Interval training is key for torching calories and increasing your speed. Intervals are tough, but they work your body and prepare you well for the races ahead – it is racing season, after all. Even if you don’t like to race, intervals are a great way to add spark to your running routine and help you move past a weight-loss plateau . I wish I could say that I love this workout, but that would be a lie. Just ask my running buddy to tell you how I curse when doing this interval sprint. I can, however, easily admit that I love how I feel afterward, and I love that I burn over 450 calories while doing it. To see the workout, read more. This interval training involves sprinting, so run as fast as you can. But this workout can be a little confusing, so before you start, mentally divide the track into four equal quarters since you will be running 100-yard sprints at different points around

the track. This is not a beginner workout and you should have a strong running/aerobic fitness level before doing this workout. Warmup Four slow laps around the track Dynamic warmup 20 high-knee marching steps 20 booty kicks Skip 20 steps Skip with kick 20 steps 20 heel walks 20 toe walks Intervals Jog 400 yards (one lap at most tracks) Sprint 100 yards Recover* 400 yards Sprint 100 yards Recover 300 yards Sprint 100 yards Recover 200 yards Sprint 100 yards Recover 100 yards Sprint 100 yards Recover 400 to 800 yards Repeat workout one more time! Cooldown Jog two laps Stretch Hamstrings Quads Calves Inner thighs IT band (outer thigh) *You can walk or jog slowly during the recovery period Try the workout and let me know what you think. Running intervals like this has definitely made my steady-paced, longer runs feel dreamy. Source

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Get It Up, Your Heart Rate, That Is: Sprint Intervals at the Track