Re: What do YOU do?
I prep pre-season by doing some weight lifting in an effort to ward off the "first run soreness" issues. I have a pretty nice weight machine at home and focus on trying to use that especially during winter. This tends to bore me, so when I find myself slacking off, I make a definite effort to drop down and at LEAST do several sets of crunches & pushups during TV commercials when I'm just sitting around feeling like too much of a slug. I always lose some conditioning over winter. I'm also a very aggressive backcountry snowmobiler, which means my snowmobile gets stuck a LOT. Weighing 650 pounds, digging a sled out of 10 feet of heavy snow can be a serious 1/2 hour workout, especially if I'm riding at 10,000+ ft of altitude. Sadly, this doesn't happen nearly as often as I'd like it to simply because of cost and distance from my home...but it does count as significant exercise when I get the chance. And such planned trips usually motivate me to get back on weight lifting and some cardio workouts in the weeks leading up to an aggressive snowmobile trip.
I usually get out to water-ski at least 2x per week all summer. Mostly slalom, which is incredible full body exercise...kind of like doing interval sprints. When ski season starts, I do less weight lifting, but I start skiing and bike riding. I ride my bike about 2,000 miles per year, but only in decent weather...so that takes care of my cardio from about early April thru early November.
I find the best exercise that I can consistently maintain is the exercise that actually gets me DOING something or going somewhere. Water skiing, bike riding, hiking, snowmobiling, or good old fashioned manual labor like chopping wood, roofing houses, digging sod, shoveling snow, helping friends move into to new homes, etc. I seek out these types of events and projects whenever I can, and I always try to break a good sweat when doing them...often favoring and reaching for hand tools (an antique handsaw) instead of a power tool (expensive new chainsaw) because I WANT the project to take longer and be more difficult. Drives lazy people nuts, but it's good for me! I do work projects at church and Lions Club, volunteer for Habitat for Humanity, etc. And I'm ALWAYS the one who volunteers for the sweaty, physical, hard jobs that nobody else likes to do...that's some of the best and most enjoyable exercise I get.
Enough on my philosophy. Enjoy your studies and your project!