You can also try one of those high intensity interval training (HIIT) workouts. There are cardio ones and weight lifting ones... the personal trainer that I had taught me this neat workout that was simple but had me sore for an entire week. It also only took like 40 minutes to complete, so I find HIIT type of workouts are the best for people who can't spare more than an hour per day at the gym.
The workout goes like this:
1) You start with 21 reps of high kettlebell swing (i.e. high as in you raise it over your head). Once you've finished the kettlebell swings, do 21 pushups without taking a break, then 21 squats with the same kettlebell. Take a short break (three minutes at most?)
2) For the second interval, do 18 reps of all three exercises from above while taking no or as short break as possible in between. Make sure to take a 3-minute break for each interval. With each succession, you are reducing the number of reps for each exercise by 3.
e.g. 1st interval: 21 reps for each exercise
3rd interval: 15 reps for each exercise
6th interval: 6 reps for each exercise
7th (last) interval: 3 reps for each exercise
Make sure to eat and rest sufficient amount after this workout. I did this while on a diet, and it took me ages to recover.