| Increasing intensity in this manner will definitely help your burn more calories during your workout. Now, definitely does cause stress to the joints. If you are concerned about this then try a similar intensity on the gym elliptical. This machine is much more friendly to the joints than the treadmill or track.
It is important to remember, that a particular heart rate at a given duration will burn the same amount of calories on either the track, treadmill, elliptical or even a stationary bike. It all depends on what type of exercise you are most comfortable with.
Safety and injury prevention should always be your primary concerns. | 
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