Best way to spend my time?
 

With my job I have mandatory PT every Mon., Wed., and Fri. We spend about a half hour on stretching, pushups, sit-ups, and then what they like to consider a cardio workout. Then we are free to do our own exercise for about an hour. My question is how would this time be best spent considering that it is the only time I have to work out during the week? I'm not looking to get huge, just maybe add a little mass but more important get more definition. Any suggestions or workout plans would be appreciated.

Mass or Definition?
cant do both simultaneously
make your mind up and post

Sure you can.
 

It depends on how flabby you are. You can easily add muscle mass and gain definition at the same time if you got a few pounds to spare. With an hour 3x a week, you should problaby do some circuit training. Gets your muscles working and you end up out of breath at the same time. If you want more muscle then you should instead do a split workout. Focus on a few different muscles groups each day and work them really hard. Like day 1: Chest and tricep. Day 2: Shoulders and back. Day 3: Biceps and legs.

Check this out: Body for Life

This will help point you in the right direction. The workouts are under an hour and provide the right guidance on how to execute the exercises for maximum effectiveness.

There's another side to it that many people fail to consider. All the reps in the world aren't going to provide you a defined look if you don't also address your diet. Healthy nutritional planning is a key part of achieving a well defined look.

Hope this helps.

what equipement do you have available to you?