There's a certain sort of cocky first year, which both my boyfriend and I were (are? when am I considered a second year?) that starts off thinking that you can work in lab sustainably 7 days a week. As an undergrad, I essentially did that--7 days a week I was either studying or in lab, pretty much constantly working except Friday and Saturday night.
Well there are numerous, copious differences between graduate school and undergrad, most of which won't be touched upon here (like the difference between it being your job to produce results and having research be strictly pedagogical, which is a big one). But one large thing that I didn't factor in was the existence of long winter breaks and summer breaks. Summers I was working in labs, but I always took at least a couple weeks off on either end of the summer, and I generally was working a 9-6, five days a week schedule because I needed someone to supervise me who didn't want to be around on the weekends and evenings. Winter break was a good 5 weeks long, and the only winter I spent most of it working was my senior year (and even then I took a good 2 weeks off around Christmas). So you can sustainably work full throttle, because you are really only doing it for 4 month chunks.
Well in graduate school, I get 2 weeks off for vacation. There are times when I need to work full throttle...when things are going well, or last semester during midterms/finals when stuff started to pile up. There are times when your personal life goes to shit and you immerse yourself in work to escape how shitty your life has become. But there aren't these long recuperative breaks. It's no longer this 4 month sprint, dictated by the semesters (as much...there's still a bit of that); it's continual. You need to work sustainably.
So the older students are right, generally if you take one day off a week to spend doing something not lab-related, you are more productive and happier and more able to work all out during the normal work-week. And it's not because they lack the same enthusiasm for what they do, but just that they know what is sustainable and what is not. And we are not special. Everyone starts out that way. It's just the way things go.
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