PT = Physical Training:

I've never lifted weights but i'm really into calisthenics and 
body-weight exercises.  Obviously there is no substitute to running 
and/or swimming.

Running    : Runner's World
Swimming   : Training

Here's what i do do, aside from swim and run:

Drink Water!

Never exercise without hydrating before and during the workout. Pull ups: usually a pyramid of reps going up and coming down. I use five different holds on the bar to isolate muscle groups: 1. shoulder width, palms away 2. hands together, palms inward 3. hands together, palms away 4. wide grip, behind-the-neck 5. in-line, both sides (commando) Push ups: either a pyramid of reps with different stances or an endurance set using the first three stances: 1. under the shoulders, elbows in 2. diamond, or close grip 3. wide grip, elbows at 90 4. dive-bombers Abs: this series is to be done with the same number of reps in each exercise, with little rest, and attention to form for max benefit. 1. regular sit ups, nose between knees 2. half sit ups, eyes on the ceiling 3. crunches, legs crossed and verticle 4. tear drops (lay flat, hands over head, lift legs to verticle and meet with hands, recover but do not let feet touch the deck.) 5. side sit ups (cross arms on chest, alternating shoulders between knees.) 6. side crunches (knees on ground to one side, then the other, finger tips behind ears, do not pull your head up with your hands, let your abs do it.) 7. leg raises (hands supporting lower back, point toes, knees slightly bent, lift hips off deck when legs are verticle, recover but do not let ankles touch the deck.) 8. flutter kicks, 4 count 9. wide cross-overs, 4 count (ankles six inches off the deck, open legs and close them by crossing one ankle under the other, repeat but cross other ankle underneath to close = 1 rep.) 10. cross-over lifts, 4 count (open legs, close legs, lift legs, recover = 1 rep, ankles 6 inches off the deck.) 11. reverse crunches, knees to chest Calisthenics: there are countless types of aerobic calisthenics, I found 15 I like to do and use 15 minutes to do them. 45 seconds of first exercise, 15 seconds rest, 45 seconds next exercise, 15 seconds rest, etc. I recommend squat jumps, body builders, v bikes, v sits, mountain climbers, wall sit, push ups, quad burners, jump lunges, triangle push-ups, crunches, etc... find some you like. Again,

Drink Water!