I am doing postdoc in developmental biology. Recently I started to leave work at the lab, meaning that I don't work at home anymore. Before I spent many hours at night (at home) analyzing my data; now I spent that time on my side project not related to science.
I would like to ask if that kind of schedule is sustainable? Can I be a good scientist if I only work in working hours (now and later when I have a long term position)? Other scientists seem to work both at the lab and at home.
It is possible. For the last eleven years (from the seventh month of my PhD trajectory onwards) I have worked the standard 40-hour work week: Monday through Friday, from nine to five. I don't work weekends, and I don't work evenings. Last Summer I got tenure.
Even though it is possible, it is not necessarily easy. You will need to be very efficient within those 40 hours a week, and you will need to have the support of those around you. If your university has the culture that faculty are available for work at all times, it's going to be hard to break through that culture on your own. Even if your university supports you in fighting for a reasonable work/life balance, you still may need to manage the expectations of those around you; I have made my colleagues aware that they shouldn't expect, for instance, email replies from my side on the weekends.
It is also entirely possible that in the long run, my 40-hour policy will reduce my chances for promotion: if full professorships open up, I may lose against those people that have worked 80-hour weeks. I'm not convinced that this will necessarily be the case: by regularly taking time to relax, I ensure that my mind is very sharp during the working week, and that makes me more productive in those 40 hours than others can be in 50, 60, or even more. But even if my policy will cost me an eventual promotion to full professor, I will not regret my choices: by working 40-hour working weeks, I get to spend lots of time with my family, which is simply more important to me.
How well this will work for your career depends entirely on your ambitions.
If you want to become a professor, it will likely be very difficult to limit your work to a normal work-week. Competition for faculty positions is extremely high and many of your competitors will be working well beyond normal work-hours to make themselves as attractive as possible for potential faculty hiring committees. There is also a very "macho" culture in much of academia that supports this type of burnout-inducing overwork.
If you are OK with working in research outside of "traditional" academia, however, it's quite possible. In addition to industry (which spans a very broad range of research maturity levels!), there are all sorts of non-profits, national laboratories, foundations, consultancies, government agencies, etc. Some of them have the same problems as academia (especially startups), but many of them have much more humane cultures and are much more serious about work-life balance
Bottom line: mostly no, for "traditional" academia, yes for the much larger research world outside of it.
If you wish to stay in academic research, what is important is that you produce thoughtful, rigorous and impactful work, that gets published well, and well cited. How you arrange your life to achieve that is a personal question and no one else can dictate to you what the best way for you is (no matter what some colleagues might try to tell you).
It is true that most people in academia do work significantly longer than the standard hours. There is a macho culture that says you have to do this, and people compete to have the most outrageous schedules. But this is not universal. I know some very talented and successful professors who have always only worked (more or less) office hours. Perhaps 8-6 rather than 9-5, but still, not the crazy hours you hear about. Often those with children have no choice. What these people have in common is a razor-like focus on what is important, and a very well developed organizational ability. By co-incidence a fair number of these are developmental biologists.
Not everyone can achieve this, but its not impossible. I know I can't, its just not how I work. I do tend to only work at the lab, its just often I spend long hours there. And even I manage to maintain side projects beyond academia despite being an early career PI (not sure I could if I had children).
I think one source of the trope that as an academic you have to work insane hours is simply a question of perception. Academics often mix private and work life a lot more than people in other professions. Because they can. And because it fits the type of work. Like a colleague once said, "I don't care about your office working hours, as an academic you also work in the shower when the right inspiration hits. I care about your output.". I always loved the possibility to just take a 2h break in the middle of the day to hit the pool at sunny days and then work a bit more in the evening - or half an hour in the whirl pool. But that means that many academics also work sometimes at least on the weekend, because that is when they get an idea or because a deadline is close and they work well with deadline motivation or because right then an experiment needs attention etc. So while there are 70hours work people, a good percentage is likely perception.
