You can get dang strong and gain high endurance doing strictly body weight exercises. I've been a Marine grunt coming up on 6 years now and the best workouts are the ones outside the gym in my experience. Weight lifting is great for putting on mass and certain directional muscle strength but in all actuality functional strength (i.e. stuff that's applicable to daily life and/or any unfortunate situation you might find yourself in) is the best kind of fitness. Stuff like crossfit and P90x are good regimens that you can follow but even then it's overkill IMO.
Here's a quick little down and dirty routine you might try following...
-3 mile run daily (if you can't run 3 miles at a consistent pace non-stop start with a mile and work your way up to it. keeping a consistent pace and having good running form is the most important part of the run). It's a great thing to do in the mornings before your day starts; wakes you up and gets blood flowing nicely. Has cardio, fat burning, toning, and muscle endurance benefits. Marine Corps PFT standard for a "perfect" run time is 3 miles in 18 minutes. Not that you have to do that but it's a good goal.
Upper Body:
-Pushups: 5 sets of 20 repetitions. Do them slowly, keep your back straight, head up, core flexed, go all the way down to 90 degrees at the elbows, and explode up. You can vary the muscles isolated by putting your hands closer and farther apart. Diamond pushups isolate triceps nicely and nail inner chest.
-Pullups: 5 sets of 5 repetitions. Pullups are the ultimate expression of upper body strength IMO. Works back, triceps, and core. Pullups are done with your palms facing AWAY from you. If your palms are facing you then you're doing a chinup and working more bicep muscle. That being said you can mix up the grips to focus on different muscle groups. Also, changing the width of your grip on the bar will work different muscles too.
-Dive Bomber Pushups: 5 sets of 10 repetitions. Best thing to do is YouTube them and see how they're done. They suck.
Core...without a strong core you're limiting your potential and increasing your likelyhood of injury doing strenuous activities...CORE CORE CORE:
-Crunches: 5 sets of 30 repetitions. Anchor your toes under something heavy and rock solid. Get your butt as close to your heels as you can, fold your arms across your chest gripping your biceps and using your abdominals, lift your body up until your elbows touch your thighs. Up and down motions should be deliberate and controlled to avoid back stress
-Flutter kicks: 5 sets of 15 4-count repetitions. This is one of my favorites. It not only hits your core but your legs and ass as well. Lie flat on the floor, hands under your butt. Lift your legs off the ground 6 inches and kick in a slow, controlled motion. Once you complete your count, hold at 6 inches for a few seconds and then relax. Crunch your core and lift your head up off the ground while you're doing them.
-Planks: hold position until muscle failiure. Its simple, get in the pushup position resting on your elbows. hold your back straight, flex your core, and hold it...it burns. Do this a few times. If you want a challenge, time yourself and try to stay consistent and improve each time.
Legs:
-Air squats: 5 sets of 20 repetitions. These are simple and effective. Form is key, if you don't know proper form YouTube it and learn or else you'll just hurt yourself eventually...Feet about shoulder width apart, squat down slowly keeping your back straight and upright. up and down motions should be controlled and fluid.
-Lunges: 5 sets of 20 repetitions (10 per leg). Another one to YouTube to learn proper form. As with squats, keep your back straight and core flexed.
-Box Jumps: 5 sets of 10 repetitions. This works explosive strength, reflexes, and endurance. find something stable thats at least 12" high and jump up onto it, and then back down. You should only have a 1 or 2 second pause inbetween jumps. If you're a little shaky about this one YouTube it for demonstrations. It'll also work cardio.
Cardio:
-Side Straddle Hops (jumping jacks): 5 sets of 30: If you don't know how to do these, you didn't have a childhood lol! Works cardio, endurance, and calf strength. Make sure to swing your arms all the way!
-Shuttle run (wind sprints): find a 100 meter stretch of road or grass that's flat and free of obstructions. Sprint to one side, turn around and sprint back. If your cardio isn't that great start with a 50 meter distance. Do a total of 1000 meters (if you're using the 100m distance) or 500 meters if using the 50m distance.
-8-count body builders: 5 sets of 10. YouTube this for a proper demonstration. Form is the most important thing here!!! don't worry about doing them fast until your form is good. This is a total body slay. >
I hope this is a good starting point for you. There's a bajillion other exercises I could put down here but these are some basic ones that will give you a good foundation and begin to shape warrior fitness in you. If something is too difficult to do in entirety just crank it down a tad. As you improve you can increase the number of sets and repetitions and the speed at which you do all of it. I recommend that you do this every other day until you're in good condition, then do it every day. If you want additional exercises and more info please feel free to PM me anytime.
Oh and get on a good diet plan too. Nothing crazy just eat healthy and limit carbonated drink, fatty fast food, and sweet shit intake. Nutrition is just as important as exercises if not more important!
Kill Bodies,
Josh