Let's face it: The majority of the day is spent chained to your desk. Burning the midnight oil can make hitting the gym impossible, especially in these days of the BlackBerry, when getting away from work is harder than ever.

So why not make the office work for you? Los Angeles-based personal fitness trainer Jamie Murphy offers the following exercises that can easily be done at the office—and will add to your daily calorie burn. This routine is great for those days when work has no end in sight. Or better yet, think of it as bonus on top of your regular workout.

1. Stop circling the parking lot for the closest space! Pull into a farther-away spot and enjoy the extra walk. Remember, every bit of exercise counts.

2. Ignore the elevator and march up and down the stairs. Your glutes will thank you! If you work on the 33rd floor, walk up the first few flights and then hit the Up button for the remaining climb. Push yourself by adding another flight each day or week, depending on your stamina.

3. Trade your chair for a stability ball. Sure, it looks funny, but it's an amazing core workout. Start with 30 minutes a day and work up to the entire day.

4. Be conscious of your body. Sit with good posture at your desk, and every now and then, take a few deep breaths to engage the abdominal area. If every half-hour you let out four deep, contracting breaths, it's like adding 500 crunches a week.

5. Do the following twice a day:
Inclined Push-Ups: Place palms on desk and angle feet out, so your body is in a plank position. Do as many push-ups as you can in 60 seconds.
Ab Rolls: Facing the chair, place hands on the seat of a wheeled chair and knees on the ground. Push the chair away and pull back in. Repeat as many times as you can in 60 seconds.
Reverse Push-Ups: Facing away from desk, place palms behind you, then lower and raise as many times as you can in 60 seconds.

6. While at your computer, twist your chair 45 degrees to either side and keep your chest square with the screen. This movement is excellent for toning the obliques. Add deep breaths for greater benefits.

7. Slightly lift your bum off your seat and press palms onto your desk. Don't hunch over—keep posture upright.

8. Get up and stretch. Reach high above your head, spread your legs and bend at the waist and reach your palms for the floor. Do yoga poses like downward dog, wheel or handstands against the wall. (Just remember to kick off your shoes first.)

9. Turn a conference call into a "booty call." Instead of sitting through those never-ending conversations, push the chair away and stand. Add a set of deep squats. If you're in listening mode, hit the speaker phone and do a round of jumping jacks or jog in place.

10. Take a break and walk to Starbucks for an iced green tea without  added sugar.