some minimal threshold of rigor, also as judged by me.