So from my perspective, in many academic jobs you may need to be more flexible compared to regular 9-5 jobs. I.e. you may need to be fine with deadline crunches, video chats at insane hours with collaborators from the other side of the world, checking your experiments on the weekend etc. Then again, it's a field where you also can be more flexible and just run off in the middle of the day to run some errands. Academia like, say, game development, attracts a lot of enthusiasts who love their work, but in both branches for most people a healthy life-work balance is important to stay productive. However, 9-5 jobs aren't necessarily providing a healthy life-work balance. The ideal mix can be real individual. However in academics you might find that flexibility often counts more than the overall hours. Work on hard problems when your brain is willing and eager, no matter the time, but also give yourself times to relax in sufficient ways.
That being said, there are also jobs in academia that fit well with a 9-5 job, but they are more rare than if you decide to be - say for example - a car mechanic.
You will in any job compete with over-achievers. With people who put in insane amounts of time (whether that actually helps them to get better results or not) and with people who seem to have not to work at all and still get better results. Don't measure yourself by other people. Measure yourself by your own achievements, how happy you are with your job and with what you earn to support yourself/your family.
My friend is an astronomer who has discovered several exoplanets, and is quite respected in the field. He certainly does not work more than the standard working hours sum up to, but sometimes crunches two weeks worth of work in one.
Working in the medical field myself, we have different realities. Some doctors do respected research, but maybe suitable patients for their topic come about twice a month. They collect data for years along the work, and then put together a paper, not necessarily sweating too much.
I guess it depends entirely on what you do. Obviously one can be a legendary mathematician with very little amount of hours, as long as you come up with the stuff.
My impression is that biology (the lab intensive microbiology especially) does require a solid amount of hours to get anywhere. Though I'd suggest to be aware that in many cultures it is customary to magnify one's hard working spirit and "productivity". Americans do this a lot, and often overestimate and exaggerate the amount of work people they somehow admire do, even if they have absolutely no clue about the field, or the actual job.
Limiting yourself to only work at fixed times will on the long run not work out well. If you work from 9 to 5 every day, you'll tend to plan your work more tightly than if you allow yourself more flexibility. The constraint on work time in combinations with deadlines that you have to meet, will end up steering your work routine toward a "getting things done" mode, where "getting things done" is visible progress after one working day, like progress made writing an article, finish work on a conference talk etc.
You'll then end up performing quite well on getting routine tasks finished on time and also performing quite well on such tasks. However, you'll end up falling short on obtaining spectacular new results. The main difference between ordinary work for industry and science is that you need to also explore ideas that in your judgment are unlikely to yield good results.
If you always bin ideas that according to your preliminary analysis, are unlikely to work well, you'll end up working on things that will end up yielding results but not really spectacular new results. The reason is that anything that's easily visible as potential spectacular result has likely already been investigated, so the new spectacular results are usually hiding as things that look like bad ideas not worthy of investigating.
It's then your 9 to 5 work routine that biases you to not go all out on far-out ideas. If it's Friday and you look at your watch an you see that it is 3 pm and you can work for two hours to finish writing part of an article and also work on your conference talk for next week, you are unlikely to opt for spending the next two hours on, say, writing software needed to investigate some far-out idea. Your colleague who does not mind working in the weekend could more easily make that choice, as he/she can decide to do work on the article and the conference talk in the weekend.
In academia, you will be evaluated on your accomplishments, not how long you worked on any given week. While it's not a perfect analogy, you might consider yourself a salaried employee -- you are not paid hourly, you are not offered overtime. You put in enough hours to accomplish what your salary is paying you to do.
My experience is that there will be time periods where you need to work very long hours, and time periods where you will not need to work long hours. If you're a better time manager than I am, which is likely, you will probably need to work less hours than I do.
If it's very important, for example, to get a grant in before deadline, and you find yourself in a position where you need to put in 70 or 80 hours a week for three weeks to get it done, you do it, or accept the consequences for not doing it. If you're not amenable to that schedule, than you fix your time commitments in the months leading up to that so you don't have to be in that situation, and can still reach your goal in a 40-hour week.
All that said, you're seeking a career of responsibility. You will have people working for you, and people dependent on things getting done. If people find you're not getting things done, "I only work 40 hours a week" will not be something people will want to hear.
