It's hard to know what to do when the math requires more hours in the day (and dollars in the budget, etc.) I can tell you that my body really went to hell when I cut back on exercise, in favor of more work hours. It's not something that one can keep up forever. And going without sleep starts taking a toll before long also. A couple of times, we have shut down big projects because everybody just needed to get some rest. Too many expensive mistakes were being made.
I have known a few people who can get by with several quick naps throughout the day, instead of a night's sleep. I sure can't do it.
There isn't an easy solution, but this is one of the reasons that I dropped gym membership and started building up a home gym. I needed the time that I was spending to travel to the gym. In some cases, running or bicycling to work, instead of riding a bus or driving, can add exercise time without really adding much travel time. Sometimes it's possible to work in some light exercise with study, such as spinning while reading, or reading between sets. (Actually, sometimes this helps because I think about what I just read while I'm lifting.)