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.
First, sleep. The study linked in the answer claims resistance training improves subjective sleep quality, but the relationship works the other way as well:
This study found two groups on the same diet while sedentary lost the same amount of weight, but for the group on 5.5 hrs of sleep 50% of that weight loss was muscle, whereas for a group on 8.5 hrs of sleep only 20% was. This has significant implications for trying to increase or even maintain strength. More commentary here.
This review found that lack of sleep interferes with hormone balance, namely by doing things like increasing cortisol and decreasing testosterone and growth hormone. More commentary here.
In a nutshell, resistance exercise improves sleep improves resistance exercise, and so on.
Second, comparison with aerobic exercise. A couple of the studies above compared aerobic exercise with anaerobic exercise, and found the effect of one or the other was stronger (on cognitive function, for example).
As it happens, these two are also mutually reinforcing:
concludes that resistance training improves cardiovascular fitness; improved cardiovascular fitness results in better recovery and the ability to sustain higher resistance training loads. This effect is mitigated by specific exercises, though:
found that running interferes with strength gains, but cycling doesn’t, for example. More commentary on these points here.
In a second nutshell, strength improves cardio improves strength, and so on.
So while there is independent evidence of resistance training, and aerobic training, and sleep all providing benefits relevant to productivity, they also form a mutually reinforcing system where each seems to help the other two directly.
I don’t have any information on how these things scale; for example it feels ridiculous to think twice as much resistance training leads to twice as good sleep. I also don’t have any indication of how much substitution there might be—for example, is the sleep benefit just because you are active at all? Is there difference between 5/week of weights vs. 5/week of cycling vs. 5/week alternating? What about if they were 30 minute workouts vs. 60 minute workouts?
That being said my gut feeling is that a combined system would be much more resilient in its benefits. Anecdotally, weights 3x a week and HIIT or yoga or something for the other 4x a week has yielded improved sleep, more stable energy throughout the day, and ~40lbs weight loss in tandem with calorie control over 7 months. This has considerably improved my productivity; I gained a couple of hours of useful time outside of work, and all the hours are higher quality now.
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 two groups on the same diet while sedentary lost the same amount of weight, but for the group on 5.5 hrs of sleep 50% of that weight loss was muscle, whereas for a group on 8.5 hrs of sleep only 20% was. This has significant implications for trying to increase or even maintain strength. More commentary here.
Sleep and muscle recovery: endocrinological and molecular basis for a new and promising hypothesis.
This review found that lack of sleep interferes with hormone balance, namely by doing things like increasing cortisol and decreasing testosterone and growth hormone. More commentary here.
In a nutshell, resistance exercise improves sleep improves resistance exercise, and so on.
Second, comparison with aerobic exercise. A couple of the studies above compared aerobic exercise with anaerobic exercise, and found the effect of one or the other was stronger (on cognitive function, for example).
As it happens, these two are also mutually reinforcing:
Resistance Training to Momentary Muscular Failure Improves Cardiovascular Fitness in Humans: A Review of Acute Physiological Responses and Chronic Physiological Adaptations
concludes that resistance training improves cardiovascular fitness; improved cardiovascular fitness results in better recovery and the ability to sustain higher resistance training loads. This effect is mitigated by specific exercises, though:
Concurrent training: a meta-analysis examining interference of aerobic and resistance exercises.
found that running interferes with strength gains, but cycling doesn’t, for example. More commentary on these points here.
In a second nutshell, strength improves cardio improves strength, and so on.
So while there is independent evidence of resistance training, and aerobic training, and sleep all providing benefits relevant to productivity, they also form a mutually reinforcing system where each seems to help the other two directly.
I don’t have any information on how these things scale; for example it feels ridiculous to think twice as much resistance training leads to twice as good sleep. I also don’t have any indication of how much substitution there might be—for example, is the sleep benefit just because you are active at all? Is there difference between 5/week of weights vs. 5/week of cycling vs. 5/week alternating? What about if they were 30 minute workouts vs. 60 minute workouts?
That being said my gut feeling is that a combined system would be much more resilient in its benefits. Anecdotally, weights 3x a week and HIIT or yoga or something for the other 4x a week has yielded improved sleep, more stable energy throughout the day, and ~40lbs weight loss in tandem with calorie control over 7 months. This has considerably improved my productivity; I gained a couple of hours of useful time outside of work, and all the hours are higher quality now.