Archived from my FB page from Dec 18, 2016
Since Charynn McCurdy specifically mentioned she has no kitchen in her quarters, I thought I'd do this one a lot earlier than I would have otherwise.
Everyone fixates on what the pros do. No one stops to consider the differences between themselves and the physical demands pro athletes routinely live their lives with.
In an effort to keep it honest and the pain at a minimum, you ain't that. To be honest, the specialized diets that professional (or even "only" high level amateur) athletes require would be almost entirely wasted on someone just beginning their athletic journey. The actual food consumed would be healthy, but it wouldn't be in the proportions your body needs, so you wouldn't achieve the results top level athletes would from such a refined diet plan.
What anyone needs to focus on in the beginning is discovering their physical limits and refining their existing body from that of a sedentary human into an athletic human (and not all that athletic, when you get right down to it). That means learning how to perform the most basic physical activities, and healthy calorie restriction.
If you can reduce your food and beverage consumption of calories to a daily average of 1600 calories, you will lose body fat. If you can perform a daily exercise routine (particularly one that varies from day to day to include all of the major body parts as well as aerobic activities like brisk walking or slow running) along with that, you will gain muscle tone and some muscle mass. Only after you have achieved the basic muscle-to-fat ratio and physical strength-to-weight ratio your body is naturally capable of are you ready to begin building beyond your natural body parameters of muscle mass or perform any of the more extreme physical activities.
How to get started? Go to the store (or the commissary, if the .nav still has such a thing). Start reading the data printed on the packaging of the food items you can keep and prepare in your quarters. The only really vital data point you should be noting down for now is the total calories per serving amount. While you're there, buy a jumbo bottle of a daily vitamin (one with an iron supplement included would be useful since you're a woman) and a bottle of vitamin D supplement (I recommend the 5,000 IU dosage). This will provide you with the basic vitamins necessary to good health, even if your diet were to be much more restricted than what is proposed here. Do drink enough clear liquids to keep your urine clear-ish, mostly not-too-odorous, and of reasonable quantity to keep your kidneys working.
Anyone can make a sandwich if they have a refrigerator to keep the makings in. How many calories in a couple slices of bread? How many calories in a tablespoon of mayo (or mustard or ketchup; insert the condiment of your choice here)? How many calories in a slice of your preferred sandwich meat (don't forget to include things like tuna here)? How many calories in a package of shredded lettuce or a tomato? When you reach a total of 400 calories, all you have to do now is put it all together into some form you can get down your neck instead of your shirt front. :)
Look around the store for the powdered drinks. Buy one each of every flavor of Crystal Light you think you might like and at least two 1 quart tupperware drink containers. If you have to have fizzy drinks, buy a bottle or two of carbonated soda water. For regular drinking, mix the Crystal Light as directed and drink as much as you want. If you are completely fiending for a fizzy drink, mix a package of Crystal Light with about 40% of the usual water required, stir like crazy until it's reasonably well mixed, fill a glass about 60% full of carbonated water, top up with the concentrated Crystal Light mix and belch with gusto. If you let both containers get cold first, you can do it without ice even. Oh, and Crystal Light flavored ice cubes are an excellent way to make a glass of tap water seem a whole lot more palatable too.
When you absolutely cannot face another sandwich, total up the calories from a salad instead (just go with a vinegar-and-oil dressing and look around for small packages of different kinds of nuts for variety. Other than peanuts, most nuts are surprisingly high protein for their caloric content). Again, 1600 calories total per day.
Total calories in a packet of ramen noodles? 190. Get about 200 calories of diced meat from the deli, add a splash of soy sauce (go on, splurge, make it two splashes), cover the lot with water from the tap and you're about 2:00 minutes away from post-nuclear dinn-dinn.
The critical factors to keep in mind are: kiss is more than fun or a really glam rock band, it is an acronym for a simple way to go about making you into someone you want to look at in the mirror (or just not have to buy new uniforms for), a little fore-thought makes keeping to a training/diet regimen equally simple, and you don't really care what percentage of your calories come from what segment of the dietetic spectrum of foods at this point. What you want are an average of four meals a day consisting of a total of 1600 calories. It's nice to divide them into 4 meals of equal stomach volume if you can, but don't stress over that too much either.
Sugar-free gum and non-peanut nuts are good items to have around for those "gotta have something in my mouth" cravings, but you gotta remember to add them to the daily total when you give in (which you will; welcome to the human race, we're none of us perfect).
Get your head space around the idea that sugary, fizzy drinks are a thing of the past, as are pretty much any type of fast food. Candy is right out, unless you want to add the calories to your daily total. Your call there.
A few small size ice cube trays, a couple three tupperware bottles for drinks, a couple nuke-safe bowls for salads and hot soups. If you can arrange routine access to a 'frig and a microwave oven, this process doesn't have to be uncomfortable or especially expensive to begin. Which is good, because you aren't going to have any of that aboard ship, so you're gonna need the time you have to figure out how to get the same levels of nutrition from your ships galley before you actually have to do that thing.
Actually, once you achieve your initial goals of weight-to-fat ratio, you want to increase your caloric intake as you will then be adding exertion levels to your physical workouts at the same time. If you can get in the regular strength training in addition to the other exercise routines you will have developed, you'll probably be looking at a 2000 calorie average daily intake. That's when you'll want to start paying attention to how many calories are from fat or protein or carbs, etc. In the beginning, not so much, so don't stress yourself.
For the record, my usual daily diet consists of a single bacon and egg Hot Pocket, with two sandwiches for lunch/dinner. All the Crystal Light Iced Tea or Fruit Punch flavor drink I can stand, and a non-sugar sweetener for my coffee called Xylosweet (24.99 plus shipping from Amazon for 5 lbs, made with xylitol which has about a third of the calories of regular sugar, but is used in the same proportions as sugar for cooking or flavoring). When I absolutely will kill someone if faced with one more sandwich, I cheat. Sue me. Actually, I mostly go with a tupperware bowl full of brown rice and some quality steak chopped into bite-seized pieces for easy nuking and chewing.
My exercise routine consists of about 30 minutes a day of either boxing training on the heavy bags (and Bob - you need a precise target to really focus your punching training and Bob's THE go-to guy for that) usually 4 times a week, or roughly the same time on the weight machines at Anytime Fitness with some added time on the treadmill. One or the other, every day. That's the key. Devise a routine you can do, and structure your day around doing it - and staying employed, of course. I find it extremely important that my martial arts interest in historic pugilism and the Backsword (which uses essentially the same foot work) is a critically important contributor to my continued willingness to put in the work. You will have to find your own motivation, but everyone has to so I'm confident you'll have no difficulties there.
I hope you find all this encouraging and helpful in your efforts to achieve greater fitness and general health.