Back in the day my then boss once was bitten by the Wheel of Energy bug. Simply put, your total energy can be described as a circle which is divided into three segments: Work, leisure/hobbies and rest. For optimal energy the three should be balanced. If one segment is bigger than the other two, the weight of it will stop the wheel from spinning.
Dehydration is another issue. A hot environment, thick/dark clothes (sunshine on a breezy day in spring), efficient ventilation (aeroplanes) all can dry yourself without you noticing. Caffeine is a diuretic so coffee or coke can make things worse. Some common vegetables like watermelons and tomatoes also remove fluids from your system - handy if you have swollen ankles but not so much if you're already dry as a raisin. Excessive drinking of plain water (a gallon a day) can also be an issue as it can change your salt balance. Even more so if you sweat a lot.
I don't usually work a lot of hours. Pretty much an 8-hour day. And I have a pretty sweet job. I actually love the job. I'm pretty much on my own out in the field. Today I'm in the office. Just some of the environments can be hard but not all of them are.
I drink a lot of water. So much so that I think I sometimes drink too much water. And I don't drink sodas or anything like that. I have healthy snacks with me during the day like I'll have a banana and some peanuts or something like that.
My work life balance does seem skewed though because I think I just don't have energy when I get home to do anything. Like I will get up at 5:00 a.m. and usually make breakfast and get ready for work. I'll be at work by 8:00 and then I'll work and come home usually by 6:00 p.m. . And then when I get home and I finally get a chance to sit down or whatever, I feel like I'm just zonked out at that point. Like I don't have the energy to do the things that I thought I was going to do during the day. Like I will plan to make time for a guitar part or something like that and then I just can't do it when it comes time to getting home. I'm just exhausted.
So I'll go to bed and I'll read a little bit while I'm in bed or maybe look at the internet a little bit. And then I'm zonked out. Only to wake up the next day to do it all the same again.