The festive party season is looming and the abundance of food and drink consumed over the next few weeks will inevitably lead to weight gain. Some of us will surrender and accept the extra kilos as part of the equation, telling ourselves we can drop them in the new year when life is less busy. But the best thing to do is not give up, just become more efficient. It's not always necessary to do the recommended 30-45 minutes of continuous walking, running or cycling at a moderate pace to keep the fat cells from expanding. Even if you only have 30 minutes or less, it is possible to get some benefit. Intensity is the key to keeping fit when you're short of time. If you normally squeeze in 40 minutes on a piece of cardio equipment, but only have 20 minutes, just increase the speed or resistance. You don't have to go twice as hard, just push yourself a bit harder and you'll improve your aerobic capacity as well as burn those extra calories. There are two ways to go about this. The first is a steady state workout. To do this, increase one or more of the variables on the piece of cardio equipment. Then keep up this new harder pace for the entire workout, apart from a few minutes warm up and cool down (even more important if you're upping the intensity). The second type is called intervals in which you alternate between really easy and really difficult. By allowing yourself a good recovery, you can push the intensity that much harder for a short period of time. The same holds true for outside activities such as running, swimming, cycling and even walking. On the right are two examples of 20-minute workouts to maintain your fitness level. If possible, it's best to complete at least two of these intense workouts a week but no more than three. Remember, the intensity is hard but the time is short. Both these workouts will keep the excesses of the season at bay and may increase your fitness level. However, these programmes aren't for everyone. Only those who have done cardio workouts for at least three months, or who can handle at least 30 minutes of continuous aerobic exercise at a moderate intensity, should attempt them. If you're new to exercise or haven't exercised for more than three months, check with your doctor as well as a fitness professional before you begin. By working through the festive season, you could steal a march on the inevitable New Year's resolutions. Workout 1 Treadmill steady state: warm up for three minutes, starting at a walking pace and increasing to a slow jog with no incline. Then either raise the incline or increase the speed until you are breathing hard but don't feel like you're dying. Hold this for 15 minutes. Cool down by slowing and lowering the incline if raised. Jog or walk for at least two minutes. Workout 2 Treadmill Intervals: warm up for three minutes with no incline, walking at first then slowly increasing to a jog. Increase the incline or speed until you're almost out of breath. Hold this pace for one minute. Slow down to a jog with no incline for one minute. Repeat this sequence of hard and slow six more times. Then cool down by decreasing the incline and jogging slowly for two minutes.