Working out for shorter but more intense periods of time has the advantage of saving you time and making your body accustomed to greater levels of physical stress. On the other hand, it also makes you more likely to injure yourself. If you only work out for a short period of time and limit the intensity too much, you might just be wasting your time entirely. The effectiveness of these short programs will depend very much on individual physiology, so you should always be aware of the signals that your own body is sending you.

It can be effective to conduct only light daily workouts if you also limit your food intake significantly. If you find yourself getting sluggish during workouts, that could indicate that you aren't getting enough calories to support your activity level. This also means that your metabolism is likely not working as hard as it can, limiting your overall tempo of weight loss. You should feel invigorated and energetic every time you work out, and you should not feel serious amounts of pain.

If you find yourself hurting more with every workout, then you are either making a mistake with your form or working out too hard for your body to support. Although you can see very rapid results by working out fiercely over a short period of time, in the long run an injury can completely derail an exercise program. Remaining in good health should be your priority. You should try to increase the intensity of your workout gradually over a long period of time, waiting for your body to get accustomed to the new level of activity at each stage.