For each workout session, start with whichever activity (cardio or strength) that you want to maximize - the second activity will be always be compromised due to fatigue.

Bored of your regular cardio routine? Try wearing ankle or wrist weights while doing your cario - you'll increase your resistance, burn more calories and challenge your muscles to work harder.

To increase intensity and add variety to your workout, try training opposite muscle groups, such as your biceps & triceps and quads & hamstrings, back-to-back (known as supersetting).